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Preimplantation genetic diagnosis (PGD): European perspectives and the German situation.
This article gives an overview about the ethical dispute on preimplantation genetic diagnosis (PGD), its legal status and its practical usage in Europe. We provide a detailed description of the situation in Germany wherein prenatal diagnosis is routinely applied, but PGD is prohibited on the basis of the internationally unique embryo protection act (EPA) that was put into force in 1991. Both PGD and stem cell research were vigorously debated in Germany during the last four years. As regards the PGD debate specifically, the voices of the ones directly affected were not adequately taken into consideration. We describe the predominant lines of argumentation in this debate and some essential results of our "bioethical field study" of opinions on and usage of PGD in Germany and their implications for the German legislation and ethical theory. PMID:15545119
Krones, Tanja; Richter, Gerd
[Ethical aspects of preimplantation genetic diagnosis (PGD)].
The controversy surrounding PGD has not abated in recent times. This is especially the case for PGD-based tissue typing, which is used to select a future child who could serve as a stem cell donor for an older sick sibling. We examine three types of ethical argument cited against PGD in general, and specifically against tissue-typing PGD. These arguments focus on the moral status of the early embryo, the eugenics issue, and the charge that the future child is being exploited. We conclude that none of these three arguments is unassailable, and that it is the reproductive freedom of couples considering PGD that should prevail. PMID:22375368
Mauron, Alex
PGD patients' and providers' attitudes to the use and regulation of preimplantation genetic diagnosis
Microsoft Academic Search
Preimplantation genetic diagnosis (PGD) providers and patients have a vested interest in policy related to the use and regulation of PGD. To understand their experiences and attitudes, 32 in-depth interviews were conducted. Participants included 13 people at risk of transmitting a single-gene alteration to their children (10\\/13 had actually used PGD to try to have an unaffected child) and 19
Andrea L Kalfoglou; Joan Scott; Kathy Hudson
On the relation between moral, legal and evaluative justifications of pre-implantation genetic diagnosis (PGD).
In Germany the question whether to uphold or repeal the judicial prohibition on Pre-implantation Genetic Diagnosis (PGD) is being debated from quite different standpoints. This paper differentiates the major arguments according to their reasons as a) moral, b) evaluative (i.e. cultural/religious), and c) legal. The arguments for and against PGD can be divided by content into three groups: arguments relating to the status of the embryo, focusing on individual actions in the implementation of PGD, and relating to the foreseeable or probable consequences of PGD. In Germany, from a legal perspective, the status of the embryo does not permit the intervention of PGD; from a purely moral perspective, a prohibition on PGD does not appear defensible. It remains an open question, however, whether the moral argument permitting PGD should be restricted for evaluative (cultural) reasons. The paper discusses the species-ethical reasons, for which Jurgen Habermas sees worrisome consequences in the wake of PGD to the extent that we comprehend it as the forerunner of a 'positive eugenics'. It would so disrupt the natural preconditions of our universal morality. The question of whether to prohibit or allow PGD is not merely a question of simple moral and/or legal arguments, but demands a choice between evaluative, moral and (still to be specified) species-ethical arguments, and the question remains open. PMID:16206459
Lohmann, Georg
Preimplantation genetic diagnosis (PGD) influences adrenal development and response to cold stress in resulting mice.
Preimplantation genetic diagnosis (PGD) has gained widespread application in clinical medicine and hence the health of PGD offspring needs to be systematically assessed. Given the critical role of the stress response in growth and health, assessments of the development and function of the stress system might help to clarify the health outcomes of PGD. In this study, we constructed a PGD-conceived mouse model and used naturally conceived mice as controls; we used this model to evaluate the potential effect of PGD procedures on the stress system of the offspring. Serum and tissues of stress organs, namely the hypothalamus, locus coeruleus and adrenal gland, were collected from 5-week-old mice in the basal state or after cold stress. The serum levels of stress-related hormones and the structural and functional indices of the stress organs were then examined. In the basal state, ultrastructural abnormalities and low expression of genes involved in steroid hormone synthesis were found in the adrenals of the PGD mice, which had low corticosterone and high epinephrine levels compared with those of control mice. After acute cold stress, the PGD mice continued to show structural and glucocorticoid secretion abnormalities resulting in a late response to the environmental change. Thus, our study indicates that PGD manipulations affect adrenal development, result in structural and functional abnormalities of the adrenals in the offspring and influence their reactivity and adaptability to cold stress. PMID:24104561
Zeng, Yan; Lv, Zhuo; Gu, Leilei; Wang, Liu; Zhou, Zuomin; Zhu, Hui; Zhou, Qi; Sha, Jiahao
Public, expert and patients' opinions on preimplantation genetic diagnosis (PGD) in Germany
The regulation of reproductive medicine technologies differs significantly among Western industrialized countries. In Germany, preimplantation genetic diagnosis (PGD) is prohibited due to the Embryo Protection Act, which came into force in 1991. In the last 5 years, this prohibition has been vigorously debated. In the present studies, which are part of the German research programme on ethical implications of the
Tanja Krones; Elmar Schl�ter; Konstantin Manolopoulos; Karin Bock; Hans-Rudolf Tinneberg; Manuela C Koch; Martin Lindner; Georg F Hoffmann; Ertan Mayatepek; Gerd Huels; Elke Neuwohner; Susan El Ansari; Thomas Wissner; Gerd Richter
Preimplantation Genetic Diagnosis (PGD) for Genetic Prion Disorder Due to F198S Mutation in the PRNP Gene.
IMPORTANCE To describe the first case of preimplantation genetic diagnosis (PGD) and in vitro fertilization (IVF) performed for the prevention of genetic prion disease in the children of a 27-year-old asymptomatic woman with a family history of Gerstmann-Str�ussler-Sheinker syndrome (GSS). OBSERVATIONS PGD and fertilization cycles resulted in detection of 6 F198S mutation-free embryos. Of these, 2 were selected for embryo transfer to the patient's uterus, yielding a clinical twin pregnancy and birth of healthy but slightly premature offspring with normal development at age 27 months. CONCLUSION AND RELEVANCE IVF with PGD is a viable option for couples who wish to avoid passing the disease to their offspring. Neurologists should be aware of PGD to be able to better consult at-risk families on their reproductive choices. PMID:24493558
Uflacker, Alice; Doraiswamy, P Murali; Rechitsky, Svetlana; See, Tricia; Geschwind, Michael; Tur-Kaspa, Ilan
Evaluation of PCR-based preimplantation genetic diagnosis applied to monogenic diseases: a collaborative ESHRE PGD consortium study.
Preimplantation genetic diagnosis (PGD) for monogenic disorders currently involves polymerase chain reaction (PCR)-based methods, which must be robust, sensitive and highly accurate, precluding misdiagnosis. Twelve adverse misdiagnoses reported to the ESHRE PGD-Consortium are likely an underestimate. This retrospective study, involving six PGD centres, assessed the validity of PCR-based PGD through reanalysis of untransferred embryos from monogenic-PGD cycles. Data were collected on the genotype concordance at PGD and follow-up from 940 untransferred embryos, including details on the parameters of PGD cycles: category of monogenic disease, embryo morphology, embryo biopsy and genotype assay strategy. To determine the validity of PCR-based PGD, the sensitivity (Se), specificity (Sp) and diagnostic accuracy were calculated. Stratified analyses were also conducted to assess the influence of the parameters above on the validity of PCR-based PGD. The analysis of overall data showed that 93.7% of embryos had been correctly classified at the time of PGD, with Se of 99.2% and Sp of 80.9%. The stratified analyses found that diagnostic accuracy is statistically significantly higher when PGD is performed on two cells versus one cell (P=0.001). Se was significantly higher when multiplex protocols versus singleplex protocols were applied (P=0.005), as well as for PGD applied on cells from good compared with poor morphology embryos (P=0.032). Morphology, however, did not affect diagnostic accuracy. Multiplex PCR-based methods on one cell, are as robust as those on two cells regarding false negative rate, which is the most important criteria for clinical PGD applications. Overall, this study demonstrates the validity, robustness and high diagnostic value of PCR-based PGD. PMID:24301057
Dreesen, Jos; Destouni, Aspasia; Kourlaba, Georgia; Degn, Birte; Mette, Wulf Christensen; Carvalho, Filipa; Moutou, Celine; Sengupta, Sioban; Dhanjal, Seema; Renwick, Pamela; Davies, Steven; Kanavakis, Emmanouel; Harton, Gary; Traeger-Synodinos, Joanne
Preimplantation genetic diagnosis (PGD) in Europe: diversity of legislation a challenge to the community and its citizens.
Preimplantation genetic diagnosis (PGD) aims to safeguard the reproductive confidence of couples who have an increased risk of having a child with a serious hereditary disease. Non-directive genetic counselling is an essential part of PGD. Lately, performance of PGD for some new and non-medical indications, such as selecting for a tissue-matching embryo for a saviour sibling, or sex-selection for family-balancing, has raised ethical concerns. Who decides when to perform PGD, and for which conditions? The European member states have very diverse regulation on PGD. Some countries totally ban PGD, while the others keep close track of the new applications. The people in need of PGD seek it in the other member states. These cross-border treatments cause psychological stress and pose many so far unresolved legal questions. The individuals need more information about all the aspects of PGD. This article analyses contemporary indications for PGD in Europe and relevant ethical discussion, and second, shows the diversity in regulation and reflects the consequences thereof. PMID:17639853
Soini, S
[Preimplantation diagnosis--PID: preimplantation genetic diagnosis (PGD) and preimplantation genetic screening (PGS)].
Preimplantation diagnosis (PID) comprises all the relevant diagnostic procedures for the investigation of genetic, structural, or numerical changes of the genetic information in spermatozoa and oocytes as well as in embryos after in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). PID of oocytes is well established in Germany for the above-mentioned indications. PID at the embryonic level, i.e., trophectoderm biopsy of blastocysts, is possible in centers with proven expertise in reproductive medicine and human genetics. A high risk for genetic disease in the child or a high likelihood for stillbirth or miscarriage is a prerequisite for PID. A specialized ethics committee is required to look into each case before making a decision. While PID is still under development in Germany, it has been a well-established technology worldwide for 24 years. International experience in PID and the resulting implications are discussed in this article. PMID:24337129
Montag, M; Toth, B; Strowitzki, T
Preimplantation genetic diagnosis (PGD) for nonsyndromic deafness by polar body and blastomere biopsy
Purpose��Development of an efficient and reliable PGD protocol for nonsyndromic deafness, by polar body (PB) and blastomere PGD.\\u000a \\u000a \\u000a \\u000a Methods��The GJB2\\/GJB6 mutations along with 12 polymorphic markers were used in PGD analysis of blastomeres or polar bodies in 14 couples\\u000a for 35 cycles. Marker informativity, diagnosis rates, Allele Drop Out (ADO) rates and PB1 heterozygosity rates were assessed.\\u000a \\u000a \\u000a \\u000a Results��Six cycles were
Gheona Altarescu; Talia Eldar-Geva; Baruch Brooks; Edith Zylber-Haran; Irit Varshaver; Ehud J. Margalioth; Ephrat Levy-Lahad; Paul Renbaum
Prenatal diagnosis and preimplantation genetic diagnosis: novel technologies and state of the art of PGD in different regions of the world.
Prenatal diagnosis (PND) aims to provide accurate, rapid results as early in pregnancy as possible. Conventional PND involves sampling cells of foetal origin by chorionic villus sampling at 11-14th weeks of pregnancy or amniocentesis after 15th week. These are invasive procedures and have a small but significant rate of 0.5% to 1% for loss of pregnancy. An alternative to existing methods for conventional PND for couples at risk of transmitting a genetic disease to their child is preimplantation genetic diagnosis (PGD). PGD is a newly emerging form of a very early prenatal diagnosis. The technique combines assisted reproductive technology with molecular genetics and cytogenetics to allow the identification of abnormality in embryos prior to implantation. The diagnosis of genetic disease in human preimplantation embryos was pioneered in the late 1980s for testing of aneuploidy, single gene and X-linked disease, such as cystic fibrosis, haemophilia and chromosomal abnormalities. The PGD-related legal and ethical issues have been debated at many levels both nationally and internationally. The attitude towards PGD varies substantially not only in different parts of the world but also within the Europe, owing to scientific, cultural and religious differences. PGD has become widely practised throughout the world for various indications and can substantially decrease the eventual risks of passing a genetic undesired condition of the offspring. Nevertheless, its extension to some new and non-medical indications has raised ethical concerns, in particular its potential eugenic dimension. PMID:21692923
Peyvandi, F; Garagiola, I; Mortarino, M
Benefits and drawbacks of preimplantation genetic diagnosis (PGD) for reciprocal translocations: lessons from a prospective cohort study.
Preimplantation genetic diagnosis (PGD) using fluorescence in situ hybridisation probes was carried out for 59 couples carrying reciprocal translocations. Before treatment, 85% of pregnancies had resulted in spontaneous miscarriage and five couples had achieved a healthy live-birth delivery. Following treatment, 33% of pregnancies failed and 21 of 59 couples had a healthy live-born child. The accuracy of diagnosis was 92% (8% false abnormal and 0% false normal results). The overall incidence of 2:2 alternate segregation products was 44%; however, products consistent with 2:2 adjacent segregation were ~twice as likely from male heterozygotes, and those with 3:1 disjunction were three times more likely from female heterozygotes. Our results indicate that up to three stimulation cycles per couple would give an ~50% chance of a successful live birth, with the risk of miscarriage reduced to the level found in the general population. In our study, 87% of all normal/balanced embryos available were identified as being suitable for transfer. We conclude that PGD provides benefit for couples with high-risk translocations by reducing the risk of miscarriage and avoiding a pregnancy with an unbalanced form of the translocation; however, for fertile carriers of translocations with a low risk of conceiving a chromosomally unbalanced offspring, natural conception may be a more viable option. PMID:23386032
Scriven, Paul N; Flinter, Frances A; Khalaf, Yakoub; Lashwood, Alison; Mackie Ogilvie, Caroline
Addressing the idiosyncratic needs of Orthodox Jewish couples requesting sex selection by preimplantation genetic diagnosis (PGD).
We report here on ethical considerations addressing the idiosyncratic needs of two Orthodox Jewish couples requesting sex selection through PGD. The patients' considerations stem from generally healthy concerns, are not based on any gender biases and have little chance of having any major societal impact, given the idiosyncratic nature of the situation. Halakhah, the legal and ethical system of rabbinic Orthodox Judaism, generally opposes sex selection through PGD for nonmedical reasons, but would approve the procedure in these cases. Meeting these needs within the context of the doctor-patient relationship necessitates reconsidering to some extent the ASRM Ethics Committee guidelines. PMID:17136601
Grazi, Richard V; Wolowelsky, Joel B
Accuracy of preimplantation genetic diagnosis (PGD) of single gene and chromosomal disorders
We have developed a polar body inferred approach for preconception diagnosis of single gene and chromosomal disorders. Preconception PCR or FISH analysis was performed in a total of 310 first polar bodies for the following genetic conditions: cystic fibrosis, hemophilia A, alpha-1-antitrypsin deficiency, Tay Sachs disease, retinitis pigmentosa and common chromosomal trisomies. An important advantage of this approach is the
Y. Verlinsky; C. Strom; S. Rechitsky
Addressing the idiosyncratic needs of Orthodox Jewish couples requesting sex selection by preimplantation genetic diagnosis (PGD)
We report here on ethical considerations addressing the idiosyncratic needs of two Orthodox Jewish couples requesting sex\\u000a selection through PGD. The patients� considerations stem from generally healthy concerns, are not based on any gender biases\\u000a and have little chance of having any major societal impact, given the idiosyncratic nature of the situation. Halakhah, the\\u000a legal and ethical system of rabbinic
Richard V. Grazi; Joel B. Wolowelsky
Is Intracytoplasmic Sperm Injection Itself an Indication to Perform Preimplantation Genetic Diagnosis (PGD)?
Intracytoplasmic sperm injection (ICSI) provides the only sufficient treatment to overcome severe forms of male infertility. However, male infertility is linked to several genetic problems as an increased number of chromosomal aberrations, cystic fibrosis transmembrane conductance regulator gene mutations, Y-chromosome microdeletions, and androgen receptor mutations. Therefore, these couples are at a higher risk of transmitting genetic problems to their offspring
M. Ludwig; A. Geipel; C. Berg; U. Gembruch; E. Schwinger; K. Diedrich
PGD patients' and providers' attitudes to the use and regulation of preimplantation genetic
Preimplantation genetic diagnosis and �savior siblings�
From its emergence, preimplantation genetic diagnosis (PGD) has been opposed by religious, feminist, and disability-rights advocates. PGD has developed, however, to extend beyond genetic diagnosis of embryos to diagnose chromosomal abnormalities. Evidence shows that PGD is safe, children born after in vitro fertilization (IVF) and PGD having no higher rate of birth defects than children of normal pregnancies. Laws may
B. M. Dickens
Pre-implantation genetic diagnosis
Pre-implantation genetic diagnosis (PGD) was developed in the UK over 10 years ago. There are now more than 40 centres worldwide carrying out PGD and 150 babies have been born after genetic testing on day 3 of development, at the cleavage stage. This review covers the current status of PGD, the technology used and the types of genetically determined diseases
Joy D. A. Delhanty; Joyce C. Harper
[The physician's role in various clinical contexts. Physician counseling on in vitro fertilization (IVF) and preimplantation genetic diagnosis (PGD)].
The role of the physician in the context of in vitro fertilization and preimplantation genetic diagnosis has certain distinct characteristics. Involuntary childlessness by definition of the WHO is a disease with good treatment options. As it is not considered a medical emergency, the focus lies more on intensive information giving, education, and counseling. Because the diagnosis and treatment can be a medical and psychological strain for the couple, counseling should address both medical and psychological aspects. The physician needs to have detailed medical knowledge as well as good communication skills to be able to meet the specific needs of the couple. Moreover, the physician should point out the realistic success rates of treatment and should refer to alternatives, such as remaining childless, adoption, and sperm or egg donation. The concurrent inclusion of biological, psychological, social, and ethical aspects in terms of psychosomatic basic care (Psychosomatische Grundversorgung) seems to be useful. There is potential for conflicts, for example, due to the economic interests of the physician. On the other hand, the treatment can be a financial burden for the couple. Of importance are the physician's and the patient's moral concepts, especially concerning some aspects of therapy (sperm and egg donation, surrogacy). The expected welfare of the intended child should also be respected (e.g., higher risk of preterm birth in multiple pregnancies). Further possible conflicts in reproductive medicine arise because of the crossing of moral boundaries (oocyte donation for postmenopausal women, surrogacy, cloning of human beings). The framework of counseling is based on the guidelines of the German Medical Association (Bundes�rztekammer) for assisted reproduction (2006). Preimplantation genetic diagnosis has special requirements from a medical and psychosocial point of view. PMID:22936482
Kentenich, H; Tandler-Schneider, A
Preimplantation genetic diagnosis.
Preimplantation genetic diagnosis (PGD) is the screening of embryos at the cleavage stage in order to select and transfer only the desired embryo. The main indications of PGD are monogenic disorders and aneuploidy. This article reviews the recent advances in PGD methodology and presents their advantages, disadvantages and challenges. Ethical considerations arising with more widespread use of PGD for physical traits is also discussed. PGD for monogenic disorders remains the most successful indication, but is technically more challenging. PGS for aneuploidy has passed through a period of reconsideration and is now re-emerging with complete genome screening. PMID:20595946
Lalioti, M D
Preimplantation Genetic Diagnosis
Preimplantation genetic diagnosis (PGD) can provide genetic information on embryos obtained through in vitro fertilization (IVF), allowing implantation of embryos identified as unaffected with a given genetic or chromosomal disorder. With the availability of increasingly sophisticated genetic testing, its use has advanced from the selection of female embryos for the prevention of X-linked genetic diseases to testing for single gene
Lora K. Shahine; Aaron B. Caughey
Social welfare, genetic welfare? Boundary-work in the IVF\\/PGD clinic
Through the lens of the �welfare of the child� assessment, this paper explores how staff working in the area of in vitro fertilisation and preimplantation genetic diagnosis (IVF\\/PGD) balance reflexive relations of legitimacy and accountability between the public and private spheres, and between medicine, the citizen and the state. The wider research of which this analysis is a part uses
Kathryn Ehrich; Clare Williams; Rosamund Scott; Jane Sandall; Bobbie Farsides
Ethics of preimplantation genetic diagnosis
This paper briefly reviews the current status of preimplantation genetic diagnosis (PGD), to offer a basis for discussion about its ethical background. It describes the situation regarding modern types of PGD, which involve analyses on the inheritance by human embryos of chromosomal disorders or gene mutations. The current scale of these treatments is discussed, together with the progress of new
Yury Verlinsky
PGD for cystic fibrosis patients and couples at risk of an additional genetic disorder combined with 24-chromosome aneuploidy testing.
Preimplantation genetic diagnosis (PGD) for inherited disorders is presently applied for more than 300 different conditions. The most frequent PGD indication is cystic fibrosis (CF), the largest series of which is reviewed here, totalling 404 PGD cycles. This involved testing for 52 different CFTR mutations with almost half of the cases (195/404 cycles) performed for ?F508 mutation, one-quarter (103/404 cycles) for six other frequent mutations and only a few for the remaining 45 CFTR mutations. There were 44 PGD cycles performed for 25 CF-affected homozygous or double-heterozygous CF patients (18 male and seven female partners), which involved testing simultaneously for three mutations, resulting in birth of 13 healthy CF-free children and no misdiagnosis. PGD was also performed for six couples at a combined risk of producing offspring with CF and another genetic disorder. Concomitant testing for CFTR and other mutations resulted in birth of six healthy children, free of both CF and another genetic disorder in all but one cycle. A total of 96 PGD cycles for CF were performed with simultaneous aneuploidy testing, including microarray-based 24-chromosome analysis, as a comprehensive PGD for two or more conditions in the same biopsy material. PMID:23523379
Rechitsky, Svetlana; Verlinsky, Oleg; Kuliev, Anver
Preimplantation Genetic Diagnosis of Inherited Cancer: Familial Adenomatous Polyposis Coli
Purpose:Our purpose was to achieve preimplantation genetic diagnosis (PGD) of the dominant cancer predisposition syndrome, familial adenomatous polyposis coli (FAPC), as an alternative to prenatal diagnosis.
Asangla Ao; Dagan Wells; Alan H. Handyside; Robert M. L. Winston; Joy D. A. Delhanty
Reprogenetics: Preimplantational genetics diagnosis.
Preimplantational Genetics Diagnosis (PGD) is requested by geneticists and reproductive specialists. Usually geneticists ask for PGD because one or both members of the couple have an increased genetic risk for having an affected offspring. On the other hand, reproductive specialists ask for embryo aneuploidy screening (PGS) to assures an euploid embryo transfer, with the purpose to achieve an ongoing pregnancy, although the couple have normal karyotypes. As embryonic aneuploidies are responsible for pre and post implantation abortions, it is logical to considerer that the screening of the embryonic aneuploidies prior to embryo transfer could improve the efficiency of the in vitro fertilization procedures. Nevertheless, it is still premature to affirm this until well-designed clinical trials were done, especially in women of advanced age where the rate of embryos with aneuploidies is much greater. Although the indications of PGD are similar to conventional prenatal diagnosis (PND), PGD has less ethical objections than the PND. As with the PGD/PGS results only unaffected embryos are transferred, both methods can avoid the decision to interrupt the pregnancy due to a genetic problem; this makes an important difference when compared to conventional prenatal diagnosis. PMID:24764761
Coco, Roberto
Pre-implantation genetic diagnosis (PGD) is generally defined as the testing of pre-implantation stage embryos or oocytes for genetic defects. It has been developed for couples whose potential offspring are at risk of severe Mendelian disorders, structural chromosome abnormalities or mitochondrial disorders. Pre-implantation embryo diagnosis requires in vitro fertilization, embryo biopsy and either using fluorescent in situ hybridization or polymerase chain reaction at the single cell level. Therefore, it is a complex procedure which requires much experience. Aneuploidy screening to improve medically assisted reproduction (in vitro fertilization/intracytoplasmic sperm injection) is a variant type of PGD. The past, present and future of this development are strongly related to the natural occurrence of chromosomal mosaicism in the pre-implantation embryo. PGD should be included in each reproductive health care programme. It is recognized as an important alternative to pre-natal diagnosis. However, diagnosis from a single cell remains a technically challenging procedure, and the risk of misdiagnosis cannot be eliminated. An ethical discussion of the question of whether PGD is acceptable at all-the 'desirability question'-is a rearguard action. Discussion must primarily focus on the conditions of exercising due caution in and the dynamics of PGD. PMID:19793305
Geraedts, J P M; De Wert, G M W R
Preimplantation Genetic Diagnosis (Embryo Screening) for Enlarged Vestibular Aqueduct due to SLC26A4 Mutation
Preimplantation genetic diagnosis (PGD) is used to analyze embryos genetically before their transfer into the uterus. For families with genetic diseases, PGD offers a chance to have an unaffected child, without facing termination of pregnancy. Although PGD has been performed for many monogenic disorders, such as cystic fibrosis and ?-thalassemia, the application of PGD to hereditary hearing impairment has not
Chen-Chi Wu; Shin-Yu Lin; Yi-Nin Su; Mei-Ya Fang; Shee-Uan Chen; Chuan-Jen Hsu
Preimplantation genetic diagnosis: State of the art
Preimplantation genetic diagnosis (PGD) is used to analyze embryos genetically before their transfer into the uterus. It was developed first in England in 1990, as part of progress in reproductive medicine, genetic and molecular biology. PGD offers couples at risk the chance to have an unaffected child, without facing termination of pregnancy. Embryos are obtained by in vitro fertilization with
Claire Basille; Ren� Frydman; Abdelwahab El Aly; Laetitia Hesters; Renato Fanchin; G�rard Tachdjian; Julie Steffann; Marc LeLorc�h; Nelly Achour-Frydman
[Genetic cancer syndromes and reproductive choice: dialogue between parents and politicians on preimplantation genetic diagnosis
Genetic cancer syndromes have identical clinical severity, limited therapeutic options, reduced life expectancy, and risks of genetic transmission, as do other genetic or congenital diseases for which prenatal genetic diagnosis or preimplantation genetic diagnosis (PGD) is allowed in the Netherlands. That was implied in the certification of one Dutch PGD centre at Maastricht University Hospital by the Dutch Ministry of
M. F. Niermeijer; C. E. M. de Die-Smulders; G. C. Page-Christiaens; G. M. W. R. de Wert
Outcome of preimplantation genetic diagnosis of translocations
Objective: To review 35 cases of preimplantation genetic diagnosis (PGD) of translocations with several methods, including telomeric probes.Design: Retrospective study.Setting: Clinical IVF laboratory.Patient(s): Thirty-five couples with one partner carrying a chromosomal translocation.Intervention(s): PGD of translocation after polar-body or embryo biopsy.Main Outcome Measure(s): Pregnancy outcome.Result(s): Several trends were observed. First, PGD can achieve a statistically significant reduction in spontaneous abortion, from
Santiago Munn�; Mireia Sandalinas; Tomas Escudero; Jingly Fung; Luca Gianaroli; Jacques Cohen
Preimplantation genetic diagnosis for inherited neurological disorders.
Preimplantation genetic diagnosis (PGD) is an option for couples at risk of having offspring with an inherited debilitating or fatal neurological disorder who wish to conceive a healthy child. PGD has been carried out for conditions with various modes of inheritance, including spinal muscular atrophy, Huntington disease, fragile X syndrome, and chromosomal or mitochondrial disorders, and for susceptibility genes for cancers with nervous system involvement. Most couples at risk of transmitting a genetic mutation would opt for PGD over prenatal testing and possible termination of a pregnancy. The aim of this Perspectives article is to assist neurologists in counselling and treating patients who wish to explore the option of PGD to enable conception of an unaffected child. PGD can be accomplished for most disorders in which the genetic basis is known, and we argue that it is time for clinicians and neurological societies to consider the evidence and to formulate guidelines for the responsible integration of PGD into modern preventative neurology. PMID:24866878
Tur-Kaspa, Ilan; Jeelani, Roohi; Doraiswamy, P Murali
Preimplantation genetic diagnosis in the mirror of ethics
Summary��\\u000a Legal and moral considerations hinder the introduction of preimplantation genetic diagnosis (PGD) in Germany. This article\\u000a presents and discusses the ethical arguments for and against PGD. In the autor's view neither the fact that PGD is not a well\\u000a established technique nor the danger that single-cell-analysis may lead to misdiagnosis convincingly demonstrates that PGD\\u000a is morally inacceptable. Inconsistencies in
Christian Netzer
The Ethics of Preimplantation Genetic Diagnosis
NSDL National Science Digital Library
In this video excerpt from NOVA, learn about the advantages, disadvantages, and ethical implications of preimplantation genetic diagnosis, or PGD, a technique used to screen embryos created through in vitro fertilization for diseases.
Foundation, Wgbh E.
Pregnancy and Birth After a Two-Step PGD: Polar Body Diagnosis for Hemophilia A and Array CGH on Trophectoderm Cells for Chromosomal Aberrations
PubMed Central
Objective: To demonstrate that a PGD program can be successfully established after the 2011 verdict of the German Bundestag concerning PGD. Material and Method: Eight years previously, the couple had had a daughter who suffered from clinically manifest hemophilia A due to an unbalanced X-inactivation, as well as microdeletion syndrome resulting in severe physical and mental disability. The couple wished to have a second child but refused the idea of a �trial� pregnancy. Given the indications for both, it was necessary to carry out polar body diagnosis (PBD) to rule out hemophilia A and, during the same cycle, a subsequent PGD on the blastocysts to rule out genetic aberrations. The PBD and PGD (trophectoderm biopsy, TEB) were performed after high-dosage ovarian stimulation and ICSI fertilization of the oocytes. A blastocyst was successfully transferred on day 6. Results: The patient conceived immediately. The pregnancy developed normally and the patient gave birth to a girl in the 40th week of pregnancy. Post-natal examinations showed that the baby is free from hemophilia A and is developing normally both physically and mentally. Conclusion: Establishment of a PGD program is now possible after legalization of PGD in Germany. It is possible to apply two investigative techniques in a single treatment cycle if multifactorial diagnosis is required.
Wurfel, W.; Suttner, R.; Shakeshaft, D.; Mayer, V.; Schoen, U.; Sendelbach, K.; Locher, M.; Koehler, U.; Fiedler, K.; Krusmann, G.; Holinski-Feder, E.
The politics of human embryo research and the motivation to achieve PGD
This article reports a historical study of factors influencing the achievement of clinical preimplantation genetic diagnosis (PGD) in 1990, 22 years after its first demonstration in animals. During the 1970s, research on PGD continued in large farm animals, but serious interest in human PGD was not evident until 1986. First, interest in PGD during the 1970s waned with the advent
Anastasia A. Theodosiou; Martin H. Johnson
Strategies and clinical outcome of 250 cycles of Preimplantation Genetic Diagnosis for single gene disorders
BACKGROUND: We report on our experience with preimplantation genetic diagnosis (PGD) for single gene disorders (SGDs), from 1999 to 2004, describing strategies and overall clinical outcome of 250 cycles in 174 couples for 23 different genetic conditions. METHODS: PGD cycles included 15 for autosomal dominant, 148 for autosomal recessive and 19 for X-linked SGDs. In addition, 68 cycles of PGD
F. Fiorentino; A. Biricik; A. Nuccitelli; R. De Palma; S. Kahraman; M. Iacobelli; V. Trengia; D. Caserta; M. A. Bonu; A. Borini; M. Baldi
Ethical issues in new uses of preimplantation genetic diagnosis
The use of preimplantation genetic diagnosis (PGD) to screen embryos for aneuploidy and genetic disease is grow- ing. New uses of PGD have been reported in the past year for screening embryos for susceptibility to cancer, for late-onset diseases, for HLA-matching for existing children, and for gender. These extensions have raised questions about their ethical acceptability and the adequacy of
John A. Robertson
First Successful Preimplantation Genetic Diagnosis in Singapore - Avoidance of ?-Thalassaemia Major
Introduction: We report on the fi rst successful preimplantation genetic diagnosis (PGD) in Singapore. Clinical Picture: A couple who are ?-thalassaemia carriers and have an affected daughter requested for PGD. Treatment: Two cycles of PGD were performed on the couple. ?-thalassaemia mutations were detected using a nested PCR and minisequencing strategy, and unaffected embryos were selected for transfer. Outcome: A
Christine Yap; Wen Wang; Mui Nee Lim; Samuel S Chong
Can preimplantation genetic diagnosis improve success rates in recurrent aborters with translocations?
Preimplantation genetic diagnosis (PGD) for people suffering recurrent miscarriages is increasingly being performed worldwide. However, there is limited information on whether PGD can improve success rates in translocation carriers. We therefore compared pregnancy outcomes between PGD and natural pregnancy cases, reviewing the clinical research data- base. No improvement in the success rate at the first oocyte retrieval was evident in
Mayumi Sugiura-Ogasawara; Kaoru Suzumori
Prenatal diagnosis yes, preimplantation genetic diagnosis no: a contradictory stance?
Preimplantation genetic diagnosis (PGD) after IVF with subsequent selection of embryos is accepted and practised in a number of European countries. In others, it is not only controversial but also forbidden by law. Since in these countries prenatal diagnosis (PND) with subsequent termination of pregnancy is legal and widely practised, a consistency problem arises. How can the discrepancy in regulation
Dieter Birnbacher
Analysis of Sex Chromosomes in Preimplantation Genetic Diagnosis for X-Chromosome-Linked Disorders
Preimplantation genetic diagnosis (PGD) is diagnostic tool to avoid inheritance of genetic disease by transferring unaffected embryos. Recently, PCR and FISH have been mainly applied to the diagnosis of single gene disorders and chromosomal abnormalities, respectively. Since with PGD, only a few cells are available for genetic tests, both gene and chromosomes analysis have to be obtained from the same,
Harumi Kubo; Yutaka Sasabe; Takayo Nishimura
Knowledge and attitudes towards preimplantation genetic diagnosis in Germany
BACKGROUND: Preimplantation genetic diagnosis (PGD) is a technique which is often related to emotional debates because of its ethical and social implications. Worldwide there are different forms of legislation; Germany constitutes an interesting case because of the historical background concerning eugenics and dealing with handi- capped persons at the time of national socialism. PGD is currently not legal but there
U. Meister; C. Finck; Y. Stobel-Richter; G. Schmutzer; E. Brahler
Social representations of stem cell research and preimplantation genetic diagnosis
The study examined public thinking about stem cell research and preimplantation genetic diagnosis (PGD) using social representation theory. Social representation theory is concerned with the movement of scientific knowledge from the realm of the specialist into lay knowledge. Participants were interviewed and the data analysed qualitatively. Three social representations were found for both stem cell research and PGD. For stem
BA Jones; CA McMahon
Preimplantation Genetic Diagnosis for Gender Selection in the United States.
National Technical Information Service (NTIS)
Preimplantation genetic diagnosis (PGD) of gender selection for non medical reasons has been considered an unethical procedure by several authors and agencies in the Western society on the basis of disrupting the sex ratio, being discriminatory againsts w...
G. Olivera J. Weier L. Silver P. Colls T. Escudero
Preimplantation genetic diagnosis: State of the ART 2011
For the last 20�years, preimplantation genetic diagnosis (PGD) has been mostly performed on cleavage stage embryos after the\\u000a biopsy of 1�2 cells and PCR and FISH have been used for the diagnosis. The main indications have been single gene disorders\\u000a and inherited chromosome abnormalities. Preimplantation genetic screening (PGS) for aneuploidy is a technique that has used\\u000a PGD technology to examine
Joyce C. Harper; Sioban B. SenGupta
Preimplantation genetic diagnosis of structural abnormalities
Preimplantation genetic diagnosis (PGD) of translocations can be achieved through a variety of methods. For female carriers, a possibility is by polar body biopsy and analysis of its metaphase chromosomes using painting probes. For male carriers or female carriers with terminal breakpoints, metaphase chromosomes can also be studied by fusing blastomeres to enucleated oocytes. Otherwise, interphase analysis of the translocation
Santiago Munne �
Preimplantation genetic diagnosis of pericentric inversions
Inversions are structural chromosome abnormalities that may be associated with infertility, multiple miscarriage and chromosomally unbalanced offspring. Preimplantation genetic diagnosis (PGD) with subtelomeric probes was used to select for transfer only those embryos that were normal or balanced for three pericentric inversions. In contrast to previous protocols the present procedure allows the detection of unbalanced embryos that might arise from
Michael Lee; John Stevens; Mireia Sandalinas
Preimplantation genetic diagnosis: does age of onset matter (anymore)?
The identification and avoidance of disease susceptibility in embryos is the most common goal of preimplantation genetic diagnosis\\u000a (PGD). Most jurisdictions that accept but regulate the availability of PGD restrict it to what are characterized as �serious�\\u000a conditions. Line-drawing around seriousness is not determined solely by the identification of a genetic mutation. Other factors\\u000a seen to be relevant include: impact
Timothy Krahn
Whole genome amplification in preimplantation genetic diagnosis
Preimplantation genetic diagnosis (PGD) refers to a procedure for genetically analyzing embryos prior to implantation, improving\\u000a the chance of conception for patients at high risk of transmitting specific inherited disorders. This method has been widely\\u000a used for a large number of genetic disorders since the first successful application in the early 1990s. Polymerase chain reaction\\u000a (PCR) and fluorescent in situ
Ying-ming Zheng; Ning Wang; Lei Li; Fan Jin
Preimplantation genetic diagnosis and reproductive autonomy.
This paper examines how reproductive autonomy of women and couples is affected by the availability of preimplantation genetic diagnosis (PGD). Libertarians have argued that PGD enhances reproductive autonomy by increasing options available to prospective parents. We acknowledge that PGD presents prospective parents with more options, but note that the libertarian view of reproductive autonomy overlooks important aspects of the social practice of PGD by focusing too narrowly on the absence of explicit constraints as the main guarantee of reproductive autonomy. We endorse instead a feminist relational account of autonomy in which exercising autonomy involves paying attention to the relevant contextual features that configure and shape prospective parents' choices and understanding of their reproductive options. On this view, PGD has a negative potential to constrain reproductive autonomy. We recommend that this negative potential be addressed by making sure the availability of PGD is accompanied by increased attention to the relevant educational needs of prospective parents and the general public, as well as the availability of adequate social supports for people with disabilities, their care providers and families. PMID:19891846
Krahn, T; Wong, S I
Ethics and the future of preimplantation genetic diagnosis
The future growth of preimplantation genetic diagnosis (PGD) will depend on refinements in genetic knowledge and genetic analysis of blastomeres. Equally important, however, is an acceptance of the ethical legitimacy of parents using technologies to select genetic traits of offspring. Objections based on embryo status, the giftedness of reproduction, eugenics, and protecting the child's welfare are not convincing grounds to
John A Robertson
Preimplantation genetic diagnosis: public policy and public attitudes
In vitro fertilization (IVF) and genetic testing each present a host of issues that are technically, legally, and ethically complicated. Nevertheless, the worlds of genetic testing and assisted reproduction have converged with the advent of preimplantation genetic diagnosis (PGD), which allows par- ents to choose which embryos to transfer to the mother's womb on the basis of genetic test results.
Kathy L. Hudson
PGD for germline mosaicism.
The aim of this study was to develop and perform a preimplantation genetic diagnosis (PGD) assay discriminating between wild-type and mutant alleles in two families with germline mosaicism. Family 1 had two children affected with severe myoclonic epilepsy (SCNA1A del exons 1-22). Family 2 had two children with tuberous sclerosis (TSC2 C1327T) and two healthy children. Neither mutation was detected in genomic DNA derived from the parents in either family. Informative microsatellite markers flanking SCNA1A and TSC2 along with the identified mutations were used to construct haplotypes. For tuberous sclerosis, single spermatozoa were analysed using a multiplex assay that included six informative markers and the TSC2 mutation. In family 1, deletion in the maternal allele was detected in the affected child. In family 2, both affected children and one healthy child shared the same paternal allele. To confirm mutant paternal transmission, single spermatozoa were analysed for the mutation along with six markers. Of 44 single spermatozoa, four showed the mutant T allele, allowing linkage between the mutation and the genetic markers. Both families delivered healthy children following IVF/PGD. In conclusion, germline mosaicism complicates allele assignment when constructing haplotypes for PGD. Sperm analysis is a useful tool for verifying allelic linkage. PMID:22884613
Altarescu, Gheona; Beeri, Rachel; Eldar-Geva, Talia; Varshaver, Irit; Margalioth, Ehud J; Levy-Lahad, Ephrat; Renbaum, Paul
Polymorphism at the G6pd and 6Pgd loci in Drosophila melanogaster. IV. Genetic factors modifying enzyme activity.
Different homozygous lines of similar genotype with respect to G6pd and 6Pgd were shown to have different enzyme activities for G6PD and 6PGD. Crosses between high and low lines suggested that there were modifying genes present on the autosomes, while others were probably located on the X chromosome. Allelic variation within each electrophoretic class of G6pd and 6Pgd might, however, also have contributed to this variation. An experiment on adaptation to sodium octanoate demonstrated that in adapted flies selection for lower enzyme activity had occurred, which provided further evidence for the existence of genetic differences in activity. Furthermore, a strong positive correlation between the activities of G6PD and 6PGD was found for each genotype. Since no correlation was found between MDH and the two enzymes G6PD and 6PGD, it could be concluded that this correlation was probably rather specific for G6PD and 6PGD. Interaction between genotypes with respect to activity was also found. It was shown that the variation at 6Pgd influenced the activity of G6PD within a genotype. The data are discussed in relation to fitness differences presented in foregoing articles. PMID:6781470
Bijlsma, R
First systematic experience of preimplantation genetic diagnosis for de-novo mutations
Standard preimplantation genetic diagnosis (PGD) cannot be applied for de-novo mutations (DNM), because neither origin nor relevant haplotypes are available for testing in single cells. PGD strategies were developed for 80 families with 38 genetic disorders, determined by 33 dominant, three recessive and two X-linked DNM. All three recessive mutations were of paternal origin, while of 93 dominant mutations, 40
Svetlana Rechitsky; Ekaterina Pomerantseva; Tatiana Pakhalchuk; Dana Pauling; Oleg Verlinsky; Anver Kuliev
Preimplantation genetic diagnosis (PGD), a modified version of in vitro fertilization in which individual embryos are screened for specific genetic characteristics prior to implantation, provides a powerful way for parents suffering from infertility to increase their chances of having healthy children. In its various forms, PGD allows parents to screen for gender, providing a means for avoiding X-linked diseases, chromosomal
Aaron D. Levine
Attitudes towards Preimplantation Genetic Diagnosis�a German and Japanese comparison
Preimplantation Genetic Diagnosis (PGD) is one form of applied human genetics. In many countries this technological procedure is allowed and already practiced. In other, relatively rare cases, PGD is prohibited like in Germany or allowed only under very strict conditions like in Japan. Often, this technological application is controversially discussed because of its ethical and social implications (Meister et al.,
Kerstin W�stner; Ulrich Heinze
Anticipating issues related to increasing preimplantation genetic diagnosis use: a research agenda
Increasing use of preimplantation genetic diagnosis (PGD) poses numerous clinical, social, psychological, ethical, legal and policy dilemmas, many of which have received little attention. Patients and providers are now considering and using PGD for a widening array of genetic disorders, and patients may increasingly seek �designer babies.� In the USA, although governmental oversight policies have been discussed, few specific guidelines
Robert Klitzman; Paul S Appelbaum; Wendy Chung; Mark Sauer
Preimplantation genetic diagnosis of haemophilia.
Preimplantation genetic diagnosis (PGD) aims to increase the number of options available to couples who could have a child affected with haemophilia and reduce the anxiety these couples often associate with reproduction. The female partner must undergo an in vitro fertilization cycle, and the eggs or embryos are then biopsied. Embryos which are unaffected by haemophilia can then be transferred to the uterus. The clear advantage of this technique is that the woman knows from the very beginning that the pregnancy is unaffected by haemophilia, and she can avoid conventional invasive prenatal diagnosis and the difficult decision on whether or not to terminate an affected pregnancy. Several strategies for this single cell genetic diagnosis have been described. These include embryonic sexing using polymerase chain reaction, embryonic sexing using fluorescent in situ hybridization, specific diagnosis using restriction enzymes, sequencing and haplotype analysis. Over the years, PGD has attracted much ethical commentary, both supportive and critical, regarding the fundamental principles of embryo selection and destruction. New scientific advances and their potential applications are considered. PMID:19036080
Lavery, Stuart
[Bioethics and biojuridical evaluation of preimplantation genetic diagnosis in Spain].
Spanish law 14/2006 introduced the necessary legal platform for scientific use and medical application of preimplantatory genetic diagnosis (PGD) in the Country. Since it was approved, there have been some cases of babies that have been born by artificial reproductive techniques using PGD. The most recent case was the first ?double hope baby? who was free of beta-thalasemy and a histocompatible donor for his sick older brother. This situation, new in Spain, introduced a new context that confirmed the eugenic consequences of this kind of techniques. This article evaluates PGD starting by a multidisciplinary analysis that covers the technical aspects of PGD and the different arguments which support or detract from it. In summary, the technique involves strong eugenic aspects supported by poor arguments. The need to use valid premises when making legal judgments on biomedical procedures with social consequences, lead us to warn of the consequences of using PGD. PMID:20886913
Vivanco, Luis; Mart�nez, Alfredo; Jouve de la Barreda, Nicol�s
The Benefits of Preimplantation Genetic Diagnosis for Chromosomal Aneuploidy
\\u000a Despite recent controversy, preimplantation genetic diagnosis (PGD) for aneuploidies is becoming a practical means in assisted\\u000a reproduction technology (ART) to select embryos with higher developmental potential for improving in vitro fertilization (IVF)\\u000a effectiveness. Available PGD experience for chromosomal disorders shows that at least half of the oocytes and embryos obtained\\u000a from poor prognosis IVF patients are aneuploid and clearly should
Anver Kuliev; Yury Verlinsky
Jewish perspectives on the use of preimplantation genetic diagnosis.
This article presents an analysis of the ethical considerations raised by preimplantation genetic diagnosis (PGD) from a Jewish perspective. It weighs the Jewish imperatives to pursue good health against a number of harms that may follow from the expanded use of PGD technology, including increased medical risk to the mother, the destruction of embryos and possible emotional harm to the child born from this procedure. It pays special attention to the potential harms that may befall those in society who do not have access to PGD or who choose not to employ it. PMID:18076520
Popovsky, Mark
Comparison of attitudes regarding preimplantation genetic diagnosis among patients with hereditary cancer syndromes.
Preimplantation genetic diagnosis (PGD) allows couples to avoid having a child with an inherited condition, potentially reducing cancer burden in families with a hereditary cancer predisposition. This study investigated and compared awareness and acceptance of PGD among patients with different hereditary cancer syndromes. Questionnaires were mailed to 984 adults with hereditary breast and ovarian cancer, Lynch syndrome, familial adenomatous polyposis, or multiple endocrine neoplasia type 1 or 2. Associations between clinical, demographic, and psychosocial factors and awareness and acceptance of PGD were examined. Of 370 respondents (38�% return rate), 28�% felt their syndrome impacted family planning, 24�% were aware of PGD, 72�% felt that PGD should be offered, 43�% would consider using PGD, and 29�% were uncertain. Family experience and syndrome-specific characteristics, such as disease severity, quality of life and availability of medical interventions as well as gender, family planning stage, and religiosity impact perceptions of the acceptability of PGD, though a high level of uncertainty exists. Hereditary cancer patients lack awareness of PGD despite feeling that PGD should be offered, highlighting the need for education on this topic. While we found attitudes about the acceptability of PGD to be generally similar to those reported in the literature and of genetics and ethics experts, we observed similarities and differences between syndromes that provide insight into why some hereditary cancer patients may find PGD more acceptable than others. PMID:24072553
Rich, Thereasa A; Liu, Mei; Etzel, Carol J; Bannon, Sarah A; Mork, Maureen E; Ready, Kaylene; Saraiya, Devki S; Grubbs, Elizabeth G; Perrier, Nancy D; Lu, Karen H; Arun, Banu K; Woodard, Terri L; Schover, Leslie R; Litton, Jennifer K
Double locus analysis of chromosome 21 for preimplantation genetic diagnosis of aneuploidy
Preimplantation genetic diagnosis (PGD) of numerical chromosome abnormalities significantly reduces spontaneous abortions and may increase pregnancy rates in women of advanced maternal age undergoing in vitro fertilization. However, the technique has an error rate of around 10% and trisomy 21 conceptions have occurred after PGD. To further reduce the risk of transferring trisomy 21 embryos to the patient, we designed
M. C. Magli; M. Sandalinas; T. Escudero; L. Morrison; A. P. Ferraretti; L. Gianaroli
The beneficial effects of preimplantation genetic diagnosis for aneuploidy support extensive clinical application
The aim of this study was to evaluate the clinical impact of preimplantation genetic diagnosis (PGD) for aneuploidy on 193 patients who subsequently achieved 208 clinical pregnancies, in relation to their reproductive history. The 208 clinical pregnancies included in the study resulted from 1029 assisted conception cycles in combination with PGD for aneuploidy in 740 couples with a history of
Luca Gianaroli; M Cristina Magli; Anna P Ferraretti; Carla Tabanelli; Vincenzo Trengia; Valeria Farfalli; Giorgio Cavallini
Preimplantation genetic diagnosis as an alternative to amniocentesis and chorionic villus sampling: psychosocial and ethical aspects
Social and ethical considerations play an increasing role in decisions about the use of diagnostic technologies. In this article expert opinions of a medical�biological and a social�ethical panel on psychosocial, ethical and social aspects of preimplantation genetic diagnosis (PGD) are discussed. PGD is a new diagnostic technology for identifying chromosomal or single gene defects, which is now available as a
M. M Vergeer; F van Balen; E Ketting
Preimplantation genetic diagnosis in Saudi Arabia.
Preimplantation genetic diagnosis (PGD) testing is the practice of obtaining a cellular biopsy sample from a developing human oocyte or embryo, acquired via a cycle of in vitro fertilization (IVF); evaluating the genetic composition of this sample; and using this information to determine which embryos will be optimal for subsequent uterine transfer. PGD has become an increasingly useful adjunct to IVF procedures. The ability to provide couples who are known carriers of genetic abnormalities the opportunity to deliver healthy babies has opened a new frontier in reproductive medicine. The purpose of the PGD is enables us to choose which embryos will be implanted into the mother. In the present study 137 families who had undergone IVF at Habib Medical Centre, were enrolled for the PGD analysis. The couple visited the clinic for the sex selection, recurrent fetal loss and with the recurrent IVF failure. 802 embryos were tested by the biopsy method and 512 are found to be normal and 290 were abnormal embryos. In this study only 24% of the embryos were transferred and the remaining was not transferred because of the abnormalities or undesired sex of the embryos. The structural and numerical abnormalities were found to be 16.8%. PMID:23750087
Abotalib, Zeinab
Preimplantation genetic diagnosis in Saudi Arabia
Preimplantation genetic diagnosis (PGD) testing is the practice of obtaining a cellular biopsy sample from a developing human oocyte or embryo, acquired via a cycle of in vitro fertilization (IVF); evaluating the genetic composition of this sample; and using this information to determine which embryos will be optimal for subsequent uterine transfer. PGD has become an increasingly useful adjunct to IVF procedures. The ability to provide couples who are known carriers of genetic abnormalities the opportunity to deliver healthy babies has opened a new frontier in reproductive medicine. The purpose of the PGD is enables us to choose which embryos will be implanted into the mother. In the present study 137 families who had undergone IVF at Habib Medical Centre, were enrolled for the PGD analysis. The couple visited the clinic for the sex selection, recurrent fetal loss and with the recurrent IVF failure. 802 embryos were tested by the biopsy method and 512 are found to be normal and 290 were abnormal embryos. In this study only 24% of the embryos were transferred and the remaining was not transferred because of the abnormalities or undesired sex of the embryos. The structural and numerical abnormalities were found to be 16.8%.
Ethical aspects of pre-implantation genetic diagnosis
Pre-implantation genetic diagnosis (PGD) presents several ethical dilemmas, some akin to those found in prenatal diagnosis, and others more specific to the technique, which requires in-vitro fertilisation and creates embryos in vitro. Here, the status of the embryo is central to the dilemmas concerning its selection, possible destruction or use in research, and the fate of carrier embryos. Furthermore, the
Fran�oise Shenfield
Preimplantation Genetic Diagnosis�An Overview
Since the early 1990s, preimplantation genetic diagnosis (PGD) has been expanding in scope and applications. Selection of female embryos to avoid X-linked disease was carried out first by polymerase chain reaction, then by fluorescence in situ hybridization (FISH), and an ever-increasing number of tests for monogenic diseases have been developed. Couples with chromosome rearrangements such as Robertsonian and reciprocal translocations
Caroline Mackie Ogilvie; Peter R. Braude; Paul N. Scriven
Extending preimplantation genetic diagnosis: the ethical debate. Ethical issues in new uses of preimplantation genetic diagnosis.
The use of preimplantation genetic diagnosis (PGD) to screen embryos for aneuploidy and genetic disease is growing. New uses of PGD have been reported in the past year for screening embryos for susceptibility to cancer, for late-onset diseases, for HLA-matching for existing children, and for gender. These extensions have raised questions about their ethical acceptability and the adequacy of regulatory structures to review new uses. This article describes current and likely future uses of PGD, and then analyses the ethical issues posed by new uses of PGD to screen embryos for susceptibility and late-onset conditions, for HLA-matching for tissue donation to an existing child, and for gender selection. It also addresses ethical issues that would arise in more speculative scenarios of selecting embryos for hearing ability or sexual orientation. The article concludes that except for sex selection of the first child, most current extensions of PGD are ethically acceptable, and provides a framework for evaluating future extensions for nonmedical purposes that are still speculative. PMID:12615807
Robertson, John A
Perspectives of couples with high risk of transmitting genetic disorders
Objective: To investigate the preference for preimplantation genetic diagnosis (PGD) as an alternative to prenatal diagnosis (PND) in a large group of couples representing a wide array of genetic disorders. We also investigated the couple's familiarity with PGD and presented time trade-off scenarios for PGD versus PND, as PGD treatment is regularly accompanied by waiting lists. Design: Questionnaire study. Setting:
Anna M. Musters; Moniek Twisk; Nico J. Leschot; Cor Oosterwijk; Johanna C. Korevaar; Sjoerd Repping; Fulco van der Veen; Mariette Goddijn
Pandora's box: ethics of PGD for inherited risk of late-onset disorders
Until recently, the primary use of preimplantation genetic diagnosis (PGD) has been the selection of embryos to avoid lethal or debilitating gene mutations or abnormal chromosome complement. PGD can be used to reduce the risk of transferring to the uterus an embryo with Down syndrome, and parents who are carriers of severe genetic diseases may choose to avoid having children
Ray Noble; Gulam Bahadur; Mohammad Iqbal; Arnab Sanyal
Preimplantation Genetic Diagnosis in Marfan Syndrome
Marfan syndrome (MFS) is a systemic hereditable disorder of the connective tissue with mainly cardiovascular manifestations, such as aortic dilatation and dissection. We describe a case of a 32-year-old Caucasian woman, clinically asymptomatic with MFS who presented for genetic consultation to prevent the transmission of disease to her offspring. She underwent controlled ovarian stimulation (COH), in vitro fertilization (IVF) combined with preimplantation genetic diagnosis (PGD), and a singleton pregnancy with positive fetal heart rate was revealed. At 34 weeks' gestation she delivered vaginally a healthy premature male infant weighting 2440 gr. The patient remained asymptomatic during pregnancy, delivery, and 3 months postpartum. It is has to be mentioned that the availability of PGD is essential to prevent the transmission of disease to the next generation.
Vlahos, N. F.; Triantafyllidou, O.; Vitoratos, N.; Grigoriadis, C.; Creatsas, G.
Successful application of the strategy of blastocyst biopsy, vitrification, whole genome amplification, and thawed embryo transfer for preimplantation genetic diagnosis of neurofibromatosis type 1
ObjectivePreimplantation genetic diagnosis (PGD) offers an alternative for women to carry an unaffected fetus risk of hereditary diseases. Trophectoderm biopsy may provide more cells for accurate diagnosis. However, the time allowed for transportation of the specimens to the laboratory and performance of molecular diagnosis is limited. We designed a PGD program of trophectoderm biopsy, vitrification of blastocysts, whole genome amplification
Yi-Lin Chen; Chia-Cheng Hung; Shin-Yu Lin; Mei-Ya Fang; Yi-Yi Tsai; Li-Jung Chang; Chien-Nan Lee; Yi-Ning Su; Shee-Uan Chen; Yu-Shih Yang
PGD for monogenic disorders: aspects of molecular biology.
Preimplantation genetic diagnosis (PGD) for monogenic diseases has known a considerable evolution since its first application in the early 1990s. Especially the technical aspects of the genetic diagnosis itself, the single-cell genetic analysis, has constantly evolved to reach levels of accuracy and efficiency nearing those of genetic diagnosis on regular DNA samples. In this review, we will focus on the molecular biological techniques that are currently in use in the most advanced centers for PGD for monogenic disorders, including multiplex polymerase chain reaction (PCR) and post-PCR diagnostic methods, whole genome amplification (WGA) and multiple displacement amplification (MDA). As it becomes more and more clear that when it comes to ethically difficult indications, PGD goes further than prenatal diagnosis (PND), we will also briefly discuss ethical issues. PMID:19101953
Spits, Claudia; Sermon, Karen
[Preimplantation genetic diagnosis. Ethical, social and legal aspects].
Preimplantation genetic diagnosis (PGD) undertakes an examination of an embryo outside the mother's womb subsequent to artificial insemination in order to identify a potential genetic and chromosomal impairment of that embryo. PGD is not being practiced in the Federal Republic of Germany since it cannot be reconciled with the provisions of the Embryo Protection Law. Objections have been raised against PGD based on ethical, religious and feminist arguments as well as on the grounds of legal framework policy. The essence of those objections relates to the fact that this method relativises the inviolability of the embryo in its early stages. Even human dignity itself is considered in danger. However, those objections have themselves caused demur. A variety of ethical reasons make it appear conceivable to allow PGD under narrowly defined conditions in medically founded cases. PGD can be used to the benefit of the health of both the pregnant mother and the expected children. In case PGD should be permitted, it would have to be within the framework of medical and sociopsychological counselling. PMID:17225987
Kress, Hartmut
Preimplantation Genetic Diagnosis for Severe Albright Hereditary Osteodystrophy
Context: Preimplantation genetic diagnosis (PGD) enables the selection of embryos without mu- tations for implantation and has not been described to our knowledge for mutations in GNAS. Phocomelia in a patient with Albright hereditary osteodystrophy (AHO) has also not been previ- ously described. Objective: The aim of this study was to identify a GNAS mutation in a patient with a
Steven A. Lietman; James Goldfarb; Nina Desai; Michael A. Levine
Preimplantation genetic diagnosis of Marfan syndrome using multiple displacement amplification
Objective: To evaluate the use of multiple displacement amplification (MDA) for whole-genome amplification in the preimplantation genetic diagnosis (PGD) of Marfan syndrome. Design: Multiple displacement amplification was used to amplify the whole-genome directly from a single cell. The MDA product was used for polymerase chain reaction (PCR) analysis of five different loci. At this point MDA was used to develop
Bel�n Lled�; Francisco M. Gal�n; Rafael Bernabeu
Provision and quality assurance of preimplantation genetic diagnosis in Europe
Preimplantation genetic diagnosis (PGD) is now well established and provided in many European countries. However, regulations, professional standards and accreditation requirements can differ notably. Furthermore, no comprehensive independent data exist either about practice and provision in Europe or about the quality assurance practices and procedures designed to optimize the quality of the results. Consequently, a study was launched to obtain
Anniek Corveleyn; Michael A Morris; Elisabeth Dequeker; Karen Sermon; James Lawford Davies; Guillermo Anti�olo; Andreas Schmutzler; Jiri Vanecek; Nick Nagels; Eleni Zika; Francesc Palau; Dolores Ibarreta
Meiotic and mitotic nondisjunction: lessons from preimplantation genetic diagnosis
Direct testing of the outcome of the first and second meiotic divisions has become possible with the introduction of preimplantation genetic diagnosis (PGD) for aneuploidies. Testing of oocytes by fluorescent in situ hybridization (FISH) analysis of the first and second polar bodies showed that more than half of oocytes from the IVF patients aged 35 years and older had chromosomal
Pregnancy following preimplantation genetic diagnosis for Crouzon syndrome
Crouzon syndrome is a dominantly inherited craniosynostosis syndrome which is caused by mutations in the fibroblast growth factor receptor 2 gene (FGFR2). However, a specific point mutation in the FGFR3 gene has also been shown to result in Crouzon syndrome associated with acanthosis nigricans. We report here the first method for preimplantation genetic diagnosis (PGD) of Crouzon syndrome based on
P. M. Abou-Sleiman; A. Apessos; J. C. Harper; P. Serhal; J. D. A. Delhanty
Extending preimplantation genetic diagnosis: medical and non-medical uses
New uses of preimplantation genetic diagnosis (PGD) to screen embryos prior to transfer raise ethical, legal, and policy issues that deserve close attention. Extensions for medical purposes, such as to identify susceptibility genes, late onset disease, and human leukocyte antigen (HLA) matching, are usually ethically acceptable. Whether embryo screening for gender, perfect pitch, or other non-medical characteristics are also acceptable
J A Robertson
Saviour embryos? Preimplantation genetic diagnosis as a therapeutic technology
The creation of �saviour siblings� is one of the most controversial uses of preimplantation genetic diagnosis (PGD). This paper outlines and invites ethical discussion of an extension of this technology, namely, the creation of �saviour embryos� to serve as a source of stem cells to be used in potentially life-saving therapy for an existing child. A number of analogies between
Robert Sparrow; David Cram
Is embryo research and preimplantation genetic diagnosis ethical?
The legal position in the UK on embryo research and preimplantation genetic diagnosis (PGD) is outlined and contrasted with the position in other EU countries. The �gradualist� position of the UK on the moral status of the embryo is defended on the basis of an argument that precaution must be applied in proportion to the degree to which the embryo
Deryck Beyleveld
Successful Preimplantation Genetic Diagnosis of Hb Bart's Hydrops Fetalis in Singapore after Fresh and Frozen Embryo Replacement Cycles
Introduction: We report the fi rst successful preimplantation genetic diagnosis (PGD) for Hb Bart's hydrops fetalis in Singapore, involving both fresh and frozen embryo replacement cycles. Clinical Picture: Two couples who were carriers of the Southeast Asian type double gene deletion (-- SEA deletion carriers) requested for PGD. Couple A had 2 previous affected pregnancies, while couple B have a
Christine Yap; Wen Wang; Wei Chin Tan; Mui Nee Lim; Samuel S Chong
State Intervention in Couples� Reproductive Decisions: Socioethical Reflections Based on the Practice of Preimplantation Genetic Diagnosis in France
Adopting socioethical and anthropological perspectives, this article addresses the impact of state intervention in the reproductive life of couples who consult for preimplantation genetic diagnosis (PGD) in France. Our main objective is to identify and analyze the socioethical problems flowing from French legislation as related to PGD and from its implementation. Methods included review and analysis of the relevant literature,
Chantal Bouffard; Julie-Kim Godin; B�n�dicte B�vi�re
Preimplantation genetic diagnosis in female and male carriers of reciprocal translocations: clinical outcome until delivery of 312 cycles
Carriers of reciprocal translocations (rcp) are known to be at risk for reproductive difficulties. Preimplantation genetic diagnosis (PGD) is one of the options these carriers have to try in order to fulfil their desire to have a child. In the present study, we retrospectively looked at the results of 11 years (1997�2007) of PGD for rcp in our center to
Kathelijn Keymolen; Catherine Staessen; Willem Verpoest; Inge Liebaers; Maryse Bonduelle
PGD gender selection for non-Mendelian disorders with unequal sex incidence
Preimplantation genetic diagnosis (PGD) was originally developed for couples whose potential offspring were at risk of severe Mendelian disorders, but has since been extended to other indications. One possible use of PGD is to perform gender selection for couples whose offspring are at increased risk of disorders that do not follow Mendelian inheri- tance, but which are substantially more common
David J. Amor; Carolyn Cameron
[Ten years' experience of preimplantation genetic diagnosis in Paris: remaining obstacles and potential solutions].
Preimplantation genetic diagnosis (PGD) has been authorized in France since 1999. Encouraging results have been obtained during the past 10 years in our Paris center, where 832 patients have undergone 1056 IVF-PGD procedures. With the advent of new techniques for the identification of genetic disease markers, our center can now offer PGD procedures for aneuploidy and 75 single-gene diseases. New indications for PGD have also been developed, such as mitochondrial DNA diseases, amyloid neuropathy, pulmonary arterial hypertension, and HLA typing The implantation rate is currently 29,6% and, by 31 December 2009, 151 healthy babies had been born. Unfortunately, demand for PGD procedures far outstrips available technical capacity, and the waiting period is longer than 18 months. Increased funding is urgently needed PMID:22375366
Frydman, Ren�; Achour-Frydman, Nelly; Steffann, Julie; Lamazou, Fred�ric; Fanchin, Renato; Burlet, Philippe; Gigarel, Nadine; Romana, Serge; Bonnefont, Jean-Paul; Le Lorch, Marc; Kerbrat, Violaine; Hesters, Laetitia; Munnich, Arnold; Vekemans, Michel
Anticipating issues related to increasing preimplantation genetic diagnosis use: a research agenda.
Increasing use of preimplantation genetic diagnosis (PGD) poses numerous clinical, social, psychological, ethical, legal and policy dilemmas, many of which have received little attention. Patients and providers are now considering and using PGD for a widening array of genetic disorders, and patients may increasingly seek 'designer babies.' In the USA, although governmental oversight policies have been discussed, few specific guidelines exist. Hence, increasingly, patients and providers will face challenging ethical and policy questions of when and for whom to use PGD, and how it should be financed. These issues should be better clarified and addressed through collection of data concerning the current use of PGD in the USA, including factors involved in decision making about PGD use, as well as the education of the various communities that are, and should be, involved in its implementation. Improved understanding of these issues will ultimately enhance the development and implementation of future clinical guidelines and policies. PMID:18644221
Klitzman, Robert; Appelbaum, Paul S; Chung, Wendy; Sauer, Mark
FISH for Pre-implantation Genetic Diagnosis
Pre-implantation genetic diagnosis (PGD) is an established alternative to pre-natal diagnosis, and involves selecting pre-implantation embryos from a cohort generated by assisted reproduction technology (ART). This selection may be required because of familial monogenic disease (e.g. cystic fibrosis), or because one partner carries a chromosome rearrangement (e.g. a two-way reciprocal translocation). PGD is available for couples who have had previous affected children, and/or in the case of chromosome rearrangements, recurrent miscarriages, or infertility. Oocytes aspirated following ovarian stimulation are fertilized by in vitro immersion in semen (IVF) or by intracytoplasmic injection of an individual spermatozoon (ICSI). Pre-implantation cleavage-stage embryos are biopsied, usually by the removal of a single cell on day 3 post-fertilization, and the biopsied cell is tested to establish the genetic status of the embryo. Fluorescence in situ hybridization (FISH) on the fixed nuclei of biopsied cells with target-specific DNA probes is the technique of choice to detect chromosome imbalance associated with chromosome rearrangements, and to select female embryos in families with X-linked disease for which there is no mutation-specific test. FISH has also been used to screen embryos for spontaneous chromosome aneuploidy (also known as PGS or PGD-AS) in order to try and improve the efficiency of assisted reproduction; however, the predictive value of this test using the spreading and FISH technique described here is likely to be unacceptably low in most people's hands and it is not recommended for routine clinical use. We describe the selection of suitable probes for single-cell FISH, spreading techniques for blastomere nuclei, and in situ hybridization and signal scoring, applied to PGD in a clinical setting.
Scriven, Paul N.; Kirby, Toby L.; Ogilvie, Caroline Mackie
A 'healthy baby': The double imperative of preimplantation genetic diagnosis.
This article reports from a study exploring the social processes, meanings and institutions that frame and produce 'ethical problems' and clinical dilemmas for practitioners, scientists and others working in the specialty of preimplantation genetic diagnosis (PGD). A major topic in the data was that, in contrast to IVF, the aim of PGD is to transfer to the woman's womb only those embryos likely to be unaffected by serious genetic disorders; that is, to produce 'healthy babies'. Staff described the complex processes through which embryos in each treatment cycle must meet a double imperative: they must be judged viable by embryologists and 'unaffected' by geneticists. In this article, we focus on some of the ethical, social and occupational issues for staff ensuing from PGD's double imperative. PMID:20051429
Ehrich, Kathryn; Williams, Clare
Attitude towards pre-implantation genetic diagnosis for hereditary cancer
The use of pre-implantation genetic diagnosis (PGD) for hereditary cancer is subject to on-going debate, particularly among\\u000a professionals. This study evaluates the attitude towards PGD and attitude-associated characteristics of those concerned: family\\u000a members with a hereditary cancer predisposition. Forty-eight Von Hippel-Lindau and 18 Li�Fraumeni Syndrome families were identified\\u000a via the 9 family cancer clinics in the Netherlands. In total, 216
Chantal Lammens; Eveline Bleiker; Neil Aaronson; Annette Vriends; Margreet Ausems; Maaike Jansweijer; Anja Wagner; Rolf Sijmons; A. M. W. van den Ouweland; Rob van der Luijt; Liesbeth Spruijt; Encarna G�mez Garc�a; Mari�lle Ruijs; Senno Verhoef
[Embryonal genetic diagnosis and reproductive freedom in assisted procreation].
This article analyses the repercussions that the Preimplantational Genetic Diagnosis (PGD) has in the bioethical as well as legal fields in relation with the so-called "reproductive freedom" of the couple. Besides analysing the legal situation of this technique in Spain as well as other surrounding States, the article studies the problems associated with some scenarios of PGD, such as the use in the selection of sex, for therapeutic purposes for third parties, in relation with diseases of a possible late onset, multifactorial or of a variable phenotype expression and for the selection of embryos affected by a disease or disability. All are based on real clinical cases. PMID:17393795
Abell�n, Fernando
Strategies and outcomes of PGD of familial adenomatous polyposis
Owing to adult onset of hereditary cancer, prenatal diagnosis (PND) raises numerous ethical issues on the acceptability to termi- nate an affected pregnancy (TOP). PND for these disorders is often considered as unacceptable by couples as well as geneticists and legal or ethical authorities, but preimplantation genetic diagnosis (PGD), even if subject to controversy, seems to be a more acceptable
C. Moutou; N. Gardes; J.-C. Nicod; S. Viville
Preimplantation genetic diagnosis for monogenic diseases: overview and emerging issues.
Preimplantation genetic diagnosis (PGD) is an established reproductive option for couples at risk of conceiving a pregnancy affected with a known genetic disease, who wish to avoid an (additional) affected child, termination of pregnancy or recurrent miscarriages. Early technologies concentrated on different approaches to direct mutation testing for monogenic diseases using single cell PCR protocols, or sex selection by fluorescent in situ hybridization for X-linked monogenic disease. Development of multiplex fluorescent PCR allowed simultaneously testing of linked markers alongside the mutation test, increasing the accuracy by controlling for contamination and identifying allele drop-out. The advent of highly effective whole genome amplification methods has opened the way for new technologies such as preimplantation genetic haplotyping and microarrays, thus increasing the number of genetic defects that can be detected in preimplantation embryos; the number of cases carried out and the new indications tested increases each year. Different countries have taken very different approaches to legislating and regulating PGD, giving rise to the phenomenon of reproductive tourism. PGD is now being performed for scenarios previously not undertaken using prenatal diagnosis, some of which raise significant ethical concerns. While PGD has benefited many couples aiming to have healthy children, ethical concerns remain over inappropriate use of this technology. PMID:17187482
Renwick, Pamela; Ogilvie, Caroline Mackie
Choosing between possible lives: legal and ethical issues in preimplantation genetic diagnosis.
This article critically appraises the current legal scope of the principal applications of preimplantation genetic diagnosis (PGD). This relatively new technique, which is available to some parents undergoing in vitro fertilization (IVF) treatment, aims to ensure that a child is not born with a seemingly undesirable genetic condition. The question addressed here is whether there should be serious reasons to test for genetic conditions in embryos in order to be able to select between them. The Human Fertilisation and Embryology Authority and the Human Genetics Commission have decided that there should be such reasons by broadly aligning the criteria for PGD with those for selective abortion. This stance is critically explored, as are its implications for the possible use of PGD to select either against or for marginal features or for significant traits. The government is currently reviewing the legal scope and regulation of PGD. PMID:17340769
Scott, Rosamund
[Preimplantation genetic diagnosis--developments to expect?].
Preimplantation genetic diagnosis (PGD) has been practiced for over 20 years. It prevents the birth of children with serious genetic diseases by selecting healthy embryos before pregnancy. In France, the initial indications of PGD have been extended in two directions: on the one hand, to allow identification of a mutation combined with embryo's HLA typing, to obtain, at birth, stem cells for therapeutic purposes, and on the other hand, to avoid transmission of late onset diseases without having to test the at-risk parent. Other applications are practiced worldwide but are not allowed in our country, such as social sexing. Technological developments can enable more complex diagnosis, research of several diseases or other genetic traits. It may be useful, for example, to use this possibility to add screening for Down's syndrome at any PDG in older women, when the risk is high. Other objectives were considered but presenting difficulties in their application, not only for regulatory and technical reasons, but also from an ethical point of view. PMID:23085048
Gosset, P
Preimplantation genetic diagnosis, an alternative to conventional prenatal diagnosis of the hemoglobinopathies.
Prenatal diagnosis (PND) and preimplantation genetic diagnosis (PGD) both represent highly important reproductive choices for couples with a high risk of transmitting a severe disease, such as a severe hemoglobinopathy. Conventional PND for hemoglobinopathies based on molecular analysis of trophoblast or amniocyte DNA has been applied for around 30�years, but the major disadvantages with this approach include 'invasive' fetal sampling, and the potential involvement of pregnancy termination when affected. In comparison, the major advantage of PGD over conventional PND is that it supports the initiation of unaffected pregnancies, avoiding the need to terminate affected pregnancies. However, it is a multistep technically demanding procedure requiring the close collaboration of experts from several fields. PGD is also limited by the need to involve assisted reproduction, even in couples without fertility problems. Furthermore, even for fertile couples, pregnancy rates rarely surpass 30-35%. Both PND and PGD have advantages and drawbacks. Before embarking on either procedure, couples should be carefully counseled by experts so that they can select the option most appropriate for them. Finally, whatever their choice, it is paramount that both prenatal and PGD be applied with the highest standards of clinical, laboratory, and ethical practice. PMID:23551498
Traeger-Synodinos, J
Impact of preimplantation genetic diagnosis on IVF outcome in implantation failure patients
Implantation failure (IF) is defined as three or more failed IVF attempts, and preimplantation genetic diagnosis (PGD) is being used in these patients to improve IVF outcome. PGD was performed in 49 implantation failure patients with a mean number of 4.2 � 1.6 previous IVF failures, and in nine fertile controls. Fluorescence in-situ hybridization (FISH) on blastomeres from biopsied day
T Pehlivan; C Rubio; L Rodrigo; J Romero; J Remohi; C Sim�n; A Pellicer
Peutz-Jeghers syndrome and family planning: the attitude towards prenatal diagnosis and pre-implantation genetic diagnosis
Peutz�Jeghers syndrome (PJS) is a hereditary disorder caused by LKB1 gene mutations, and is associated with considerable morbidity and decreased life expectancy. This study was conducted to assess the attitude of PJS patients towards family planning, prenatal diagnosis (PND) and pregnancy termination, and pre-implantation genetic diagnosis (PGD). In a cross-sectional study, 61 adult PJS patients were asked to complete a questionnaire concerning genetic testing, family planning, PND and PGD. The questionnaire was completed by 52 patients (85% response rate, 44% males) with a median age of 44 (range 18�74) years. A total of 37 (71%) respondents had undergone genetic testing. In all, 24 respondents (46%, 75% males) had children. A total of 15 (29%) respondents reported that their diagnosis of PJS had influenced their decisions regarding family planning, including 10 patients (19%, 9/10 females) who did not want to have children because of their disease. Termination of pregnancy after PND in case of a foetus with PJS was considered �acceptable' for 15% of the respondents, whereas 52% considered PGD acceptable. In conclusion, the diagnosis of PJS influences the decisions regarding family planning in one third of PJS patients, especially in women. Most patients have a negative attitude towards pregnancy termination after PND, while PGD in case of PJS is judged more acceptable. These results emphasise the importance of discussing aspects regarding family planning with PJS patients, including PND and PGD.
van Lier, Margot G F; Korsse, Susanne E; Mathus-Vliegen, Elisabeth M H; Kuipers, Ernst J; van den Ouweland, Ans M W; Vanheusden, Kathleen; van Leerdam, Monique E; Wagner, Anja
The uptake and outcome of prenatal and pre-implantation genetic diagnosis for Huntington's disease in the Netherlands (1998-2008).
We aimed to study reproductive behaviour of couples opting for prenatal diagnosis (PND) and pre-implantation genetic diagnosis (PGD) for Huntington's disease (HD). In the Netherlands, exclusion PND is available for persons at 50% risk, whereas exclusion PGD is not allowed. All 162 couples who underwent PND or PGD for HD between 1998 and 2008 and referrals for exclusion PGD to Belgium were included. Couples' reproductive information was collected until December 2010; 132 couples (81.5%) underwent PND in 262 pregnancies, 54 (33.3%) started PGD, and 25 used both. Sixteen percent of PND couples used exclusion PND and 6% used exclusion PGD. The outcomes were 76.5% of PND couples delivered ?1 unaffected child(ren) after PND, and 44.4% of PGD couples delivered ?1 PGD child(ren) (mean 2.5?cycles/couple). Couples opting for PGD secondarily (after a previous pregnancy) had more frequently terminated a pregnancy for HD (87.0%) compared with couples secondarily opting for PND (55.2%; p?=?0.015). At-risk or HD expansion carrier males were underrepresented in the group of couples primarily opting for PGD (25%) and overrepresented in the secondary PGD group (64%). We conclude that couples reconsider their choices in every subsequent pregnancy based on their previous experience, personal beliefs and the gender of the at-risk partner. PMID:23350580
van Rij, M C; de Koning Gans, P A M; van Belzen, M J; Roos, R A C; Geraedts, J P M; De Rademaeker, M; Bijlsma, E K; de Die-Smulders, C E M
Preimplantation genetic diagnosis for Charcot-Marie-Tooth disease
Objective Preimplantation genetic diagnosis (PGD) is an assisted reproductive technique for couples carrying genetic risks. Charcot-Marie-Tooth (CMT) disease is the most common hereditary neuropathy, with a prevalence rate of 1/2,500. In this study, we report on our experience with PGD cycles performed for CMT types 1A and 2F. Methods Before clinical PGD, we assessed the amplification rate and allele drop-out (ADO) rate of multiplex fluorescent polymerase chain reaction (PCR) followed by fragment analysis or sequencing using single lymphocytes. We performed six cycles of PGD for CMT1A and one cycle for CMT2F. Results Two duplex and two triplex protocols were developed according to the available markers for each CMT1A couple. Depending on the PCR protocols, the amplification rates and ADO rates ranged from 90.0% to 98.3% and 0.0% to 11.1%, respectively. For CMT2F, the amplification rates and ADO rates were 93.3% and 4.8%, respectively. In case of CMT1A, 60 out of 63 embryos (95.2%) were diagnosed and 13 out of 21 unaffected embryos were transferred in five cycles. Two pregnancies were achieved and three babies were delivered without any complications. In the case of CMT2F, a total of eight embryos were analyzed and diagnosed. Seven embryos were diagnosed as unaffected and four embryos were transferred, resulting in a twin pregnancy. Two healthy babies were delivered. Conclusion This is the first report of successful pregnancy and delivery after specific PGD for CMT disease in Korea. Our PGD procedure could provide healthy babies to couples with a high risk of transmitting genetic diseases.
Lee, Hyoung-Song; Kim, Min Jee; Ko, Duck Sung; Jeon, Eun Jin; Kim, Jin Young
Ethical considerations on preimplantation genetic diagnosis for HLA typing to match a future child as a donor of haematopoietic stem cells to a sibling
Recently, several requests were made by couples with an affected child who wanted preimplantation genetic diagnosis (PGD) to select embryos in the hope of conceiving an HLA identical donor sibling. This article considers the ethical arguments for and against the application of PGD for this goal. Only embryos HLA matched with an existing sibling in need of a compatible donor
G. Pennings; R. Schots; I. Liebaers
Human embryos as boundary objects? Some reflections on the biomedical worlds of embryonic stem cells and pre-implantation genetic diagnosis
In this paper we offer some reflections on embryos in the biomedical worlds of embryonic stem cells (ESC) and pre-implantation genetic diagnosis (PGD). We draw upon two ethnographic studies of the social practices of PGD and embryonic stem cell science to examine the notion of boundary objects as an approach for understanding the social construction of embryos. We analyze the
Clare Williams; Steven P. Wainwright; Kathryn Ehrich; Mike Michael
�Saviour Siblings�? The Distinction between PGD with HLA Tissue Typing and Preimplantation HLA Tissue Typing
One of the more controversial uses of preimplantation genetic diagnosis (PGD) involves selecting embryos with a specific tissue\\u000a type so that the child to be born can act as a donor to an existing sibling who requires a haematopoietic stem cell transplant.\\u000a PGD with HLA tissue typing is used to select embryos that are free of a familial genetic disease
Crystal K. Liu
Preimplantation Genetic Diagnosis in Canada: A Survey of Canadian IVF Units
Objective: To determine the current practice patterns of preimplantation genetic diagnosis (PGD) in Canada related to genetic counselling, embryo biopsy, and cytogenetic and molecular analyses. Methods: An Internet survey was constructed and administered following Dillman's tailored design method. The contact information for medical directors of all 28 Canadian IVF units was provided by Assisted Human Reproduction Canada. Results: Seventeen of
Kathy N. Speechley; Jeff Nisker
A retrospective study of paediatric health and development following pre-implantation genetic diagnosis and screening
Pre-implantation genetic diagnosis and screening (PGD and PGS) are treatments for patients that have (or are carriers of) an inherited genetic disorder, or who have had a history of miscarriage, problems with embryo implantation, etc. Often conducted alongside assisted reproductive technologies (ART), a number of embryos are produced, and the DNA and chromosomes of each are tested for various disorders
Mark Olive; Alison Lashwood; Tony Solomonides
First successful application of preimplantation genetic diagnosis and haplotyping for congenital hyperinsulinism
Congenital hyperinsulinism is the most common cause of persistent hypoglycaemia in infancy. Early surgical intervention is usually required to prevent brain damage. The prevention of the transmission to the offspring is important in families carrying the mutated gene. Preimplantation genetic diagnosis (PGD) is an early genetic testing procedure for couples at risk of transmitting inherited diseases. A 36-year-old Saudi woman
Wafa Qubbaj; Abdulrahman Al-Swaid; Saad Al-Hassan; Khalid Awartani; Hesham Deek; Serdar Coskun
The Case for a Parental Duty to Use Preimplantation Genetic Diagnosis for Medical Benefit
This article explores the possibility that there is a parental duty to use preimplantation genetic diagnosis (PGD) for the medical benefit of future children. Using one genetic disorder as a paradigmatic example, we find that such a duty can be supported in some situations on both ethical and legal grounds. Our analysis shows that an ethical case in favor of
Janet Malek; Judith Daar
Preimplantation genetic diagnosis: Analysis of gene expression, nuclear DNA and cytoplasmic DNA
Preimplantation genetic diagnosis (PGD) following in vitro fertilization (IVF) offers couples at risk for transmitting genetic disorders the opportunity to identify affected embryos prior to replacement. In particular, embryo gender determination permits screening for X-linked diseases of unknown etiology. Analysis of embryos can be performed by polymerase chain reaction (PCR) amplification of material obtained by micromanipulation. This approach provides an
Nury Miranda Steuerwald
Dealing with uncertainties: ethics of prenatal diagnosis and preimplantation genetic diagnosis to prevent mitochondrial disorders.
This paper aims to address the ethical issues regarding prenatal diagnosis and preimplantation genetic diagnosis (PGD) of mitochondrial disorders. Owing to the absence of effective treatment, the prevention of the transmission of mitochondrial disorders is considered to be of key importance. The characteristics of mtDNA, such as heteroplasmy and the genetic bottleneck, make it difficult to estimate recurrence risks correctly and to provide an accurate prognosis for many mtDNA mutations. A limited number of mtDNA mutations allow reliable predictions, though results in the 'grey zone' are problematic. Both prenatal diagnosis and PGD for mtDNA disorders are complicated by the interpretation of the test results. As a consequence, these applications confront both clinical practice and society at large with several ethical questions and issues for further debate, among which the acceptability of suboptimal genetic testing, the value and research use of embryos, the evaluation of late abortion, the ethics of PGD for disorders with an incomplete penetrance and variable expression, the possible transfer of embryos with residual health risks, the acceptability of risks and drawbacks of genetic reproductive technology in general, and the scope and limits of reproductive autonomy and professional responsibility. PMID:18056133
Bredenoord, A L; Pennings, G; Smeets, H J; de Wert, G
Aberrant epigenetic modification in murine brain tissues of offspring from preimplantation genetic diagnosis blastomere biopsies.
Preimplantation genetic diagnosis (PGD) has been prevalent in the field of assisted reproductive technology, yet the long-term risks of PGD to offspring remain unknown. In the present study, the early development of PGD embryos, postimplantation characteristics, and birth rate following PGD were determined. Moreover, the behavior of the offspring conceived from the biopsied embryos was evaluated with the Morris water maze and pole climbing tests. Finally, the epigenetic modification of the global genome and methylation patterns for the H19, Igf2, and Snrpn imprinted genes were identified. The results indicated a significant delay in the blastocoel formation of PGD embryos and a decrease in the implantation ability of these embryos, which was related to the decreased number of cells in the PGD blastocysts. The PGD mice spent more time on both the nontrained quadrant of the water maze and climbing down the pole. Furthermore, the 5-hydroxymethylcytosine content in the brain tissues of PGD mice was significantly increased, but no difference was found in 5-methylcytosine content. The differentially methylated regions of H19/Igf2 exhibited decreased methylation patterns, but that of Snrpn was normal, compared to the control group. Quantitative RT-PCR indicated that Igf2 mRNA expression was significantly decreased but that H19 and Snrpn mRNAs were expressed normally. In conclusion, blastomere biopsies in PGD procedures carry potential risks to embryo development and the behavior of resulting offspring; these risks may arise from aberrant epigenetic modification and methylation patterns in brain tissues. Further studies are needed to better understand the risks associated with PGD. PMID:24089199
Zhao, Hong-Cui; Zhao, Yue; Li, Min; Yan, Jie; Li, Li; Li, Rong; Liu, Ping; Yu, Yang; Qiao, Jie
[Genetic cancer syndromes and reproductive choice: dialogue between parents and politicians on preimplantation genetic diagnosis].
Genetic cancer syndromes have identical clinical severity, limited therapeutic options, reduced life expectancy, and risks of genetic transmission, as do other genetic or congenital diseases for which prenatal genetic diagnosis or preimplantation genetic diagnosis (PGD) is allowed in the Netherlands. That was implied in the certification of one Dutch PGD centre at Maastricht University Hospital by the Dutch Ministry of Health, Welfare and Sport in 2003. A report by the Health Council of the Netherlands in 2006 confirmed this view with scientific and ethical evaluation. However, in 2006 the State Secretary for Health strongly objected to PGD for cancer, and disease risks of 50-100% for gene carriers, i.e. for highly, but not always fully penetrant genes. In 2006, the Maastricht centre discontinued PGD for cancer and couples were referred to other countries; prenatal genetic diagnosis remained available, however. On 26 May 2008, the present State Secretary proposed to parliament that the Health Council of the Netherlands report from 2006 be followed. This once again clashed with the fears of some Christian parties for a slippery slope and embryo selection for 'only a risk and not certainty of disease'. Yet no firm evidence for the existence of such a slope has been found. The Dutch framework for handling the ethical and medical evaluation of new reproductive and genetic technologies by the Health Council of the Netherlands Advisory Committees, professional and patient organisations, and the Ministry, has functioned for over 30 years without leading to any wrongdoing. There is no actual need for a new government body to license genetic tests on a case-by-case or per disease basis. PMID:18681358
Niermeijer, M F; de Die-Smulders, C E M; Page-Christiaens, G C M L; de Wert, G M W R
[Extending preimplantation genetic diagnosis to HLA typing: the French exception].
Umut-Talha, a "sibling savior", was born on 26 January 2011 at Becl�re Hospital after embryo selection at the Paris preimplantation genetic diagnosis (PGD) center. His birth revived the controversy over "double PGD". This procedure, authorized in France since 2006, allows couples who already have a child with a serious, incurable genetic disease, to opt for PGD in order to select a healthy embryo that is HLA-matched to the affected sibling and who may thus serve as an ombilical cord blood donor. The procedure is particularly complex and the baby take-home rate is still very low. Double PGD is strictly regulated in France, and candidate couples must first receive individual authorization from the Biomedicine Agency. In our experience, these couples have a strong desire to have children, as reflected by the large number of prior spontaneous pregnancies (25% of couples). Likewise, most of these couples request embryo transfer even when there is no HLA-matched embryo, which accounts for more than half of embryo transfers. The controversy surrounding this practice has flared up again in recent weeks, over the concepts of "designer babies" and "double savior siblings" (the baby is selected to be free of the hereditary disease, and may also serve as a stem cell donor for the affected sibling). PMID:22375367
Steffann, Julie; Frydman, Nelly; Burlet, Philippe; Gigarel, Nadine; Hesters, Laetitia; Kerbrat, Violaine; Lamazou, Fr�d�ric; Munnich, Arnold; Frydman, Ren�
Choosing disability: preimplantation genetic diagnosis and negative enhancement.
This article examines the unusual circumstance of what the author has tentatively termed "negative enhancement". This term is used to describe those instances where individuals seek to use preimplantation genetic diagnosis (PGD) to achieve outcomes that, commonly, are socially not preferred. In a recent survey by the Genetics and Public Policy Centre, it was found that 3% of IVF-PGD clinics in the United States reported having provided PGD to couples who seek to select an embryo for the presence of a particular disease or disability, such as deafness, in order that the child share the characteristic with the parents. The idea of "negative enhancement" is, therefore, both a paradox and a useful means to describe the hidden assumptions behind claims that enhancement technologies can only lead us in one direction -- towards a race of blond, blue-eyed, able-bodied, intellectually magnificent and athletically superior beings. In Australia there does appear to be a consensus that PGD should only be used to select against serious disability. This inevitably raises the question of how we define disability and who is best placed to make decisions about the kind of kin we want to create. PMID:17902492
Karpin, Isabel
The identification and avoidance of disease susceptibility in embryos is the most common goal of preimplantation genetic diagnosis (PGD). Most jurisdictions that accept but regulate the availability of PGD restrict it to what are characterized as 'serious' conditions. Line-drawing around seriousness is not determined solely by the identification of a genetic mutation. Other factors seen to be relevant include: impact on health or severity of symptoms; degree of penetrance (probability of genotype being expressed as a genetic disorder); potential for therapy; rate of progression; heritability; and age of onset. In the original applications of PGD, most, if not all of these factors were seen as necessary but none was seen as sufficient for determining whether a genetic condition was labelled 'serious'. This, however, is changing as impact on health or severity of symptoms is coming to eclipse the other considerations. This paper investigates how age of onset (primarily in the context of the United Kingdom (UK)) has become considerably less significant as a criterion for determining ethically acceptable applications of PGD. Having moved off the threshold of permitting PGD testing for only fatal (or seriously debilitating), early-onset diseases, I will investigate reasons for why age of onset will not do any work to discriminate between which adult-onset diseases should be considered serious or not. First I will explain the rationale underpinning age of onset as a factor to be weighed in making determinations of seriousness. Next I will challenge the view that later-onset conditions are less serious for being later than earlier-onset conditions. The final section of the paper will discuss some of the broader disability concerns at stake in limiting access to PGD based upon determinations of the 'seriousness' of genetic conditions. Instead of advocating a return to limiting PGD to only early-onset conditions, I conclude that the whole enterprise of trying to draw lines of what is to count as a 'serious' condition is itself problematic and in certain ways morally misleading. PMID:18979183
Krahn, Timothy
Effect of infertility, maternal age, and number of previous miscarriages on the outcome of preimplantation genetic diagnosis for idiopathic recurrent pregnancy loss
Objective: To determine whether preimplantation genetic diagnosis (PGD) would decrease spontaneous abortion rates in patients with idiopathic recurrent pregnancy loss (RPL). Design: Controlled clinical study. Setting: IVF center and PGD reference laboratory. Patient(s): Patients with RPL with no known etiology. Intervention(s): Preimplantation genetic diagnosis by fluorescence in situ hybridization analyzing nine chromo- somes. Main Outcome Measure(s): The spontaneous abortion rate
John G. Garrisi; Pere Colls; Kathleen M. Ferry; Xhezong Zheng; Margarett G. Garrisi; Santiago Munn�
Polymorphism at the G6pd and 6Pgd loci in Drosophila melanogaster . IV. Genetic factors modifying enzyme activity
Different homozygous lines of similar genotype with respect to G6pd and 6Pgd were shown to have different enzyme activities for G6PD and 6PGD. Crosses between high and low lines suggested that there were modifying genes present on the autosomes, while others were probably located on the X chromosome. Allelic variation within each electrophoretic class of G6pd and 6Pgd might, however,
R. Bijlsmal
The future (r)evolution of preimplantation genetic diagnosis/human leukocyte antigen testing: ethical reflections.
There has been increasing support for combining preimplantation genetic diagnosis (PGD) for specific diseases with a test for human leukocyte antigens (HLA) because the generation of HLA-matched umbilical cord blood cells may save the life of a diseased sibling. To date, this procedure has taken place in the context of conceiving another child--PGD/HLA testing type 1. However, it may well become possible to perform PGD/HLA testing outside this context, that is, to select matched embryos from which embryonic stem cells could be derived and used in cell therapy--PGD/HLA testing type 2. A proactive ethical analysis is needed and is presented in this article. Although PGD/HLA testing type 1 can be morally justified, the risks, pitfalls, and practical limitations of this procedure make it necessary to develop alternative strategies. PGD/HLA testing type 2 may provide an alternative strategy. From an ethical point of view, the controversial issue is that this procedure creates embryos purely for instrumental use. However, given the dominant view that the preimplantation embryo has only limited moral value, this alternative may be as morally justified as PGD/HLA testing type 1. PMID:17525240
de Wert, Guido; Liebaers, Inge; Van de Velde, Hilde
Complexities in reproductive choice: medical professionals' attitudes to and experiences of pre-implantation genetic diagnosis.
Studies have been made on attitudes to and experiences of women and men who have undergone pre-implantation genetic diagnosis (PGD), or who are regarded as potential users of this diagnostic method. Few studies have been conducted regarding the attitudes to and experiences of medical professionals as regards PGD. This paper reports on findings from such a qualitative study in which 18 semi-structured interviews were performed with geneticists and gynaecologists in Italy, Sweden and the UK. Interviewees emphasized, among other things, the importance of choice provision. Interviewees also told stories that indicated the many ways through which choice was feared to be hampered - or was hampered. A similar emphasis on the importance of PGD as one more alternative to choose between, for 'high-risk' couples, is not found in studies on the experiences, attitudes and views of potential, or actual, users of PGD. PMID:17786649
Zeiler, Kristin
Hereditary breast and ovarian cancer and reproduction: an observational study on the suitability of preimplantation genetic diagnosis for both asymptomatic carriers and breast cancer survivors.
Preimplantation genetic diagnosis (PGD) is a reproductive option for BRCA1/2 mutation carriers wishing to avoid transmission of the predisposition for hereditary breast and ovarian cancer (HBOC) to their offspring. Embryos obtained by in vitro fertilisation (IVF/ICSI) are tested for the presence of the mutation. Only BRCA-negative embryos are transferred into the uterus. The suitability and outcome of PGD for HBOC are evaluated�in an observational cohort study on treatments carried out in two of Western-Europe's largest PGD centres from 2006 until 2012. Male carriers, asymptomatic female carriers and breast cancer survivors were eligible. If available, PGD on embryos cryopreserved before chemotherapy was possible. Generic PGD-PCR tests were developed based on haplotyping, if necessary combined with mutation detection. 70 Couples underwent PGD for BRCA1/2. 42/71 carriers (59.2�%) were female, six (14.3�%) of whom have had breast cancer prior to PGD. In total, 145 PGD cycles were performed. 720 embryos were tested, identifying 294 (40.8�%) as BRCA-negative. Of fresh IVF/PGD cycles, 23.9�% resulted in a clinical pregnancy. Three cycles involved PGD on embryos cryopreserved before chemotherapy; two of these women delivered a healthy child. Overall, 38 children were liveborn. Two BRCA1 carriers were diagnosed with breast cancer shortly after PGD treatment, despite negative screening prior to PGD. PGD for HBOC proved to be suitable, yielding good pregnancy rates for asymptomatic carriers as well as breast cancer survivors. Because of two cases of breast cancer shortly after treatment, maternal safety of IVF(PGD) in female carriers needs further evaluation. PMID:24748567
Derks-Smeets, Inge A P; de Die-Smulders, Christine E M; Mackens, Shari; van Golde, Ron; Paulussen, Aimee D; Dreesen, Jos; Tournaye, Herman; Verdyck, Pieter; Tjan-Heijnen, Vivianne C G; Meijer-Hoogeveen, Madelon; De Greve, Jacques; Geraedts, Joep; De Rycke, Martine; Bonduelle, Maryse; Verpoest, Willem M
An evaluation of PGD in clinical genetic services through 3 years application for prevention of beta-thalassaemia major and sickle cell thalassaemia
PGD represents an alternative within prenatal diagnosis services, which avoids terminating affected on-going pregnancies. In Greece, prevention programmes for haemoglobinopathies, including the option of prenatal diagnosis, are well established. Following optimization of a single-cell genotyping strategy (designed to be applicable for the majority of b-thalassaemia major or sickle thalassaemia genotype interactions) along with close collaboration with an IVF unit, we
Joanne Traeger-Synodinos; Christina Vrettou; Giles Palmer; Maria Tzetis; Minas Mastrominas; Stephen Davies; Emmanuel Kanavakis
Ethical Concerns to the use of Pre-implantation Genetic Diagnosis in the Gulf Cooperative Council States
Assisted reproductive technology (ART) makes pre-implantation genetic diagnosis (PGD) possible, allowing embryos to be screened genetically before placement in the uterus, by analyzing the DNA from a single cell after amplification by polymerase chain reaction and\\/or the use of fluorescence in situ hybridization (FISH) technique. However, many objections have been raised against genetic screening of embryos, giving the practice an
Hamza Ali Eskandarani
Medical and social perspectives of PGD for single gene disorders and human leukocyte antigen typing
Preimplantation genetic diagnosis (PGD) for single gene disorders combined with human leukocyte antigen (HLA) typing has recently emerged as a therapeutic tool. For couples who are at risk of passing on a genetic disease to their offspring, preimplantation embryos can be selected according to their genetic status as well as a possible HLA matching with the affected sibling. Stem cells
Semra Kahraman; Necati Findikli; Guvenc Karliklaya; Semra Sertyel; Huseyin Karadayi; Yaman Saglam; Francesco Fiorentino
Preimplantation genetic diagnosis reduces pregnancy loss in women aged 35 years and older with a history of recurrent miscarriages
Objective: To determine whether preimplantation genetic diagnosis (PGD) and transfer of euploid embryos would decrease spontaneous abortion rates in recurrent miscarriage (RM) patients. Design: Controlled clinical study. Setting: In vitro fertilization centers and PGD reference laboratory. Patient(s): Recurrent-miscarriage patients with three or more prior lost pregnancies with no known etiology. Intervention(s): Biopsy of a single blastomere from each day 3
Santiago Munn�; Serena Chen; Jill Fischer; Pere Colls; Xuezong Zheng; John Stevens; Tomas Escudero; Maria Oter; Joe Leigh Simpson; Jacques Cohen
On new reproductive technologies and family ethics: Pre-implantation genetic diagnosis for sibling donor in Israel and Germany
This paper discusses the policy debate and ethical discussion surrounding pre-implantation genetic diagnosis (PGD) for sibling donor (SD) in Germany and Israel. Based on an analysis of the regulations and ethical discourse concerning a unique form of new reproductive technology (NRT)�PGD for SD�we complement the scholarly discussion of NRTs in these countries, by pointing to an explanatory factor that has
Yael Hashiloni-Dolev; Shiri Shkedi
PGD for all cystic fibrosis carrier couples: novel strategy for preventive medicine and cost analysis
Over 1000 children affected with cystic fibrosis (CF) are born annually in the USA. Since IVF with preimplantation genetic diagnosis (PGD) is an alternative to raising a sick child or to aborting an affected fetus, a cost�benefit analysis was performed for a national IVF�PGD program for preventing CF. The amount spent to deliver healthy children for all CF carrier-couples by
I. Tur-Kaspa; G. Aljadeff; S. Rechitsky; H. E. Grotjan; Y. Verlinsky
Moral attitudes and beliefs among couples pursuing PGD for sex selection
This article reports the results from a study of couples participating in a research protocol in which IVF\\/preimplantation genetic diagnosis (PGD) was available for non-medical sex selection. The study sought to characterize the moral attitudes and beliefs of couples actively pursuing IVF\\/PGD solely for purposes related to sex selection. Eighteen couples participated in ethnographic interviews from November 2005 to April
Richard R. Sharp; Michelle L. McGowan; Jonathan A. Verma; David C. Landy; Sallie McAdoo; Sandra A. Carson; Joe Leigh Simpson; Laurence B. McCullough
Preimplantation genetic diagnosis in Germany: ethical responsibility and law
Preimplantation diagnosis (PGD) can be judged as early or brought forward prenatal diagnosis and brings up the ethical question in Germany whether potential selection of embryos and intentional killing of a human conceptus, showing a defect not or almost not compatible with life, is reconcilable with human dignity. Whereas prenatal diagnosis and its consequences are socially accepted in Germany, PGD
W K�pker; G Huber; M Ludwig; K Diedrich
The use of preimplantation genetic diagnosis in sex selection for family balancing in India
This paper describes the use of preimplantation genetic diagnosis (PGD) in sexing embryos for family balancing in a private IVF clinic in India from April 1999 to April 2001. Embryos were biopsied and analysed on day 3, cultured in sequential media and then transferred on day 4 or day 5 after morphological selection of the best embryos. From a total
A Malpani; D Modi
Will preimplantation genetic diagnosis assist patients with a poor prognosis to achieve pregnancy?
ductive techniques may be related to the high rates of chromo- somal disorders which are routinely observed in oocytes 3 To whom correspondence should be addressed obtained from stimulated cycles or during early cleavage events PGD (preimplantation genetic diagnosis) of aneuploidy for (Plachot and Mandelbaum, 1990; Pellestor, 1991; Delhanty and chromosomes X, Y, 13, 18 and 21 was carried out
L. Gianaroli; M. C. Magli; S. Munne; A. Fiorentino; N. Montanaro; A. P. Ferraretti
A clinical perspective on ethical arguments around prenatal diagnosis and preimplantation genetic diagnosis for later onset inherited cancer predispositions
Prenatal diagnosis (PND) and preimplantation genetic diagnosis (PGD) for later onset and\\/or reduced penetrance inherited cancer\\u000a predispositions, e.g. familial adenomatous polyposis, hereditary non-polyposis colorectal cancer\\/Lynch syndrome and hereditary\\u000a breast and ovarian cancer, raise a number of ethical issues. Some of these are the same as for conditions which present early\\u000a in childhood, are fully penetrant and for which no\\/limited treatment
Tara Clancy
An analysis of US fertility centre educational materials suggests that informed consent for preimplantation genetic diagnosis may be inadequate.
The use of preimplantation genetic diagnosis (PGD) has expanded both in number and scope over the past 2 decades. Initially carried out to avoid the birth of children with severe genetic disease, PGD is now used for a variety of medical and non-medical purposes. While some human studies have concluded that PGD is safe, animal studies and a recent human study suggest that the embryo biopsy procedure may result in neurological problems for the offspring. Given that the long-term safety of PGD has not been clearly established in humans, this study sought to determine how PGD safety is presented to prospective patients by means of a detailed website analysis. The websites of 262 US fertility centres performing PGD were analysed and comments about safety and risk were catalogued. Results of the analysis demonstrated that 78.2% of centre websites did not mention safety or risk of PGD at all. Of the 21.8% of centres that did contain safety or risk information about PGD, 28.1% included statements highlighting the potential risks, 38.6% presented information touting the procedure as safe and 33.3% included statements highlighting potential risks and the overall safety of the procedure. Thus, 86.6% of PGD-performing centres state that PGD is safe and/or fail to disclose any risks on their websites despite the fact that the impact of the procedure on the long-term health of offspring is unproven. This lack of disclosure suggests that informed consent is inadequate; this study examines numerous factors that are likely to inhibit comprehensive discussions of safety. PMID:22493184
LaBonte, Michelle Lynne
[The Cagliari (Italy) Court authorizes the preimplantation genetic diagnosis].
Today, preimplantation genetic diagnosis (PGD) has been greatly accepted within the framework of positive law of many European countries. Nevertheless, in other countries, such as Italy, it is forbidden by law. The ruling of the Civil Court of Cagliari which has authorized its use to a Sardinian couple, has opened, in this way, a small crack to be able to asses possible modifications to the Italian regulation on this matter. This article analyses the ruling of the Civil Court of Cagliari (Italy) from an ethical and legal perspective. The criteria which is used to analyse the legitimacy or illegitimacy of the practice of PGD is analysed. That is, on reasons which could justify or not the transfer of embryos in vitro to the woman. With this objective in mind, the Italian and Spanish normative models which regulates this controversial subject are looked at. As a conclusion, a critical evaluation of the arguments presented is made. PMID:18330104
Jorqui Azofra, Mar�a
The regulation of preimplantation genetic diagnosis (PGD)intheNetherlandsandtheUK:acomparativestudy of the regulatory frameworks and outcomes for PGD
Developments in biotechnology present difficult social and ethical challenges that need to be resolved by regulators among others. One crucial problem for regulators of new technologies is to ensure that regulation is both clear and sufficiently flexible to respond to new developments. This is particularly difficult to achieve in contentious fields such as medical biotechnology. In the European Union there
Eva C A Asscher
Current status of preimplantation diagnosis for single gene disorders
Preimplantation genetic diagnosis (PGD) has become an established procedure for avoiding the birth of affected children with single gene disorders. PGD is performed through polar body or blastomere biopsy, which has no deleterious effect on pre- and post-implantation development. This review describes the most recent developments and current changes in the spectrum of conditions for which PGD has been applied.
Yury Verlinsky; Anver Kuliev
ESHRE Task Force on Ethics and Law22: Preimplantation Genetic Diagnosis�.
This Task Force document discusses some relatively unexplored ethical issues involved in preimplantation genetic diagnosis (PGD). The document starts from the wide consensus that PGD is ethically acceptable if aimed at helping at-risk couples to avoid having a child with a serious disorder. However, if understood as a limit to acceptable indications for PGD, this 'medical model' may turn out too restrictive. The document discusses a range of possible requests for PGD that for different reasons fall outwith the accepted model and argues that instead of rejecting those requests out of hand, they need to be independently assessed in the light of ethical criteria. Whereas, for instance, there is no good reason for rejecting PGD in order to avoid health problems in a third generation (where the second generation would be healthy but faced with burdensome reproductive choices if wanting to have children), using PGD to make sure that one's child will have the same disorder or handicap as its parents, is ethically unacceptable. PMID:24927929
De Wert, G; Dondorp, W; Shenfield, F; Devroey, P; Tarlatzis, B; Barri, P; Diedrich, K; Provoost, V; Pennings, G
A qualitative inquiry of the financial concerns of couples opting to use preimplantation genetic diagnosis to prevent the transmission of known genetic disorders.
Preimplantation genetic diagnosis (PGD) is an innovative prenatal testing option because the determination of whether a genetic disorder or chromosomal abnormality is evident occurs prior to pregnancy. However, PGD is not covered financially under the majority of private and public health insurance institutions in the United States, leaving couples to decide whether PGD is financially feasible. The aim of this qualitative study was to understand the role of finances in the decision-making process among couples who were actively considering PGD. In-depth, semi-structured interviews were completed with 18 genetic high-risk couples (36 individual partners). Grounded theory guided the analysis, whereby three themes emerged: 1) Cost is salient, 2) Emotions surrounding affordability, and 3) Financial burden and sacrifice. Ultimately, couples determined that the opportunity to avoid passing on a genetic disorder to a future child was paramount to the cost of PGD, but expressed financial concerns and recognized financial access as a major barrier to PGD utilization. PMID:23949612
Drazba, Kathryn T; Kelley, Michele A; Hershberger, Patricia E
More than 10 years after the first 'savior siblings': parental experiences surrounding preimplantation genetic diagnosis.
Preimplantation genetic diagnosis (PGD) to create a healthy donor for a sibling's hematopoetic stem cell transplantation for a child with Fanconi Anemia (FA) was first reported in 2001. Yet we know little about the experiences of parents who have encountered decision making surrounding PGD and human leukocyte antigen (HLA)-typing. The first aim of this study was to understand parents' awareness, perceptions and beliefs about reproductive decision-making including emotional, cognitive, moral dimensions as well as regret surrounding the use of this technology. The second aim was to describe the experiences and rationale of parents of children with a single gene disorder regarding the factors that influenced their decision making surrounding the use of natural pregnancy and/or PGD and HLA-typing. Parents from two national FA support networks in the US and Canada responded to an emailed survey about reproductive decision making and outcomes surrounding natural pregnancy and PGD and HLA-typing. Descriptive statistics and Pearson's Chi-Square tests were used to describe and compare data. Our results indicate that the most important factors in the PGD decision making process were the health of the child and cognitive appraisals followed by emotional responses and then moral judgments. A significant difference was noted in parents considering natural pregnancy before and after 2001 (p = 0.01). Unexpected findings were that less than 35 % of parents were offered PGD by any health care professional and only 70 % were aware PGD with HLA-typing was a reproductive option. Our research suggests that the option of PGD and HLA-typing may influence parents' reproductive decision making choices. PMID:23624741
Zierhut, Heather; MacMillan, Margaret L; Wagner, John E; Bartels, Dianne M
A clinical perspective on ethical arguments around prenatal diagnosis and preimplantation genetic diagnosis for later onset inherited cancer predispositions.
Prenatal diagnosis (PND) and preimplantation genetic diagnosis (PGD) for later onset and/or reduced penetrance inherited cancer predispositions, e.g. familial adenomatous polyposis, hereditary non-polyposis colorectal cancer/Lynch syndrome and hereditary breast and ovarian cancer, raise a number of ethical issues. Some of these are the same as for conditions which present early in childhood, are fully penetrant and for which no/limited treatment options are possible; others relate to whether reduced penetrance and/or the availability of treatment mean that these are not serious (enough) conditions to warrant tests prior to/during pregnancy or to justify termination of pregnancy. However, attempts to reach a consensus on what counts as a serious (enough) condition in the context of PND and PGD have been unsuccessful. Such a definition may anyway be unhelpful if it cannot also take into account, for example, the woman's/couple's awareness and experience of the condition and the impact of the condition on affected individuals and their families. Individuals affected by, or at high risk of, later onset and/or reduced penetrance inherited cancer predispositions are generally supportive of access to PND and PGD for their own conditions, even if they would not consider using it themselves. Professionals working in clinical cancer genetics need to be prepared to discuss PND and PGD with this group of patients. PMID:19644768
Clancy, Tara
Decisions and ethical issues among BRCA carriers and the use of preimplantation genetic diagnosis.
The lifetime risks for both breast and ovarian cancer for BRCA mutation carriers far exceeds the general population risk of 13% for breast cancer and 1.4% for ovarian cancer. BRCA carriers have unique and medically complicated decisions to make regarding their cancer treatment or risk reduction. As BRCA testing becomes increasingly common among unaffected individuals in families with a previously documented BRCA mutation, there are a growing number of individuals with unique psychosocial needs and concerns. This review paper describes the BRCA 1/2 population, discusses preimplantation genetic diagnosis (PGD), and describes the decisions and ethical issues related to PGD among the BRCA 1/ 2 population. PMID:19910890
Quinn, G P; Vadaparampil, S T; Bower, B; Friedman, S; Keefe, D L
Preimplantation genetic diagnosis: an ambiguous legal status for an ambiguous medical and social practice.
Preimplantation Genetic Diagnosis (PGD) is a technique that is strictly regulated in most European countries where it is regularly practised, the legal status of PGD may appear to some as unethical because it may be viewed as a facilitator for those who would like to select children for reason other than medical. The need to test human embryos before birth and the consequences that may occur to those detected with some abnormalities also revives the issue of the respect due to the human embryo. In this paper the author analyse these matters. PMID:18942507
Christian, B Y K
Reliable preimplantation genetic diagnosis in thawed human embryos vitrified at cleavage stages without biopsy
Purpose��To evaluate preimplantation genetic diagnosis (PGD) efficiency in thawed human embryos vitrified without biopsy.\\u000a \\u000a \\u000a \\u000a Methods��In this retrospective clinical study, 21 PGD cycles were carried out using fresh and vitrified-thawed embryos collected from\\u000a 21 patients.\\u000a \\u000a \\u000a \\u000a \\u000a Results��One hundred and ninety-nine embryos from patients with aneuploidy, single gene defects, or chromosomal translocations were\\u000a vitrified at the cleavage stages; 93.5% of the embryos survived
Li Zhang; Ahmet Yilmaz; Ri-Cheng Chian; Weon-Young Son; Xiao Yun Zhang; Dewen Kong; Michael Dahan; Hannanel Holzer; Seang Lin Tan; Asangla Ao
Multiplex sequence variation detection throughout the CFTR gene appropriate for preimplantation genetic diagnosis in populations with heterogeneity of cystic fibrosis mutations
Cystic fibrosis (CF) is one of the most important genetic diseases requiring prevention programmes. Preimplantation genetic diagnosis (PGD) represents an alternative to prenatal diagnosis, and is especially appropriate for couples with an unsuccessful reproductive history. For clinical application, protocols must be optimized to minimize PCR failure, allelic drop-out (ADO) and contamination, while simultaneously detecting a wide spectrum of CF genotypes.
Christina Vrettou; Maria Tzetis; Joanne Traeger-Synodinos; Giles Palmer; Emmanuel Kanavakis
An update of preimplantation genetic diagnosis in gene diseases, chromosomal translocation, and aneuploidy screening
Preimplantation genetic diagnosis (PGD) is gradually widely used in prevention of gene diseases and chromosomal abnormalities. Much improvement has been achieved in biopsy technique and molecular diagnosis. Blastocyst biopsy can increase diagnostic accuracy and reduce allele dropout. It is cost-effective and currently plays an important role. Whole genome amplification permits subsequent individual detection of multiple gene loci and screening all 23 pairs of chromosomes. For PGD of chromosomal translocation, fluorescence in-situ hybridization (FISH) is traditionally used, but with technical difficulty. Array comparative genomic hybridization (CGH) can detect translocation and 23 pairs of chromosomes that may replace FISH. Single nucleotide polymorphisms array with haplotyping can further distinguish between normal chromosomes and balanced translocation. PGD may shorten time to conceive and reduce miscarriage for patients with chromosomal translocation. PGD has a potential value for mitochondrial diseases. Preimplantation genetic haplotyping has been applied for unknown mutation sites of single gene disease. Preimplantation genetic screening (PGS) using limited FISH probes in the cleavage-stage embryo did not increase live birth rates for patients with advanced maternal age, unexplained recurrent abortions, and repeated implantation failure. Polar body and blastocyst biopsy may circumvent the problem of mosaicism. PGS using blastocyst biopsy and array CGH is encouraging and merit further studies. Cryopreservation of biopsied blastocysts instead of fresh transfer permits sufficient time for transportation and genetic analysis. Cryopreservation of embryos may avoid ovarian hyperstimulation syndrome and possible suboptimal endometrium.
Chang, Li-Jung; Chen, Shee-Uan; Tsai, Yi-Yi; Hung, Chia-Cheng; Fang, Mei-Ya
Parental mosaicism is a pitfall in preimplantation genetic diagnosis of dominant disorders.
PCR amplification on single cells is prone to allele drop-out (PCR failure of one allele), a cause of misdiagnosis in preimplantation genetic diagnosis (PGD). Owing to this error risk, PGD usually relies on both direct and indirect genetic analyses. When the affected partner is the sporadic case of a dominant disorder, building haplotypes require spermatozoon or polar body testing prior to PGD, but these procedures are cost and time-consuming. A couple requested PGD because the male partner suffered from a dominant Cowden syndrome (CS). He was a sporadic case, but the couple had a first unaffected child and the non-mutated paternal haplotype was tentatively deduced. The couple had a second spontaneous pregnancy and the fetus was found to carry the at-risk haplotype but not the PTEN mutation. The mutation was present in blood from the affected father, but at low level, confirming the somatic mosaicism. Ignoring the possibility of mosaicism in the CS patient would have potentially led to selection of affected embryos. This observation emphasizes the risk of PGD in families at risk to transmit autosomal-dominant disorder when the affected partner is a sporadic case. PMID:24022303
Steffann, Julie; Michot, Caroline; Borghese, Roxana; Baptista-Fernandes, Marcia; Monnot, Sophie; Bonnefont, Jean-Paul; Munnich, Arnold
On new reproductive technologies and family ethics: pre-implantation genetic diagnosis for sibling donor in Israel and Germany.
This paper discusses the policy debate and ethical discussion surrounding pre-implantation genetic diagnosis (PGD) for sibling donor (SD) in Germany and Israel. Based on an analysis of the regulations and ethical discourse concerning a unique form of new reproductive technology (NRT)--PGD for SD--we complement the scholarly discussion of NRTs in these countries, by pointing to an explanatory factor that has been so far neglected, namely the hegemonic notions regarding the ideal relationship between the generations, and the mutual obligations between different family members in Germany and Israel. We argue the fact that PGD (in general) and PGD for SD (in particular) have been banned in Germany, but were endorsed without hesitation in Israel, has to do with different perceptions of family ethics within the two societies. Furthermore, we argue that this factor contributes significantly to the more general understanding of German and Israeli policies regarding NRTs. PMID:17669568
Hashiloni-Dolev, Yael; Shkedi, Shiri
The minisequencing method: an alternative strategy for preimplantation genetic diagnosis of single gene disorders
We have applied a new method of genetic analysis, called 'minisequencing', to preimplantation genetic diagnosis (PGD) of monogenic disorders from single cells. This method involves computer-assisted mutation analysis, which allows exact base identity determination and computer-assisted visualization of the specific mutation(s), and thus facilitates data interpretation and management. Sequencing of the entire PCR product is unnecessary, yet the same qualitative
F. Fiorentino; M. C. Magli; D. Podini; A. P. Ferraretti; A. Nuccitelli; N. Vitale; M. Baldi; L. Gianaroli
Pre-implantation genetic diagnosis is an alternative to prenatal diagnosis for a select group of patients. Patients have to go through in vitro fertilization in order to produce embryos in vitro, from which one or two cells are removed at the 8-cell stage. A fluorescence in situ hybridization or polymerase chain reaction is carried out for the genetic diagnosis. Fluorescence in
Joyce C Harper
Simplified PGD of common determinants of haemoglobin Bart�s hydrops fetalis syndrome using multiplex-microsatellite PCR
The high incidence of double-gene deletions in ?-thalassaemia increases the risk of having pregnancies with homozygous ?0-thalassaemia, the cause of the lethal haemoglobin (Hb) Bart�s hydrops fetalis syndrome. Preimplantation genetic diagnosis (PGD) has played an important role in preventing such cases. However, the current gap-PCR based PGD protocol for deletional ?-thalassaemia requires specific primer design for each specific deletion. A
Wen Wang; Christine H. A. Yap; Seong Feei Loh; Arnold S. C. Tan; Mui Nee Lim; Ethiraj B. Prasath; Melinda L. H. Chan; Wei Chin Tan; Boran Jiang; Gare Hoon Yeo; Joyce Mathew; Angela Ho; Sherry S. Y. Ho; Peng Cheang Wong; Mahesh A. Choolani; Samuel S. Chong
Providing preimplantation genetic diagnosis in the United Kingdom, The Netherlands and Germany: a comparative in-depth analysis of health-care access.
In recent years, preimplantation genetic diagnosis (PGD) has developed into a routine diagnostic procedure in health care. Although during this process, several initiatives have been employed to regulate the procedure, access to PGD may be hampered by the diversity in health-care arrangements or therapeutic cultures in different countries. This article demonstrates how PGD provision practices depend on much more than regulation alone, by providing an in-depth comparative analysis of the provision of PGD in Britain, the Netherlands and Germany. In analysing regulation, organization, selection of indications, and mechanisms and criteria for reimbursement, differences between these countries can be identified. This is important, since differences in PGD provision can have enormous consequences for the access of individual patients in different countries. Somewhat paradoxically, this article concludes that even though differences in access do have serious consequences, they also serve the establishment of PGD. Developing access to PGD in national 'therapeutic cultures' can contribute to making PGD routine health care in a way that may not be achievable by harmonizing regulation. PMID:19279036
Aarden, Erik; Van Hoyweghen, Ine; Vos, Rein; Horstman, Klasien
Preimplantation genetic diagnosis for ?-thalassaemia using sequencing of single cell PCR products to detect mutations and polymorphic loci
In order to carry out preimplantation genetic diagnosis (PGD) for ?-thalassaemia, we have applied direct sequencing of single cell PCR products to detect mutations and polymorphic loci within the ?-globin gene. Conventional duplex PCR was used to amplify two regions of the ?-globin gene with an amplification efficiency of 79% for blastomeres. Sequencing data were obtained for 100% of amplified
Nicole D. Hussey; Tenielle Davis; Jenny R. Hall; Michael F. Barry; Rogan Draper; Robert J. Norman; Zbigniew Rudzki
The development of preimplantation genetic diagnosis for myotonic dystrophy using multiplex fluorescent polymerase chain reaction and its clinical application
Preimplantation genetic diagnoses (PGD) for single gene defects require considerable time and resources for the standardization of polymerase chain reactions that are rapid, sensitive and reliable. Developing tests for the trinucleotide repeat diseases, where the expansion of unstable repeats produces the phenotypes, are particularly complex. One of these disorders is myotonic dystrophy where, at present, diagnosis at the single cell
N. L. Dean; S. L. Tan; A. Ao
Controlling misdiagnosis errors in preimplantation genetic diagnosis: a comprehensive model encompassing extrinsic and intrinsic sources of error
We have developed a mathematical model to explore accuracy of preimplantation genetic diagnosis (PGD) using single cell polymerase chain reaction (PCR). The model encompasses both extrinsic technical errors and intrinsic errors related to nuclear and chromosomal abnormalities. Using estimates for these errors, we have calculated the probability of a serious error (affected embryo diagnosed as unaffected) using a variety of
C. M. Lewis; T. Pinel; J. C. Whittaker; A. H. Handyside
Successful Hematopoietic Stem Cell Transplantation for Fanconi Anemia from an Unaffected HLA Genotypically Identical Sibling Selected Using Preimplantation Genetic Diagnosis
The only proven cure for Fanconi anemia (FA)-associated bone marrow failure is successful allogeneic hematopoietic stem cell transplantation (HSCT). However, HSCT with donors other than HLA-identi- cal siblings is associated with high mor- bidity and poor survival. Therefore, we used preimplantation genetic diagnosis (PGD) to select an embryo produced by in vitro fertilization (IVF) that was unaffected by FA and
Jeffrey P Kahn; Margaret L MacMillan; Norma KC Ramsay; John E Wagner
The case for a parental duty to use preimplantation genetic diagnosis for medical benefit.
This article explores the possibility that there is a parental duty to use preimplantation genetic diagnosis (PGD) for the medical benefit of future children. Using one genetic disorder as a paradigmatic example, we find that such a duty can be supported in some situations on both ethical and legal grounds. Our analysis shows that an ethical case in favor of this position can be made when potential parents are aware that a possible future child is at substantial risk of inheriting a serious genetic condition. We further argue that a legal case for a duty to use PGD for medical benefit can be made in situations in which potential parents have chosen to conceive through in vitro fertilization and know that any children conceived are at substantial risk of having a serious genetic condition. PMID:22452463
Malek, Janet; Daar, Judith
Perinatal genetics: Diagnosis and treatment
SciTech Connect
This book consists of six sections, each containing several chapters. Some of the chapter titles are: Prenatal Diagnosis of the Fragile X Syndrome; Prenatal Genetic Diagnosis by Chorionic Villus Sampling; Prenatal Treatment of Biochemical Disorders; H-Y Antigen, Sex Determination and Gender Control; and Environmental Factors and Human Birth Defects: Interpretation of Relative Risks in Clinical Genetics.
Porter, I.H.; Hatcher, N.H.; Willey, A.M.
Pandora's box: ethics of PGD for inherited risk of late-onset disorders.
Until recently, the primary use of preimplantation genetic diagnosis (PGD) has been the selection of embryos to avoid lethal or debilitating gene mutations or abnormal chromosome complement. PGD can be used to reduce the risk of transferring to the uterus an embryo with Down syndrome, and parents who are carriers of severe genetic diseases may choose to avoid having children with these debilitating genetic conditions. The use of PGD is now being extended to include gene mutations that increase the risk of late-onset disorders such as breast and ovarian cancer. This paper argues for caution in advocating reproductive methods that are costly, have a limited chance of success, and for which the long-term outcome is unknown. Counselling should allow women a true choice of declining the option of PGD without recrimination, feelings of guilt or social pressure. There is concern that the Human Fertilisation and Embryology Authority has approved extension of PGD to late-onset multifactorial diseases without clear guidelines for its use. Guidelines for embryo selection should be revised to deal with potential conflict between reproductive success and genetic screening for disorders that do not profoundly affect the embryo or the children. PMID:18983739
Noble, Ray; Bahadur, Gulam; Iqbal, Mohammad; Sanyal, Arnab
Is there an ethical difference between preimplantation genetic diagnosis and abortion?
When a person at risk of having a child with a genetic illness or disease wishes to have an unaffected child, this can involve difficult choices. If the pregnancy is established by sexual intercourse, the fetus can be tested early in pregnancy, and if affected a decision can be made to abort in the hope that a future pregnancy with an unaffected fetus ensures. Alternatively, preimplantation genetic diagnosis (PGD) can be used after in vitro fertilisation (IVF) to select and implant an unaffected embryo that hopefully will proceed to term and produce a healthy baby. We are aware that many individuals at risk regard the latter as ethically more acceptable than the former, and examine whether there is an ethical difference between these options. We conclude that PGD and implantation of an unaffected embryo is a more acceptable choice ethically than prenatal diagnosis (PND) followed by abortion for the following reasons:
Cameron, C; Williamson, R
Conceptualizing Couples' Decision Making in PGD: Emerging Cognitive, Emotional, and Moral Dimensions
Objective To illuminate and synthesize what is known about the underlying decision making processes surrounding couples� preimplantation genetic diagnosis (PGD) use or disuse and to formulate an initial conceptual framework that can guide future research and practice. Methods This systematic review targeted empirical studies published in English from 1990 to 2008 that examined the decision making process of couples or individual partners that had used, were eligible for, or had contemplated PGD. Sixteen studies met the eligibility requirements. To provide a more comprehensive review, empirical studies that examined healthcare professionals� perceptions of couples� decision making surrounding PGD use and key publications from a variety of disciplines supplemented the analysis. Results The conceptual framework formulated from the review demonstrates that couples� PGD decision making is composed of three iterative and dynamic dimensions: cognitive appraisals, emotional responses, and moral judgments. Conclusion Couples think critically about uncertain and probabilistic information, grapple with conflicting emotions and incorporate moral perspectives into their decision making about whether or not to use PGD. Practice Implications The quality of care and decisional support for couples who are contemplating PGD use can be improved by incorporating focused questions and discussion from each of the dimensions into counseling sessions.
Hershberger, Patricia E.; Pierce, Penny F.
Moral attitudes and beliefs among couples pursuing PGD for sex selection.
This article reports the results from a study of couples participating in a research protocol in which IVF/preimplantation genetic diagnosis (PGD) was available for non-medical sex selection. The study sought to characterize the moral attitudes and beliefs of couples actively pursuing IVF/PGD solely for purposes related to sex selection. Eighteen couples participated in ethnographic interviews from November 2005 to April 2006. These interviews explored couples' motivations for pursuing sex selection, moral beliefs and attitudes regarding sex selection and sources of moral ambivalence about the use of IVF/PGD for sex selection. Couples reported a combination of motivations for pursuing sex selection, including a desire to limit family size, concerns about parental age and financial concerns about multiple pregnancies. Many couples compared their decision to choices about abortion, maintaining that individuals have a right to make such decisions privately. Couples frequently expressed anxiety about telling their other children and family members about their plans to use IVF/PGD for sex selection. Few couples cited concerns about the physical or emotional burdens of IVF/PGD. The study's findings suggest that couples pursuing IVF/PGD for sex selection view this as an ethically complex decision and express considerable uncertainty about the ethical acceptability of this practice. PMID:21051290
Sharp, Richard R; McGowan, Michelle L; Verma, Jonathan A; Landy, David C; McAdoo, Sallie; Carson, Sandra A; Simpson, Joe Leigh; McCullough, Laurence B
Identification of embryonic chromosomal abnormality using FISH-based preimplantaion genetic diagnosis
Objective: Embryonic chromosomal abnormality is one of the main reasons for in vitro fertilization (IVF) failure. This study\\u000a aimed at evaluating the value of Fluorescence in-situ Hybridization (FISH)-based Preimplantation Genetic Diagnosis (PGD) in\\u000a screening for embryonic chromosomal abnormality to increase the successful rate of IVF. Method: Ten couples, four with high\\u000a risk of chromosomal abnormality and six infertile couples, underwent
Ying-hui Ye; Chen-ming Xu; Fan Jin; Yu-li Qian
Pregnancy following intracytoplasmic sperm injection and preimplantation genetic diagnosis after the conservative management of endometrial cancer
A rare case of a patient with conservatively treated endometrial carcinoma who conceived and delivered a healthy baby after the transfer of embryos with intracytoplasmic sperm injection (ICSI) and preimplantation genetic diagnosis (PGD) is presented. A 41-year-old woman had an office hysteroscopy in the infertility work-up and stage I endometrial adenocarcinoma was diagnosed. After conservative treatment, the patient underwent ICSI
A Demirol; M Bahce; A Ayhan; T Gurgan
Knowledge, attitudes, and clinical experience of physicians regarding preimplantation genetic diagnosis for hereditary cancer predisposition syndromes
Approximately 5�10% of cancers are caused by an inherited predisposition. Individuals affected by hereditary cancer are often\\u000a concerned about transmitting a predisposition to cancer to their children. Preimplantation genetic diagnosis (PGD) is a technology\\u000a that allows embryos without a deleterious mutation associated with a hereditary cancer syndrome to be identified and implanted.\\u000a The aim of this study is to assess
Amanda C. BrandtMatthew; Matthew L. Tschirgi; Kaylene J. Ready; Charlotte Sun; Sandra Darilek; Jacqueline Hecht; Banu K. Arun; Karen H. Lu
Prevention of lysosomal storage diseases and derivation of mutant stem cell lines by preimplantation genetic diagnosis.
Preimplantation genetic diagnosis (PGD) allows birth of unaffected children for couples at risk for a genetic disorder. We present the strategy and outcome of PGD for four lysosomal storage disorders (LSD): Tay-Sachs disease (TSD), Gaucher disease (GD), Fabry disease (FD), and Hunter syndrome (HS), and subsequent development of stem cell lines. For each disease, we developed a family-specific fluorescent multiplex single-cell PCR protocol that included the familial mutation and informative markers surrounding the mutation. Embryo biopsy and PGD analysis were performed on either oocytes (polar bodies one and two) or on single blastomeres from a six-cell embryo. We treated twenty families carrying mutations in these lysosomal storage disorders, including 3 couples requiring simultaneous analysis for two disorders (TSD/GD, TSD/balanced Robertsonian translocation 45XYder(21;14), and HS/oculocutaneus albinism). These analyses led to an overall pregnancy rate/embryo transfer of 38% and the birth of 20 unaffected children from 17 families. We have found that PGD for lysosomal disorders is a safe and effective method to prevent birth of affected children. In addition, by using mutant embryos for the derivation of stem cell lines, we have successfully established GD and HS hESC lines for use as valuable models in LSD research. PMID:23320174
Altarescu, Gheona; Beeri, Rachel; Eiges, Rachel; Epsztejn-Litman, Silvina; Eldar-Geva, Talia; Elstein, Deborah; Zimran, Ari; Margalioth, Ehud J; Levy-Lahad, Ephrat; Renbaum, Paul
Preimplantation genetic diagnosis, reproductive freedom, and deliberative democracy.
In this paper I argue that the account of deliberative democracy advanced by Amy Gutmann and Dennis Thompson (1996, 2004) is a useful normative theory that can help enhance our deliberations about public policy in morally pluralistic societies. More specifically, I illustrate how the prescriptions of deliberative democracy can be applied to the issue of regulating non-medical uses of pre-implantation genetic diagnosis (PGD), such as gender selection. Deliberative democracy does not aim to win a philosophical debate among rival first-order theories, such as libertarianism, egalitarianism or feminism. Rather, it advances a second-order analysis that strives to help us determine what would constitute a reasonable balance between the conflicting fundamental values that arise in the context of regulating PGD. I outline a theoretical model (called the Reasonable Genetic Intervention Model) that brings these issues to the fore. Such a model incorporates the concern for both procedural and substantive principles; and it does so in way that takes provisionality seriously. PMID:19251775
Farrelly, Colin
[Preimplantation diagnosis with HLA typing: birth of the first double hope child in France].
Preimplantation genetic diagnosis (PGD) is authorized in France since 1999. After 10 years, technical results are encouraging. With the development of new technologies, our team is able to diagnosis the large majority of chromosome translocations and 75 monogenic diseases. However, PGD remains limited because of the growing augmentation of demands causing an increasing delay for the first procedure of more than 18 months. Since 2006, 19 couples asked for a PGD with HLA typing. In January 2011, 11 couples have already been included in our PGD program. The birth of the first child after PGD with HLA typing offers new perspectives of treatment for these couples. PMID:21944578
Lamazou, F; Steffann, J; Frydman, N; Burlet, P; Gigarel, N; Romana, S; Bonnefont, J-P; Lelorch, M; Hesters, L; Fanchin, R; Kerbrat, V; Vekemans, M; Munnich, A; Frydman, R
Preimplantation genetic diagnosis: understanding what parents plan to tell their children about their conception.
Over 10,000 babies have been born by PGD and PGS worldwide (Simpson, Prenatal Diagnosis 30(7): 682-695 2010). The experience of parents who have undergone this procedure and their children's well-being are documented, but no research to date has explored whether parents intend to tell their children how they were conceived and whether this raises special issues for them. PGD practitioners recommend research in this area as parents of children born by PGD increasingly ask questions pertaining to disclosure. We conducted 30 in-depth interviews with couples who have had a baby conceived by PGD. We explored what couples plan to tell their children about how they were conceived, when they plan to do this, and issues they anticipate may arise. The couples had a family history of a monogenic disorder or chromosome rearrangement. Six themes emerged which highlight key issues: (1) To tell or not to tell? (2) Primary reason for undergoing PGD, (3) The ideal time to tell, (4) Situations which may warrant earlier disclosure, (5) Words which parents might choose, and (6) Issues which parents anticipate may arise. We conclude that parents are likely to inform their children about PGD because there is an affected sibling or relative about whom they ask questions, and/or their children are carriers of a condition their parents feel obliged to tell them about. Parents felt they would benefit from access to a genetic counsellor at the time of disclosure and are optimistic about the future of reproductive technology for their children. PMID:23613153
Kosicka-Slawinska, Monika; Clarke, Angus; Lashwood, Alison
Preimplantation genetic diagnosis for mitochondrial DNA disorders: ethical guidance for clinical practice.
Although morally acceptable in theory, preimplantation genetic diagnosis (PGD) for mitochondrial DNA (mtDNA) disorders raises several ethical questions in clinical practice. This paper discusses the major conditions for good clinical practice. Our starting point is that PGD for mtDNA mutations should as far as possible be embedded in a scientific research protocol. For every clinical application of PGD for mtDNA disorders, it is not only important to avoid a 'high risk of serious harm' to the future child, but also to consider to what extent it would be possible, desirable and proportional to try to reduce the health risks and minimize harm. The first issue we discuss is oocyte sampling, which may point out whether PGD is feasible for a specific couple. The second issue is whether one blastomere represents the genetic composition of the embryo as a whole -- and how this could (or should) be investigated. The third issue regards the cutoff points below which embryos are considered to be eligible for transfer. We scrutinize how to determine these cutoff points and how to use these cutoff points in clinical practice -- for example, when parents ask to take more or less risks. The fourth issue regards the number of cycles that can (or should) justifiably be carried out to find the best possible embryo. Fifth, we discuss whether follow-up studies should be conducted, particularly the genetic testing of children born after IVF/PGD. Finally, we offer the main information that is required to obtain a truly informed consent. PMID:19471315
Bredenoord, Annelien; Dondorp, Wybo; Pennings, Guido; de Die-Smulders, Christine; Smeets, Bert; de Wert, Guido
Preimplantation genetic diagnosis for mitochondrial DNA disorders: ethical guidance for clinical practice
Although morally acceptable in theory, preimplantation genetic diagnosis (PGD) for mitochondrial DNA (mtDNA) disorders raises several ethical questions in clinical practice. This paper discusses the major conditions for good clinical practice. Our starting point is that PGD for mtDNA mutations should as far as possible be embedded in a scientific research protocol. For every clinical application of PGD for mtDNA disorders, it is not only important to avoid a �high risk of serious harm' to the future child, but also to consider to what extent it would be possible, desirable and proportional to try to reduce the health risks and minimize harm. The first issue we discuss is oocyte sampling, which may point out whether PGD is feasible for a specific couple. The second issue is whether one blastomere represents the genetic composition of the embryo as a whole � and how this could (or should) be investigated. The third issue regards the cutoff points below which embryos are considered to be eligible for transfer. We scrutinize how to determine these cutoff points and how to use these cutoff points in clinical practice � for example, when parents ask to take more or less risks. The fourth issue regards the number of cycles that can (or should) justifiably be carried out to find the best possible embryo. Fifth, we discuss whether follow-up studies should be conducted, particularly the genetic testing of children born after IVF/PGD. Finally, we offer the main information that is required to obtain a truly informed consent.
The first successful live birth following preimplantation genetic diagnosis using PCR for type 1 citrullinemia.
Type 1 citrullinemia (CTLN1) is an autosomal recessive inherited metabolic disorder caused by anargininosuccinicnate synthetase deficiency. The patient was a 38-year-old Korean woman who is a carrier for CTLN1 and her first baby was diagnosed with CTLN1. Preimplantation genetic diagnosis (PGD) for CTLN1 in day 3 embryos using polymerase chain reaction was performed for live birth of healthy baby who is no affected with CTLN1. One unaffected blastocyst was transferred. This resulted in a clinical pregnancy and the live birth of healthy male twin. They were confirmed to be unaffected with CTNL1 by post natal diagnosis. This is the first case report of the use of PGD for CTNL1. PMID:24883299
Cho, Jae-Hyun; Kim, Chung-Hoon; Lee, Kyung-Hee; Jeon, Il-Kyung; Kim, Jae-Min; Kang, Byung-Moon
The first successful live birth following preimplantation genetic diagnosis using PCR for type 1 citrullinemia
Type 1 citrullinemia (CTLN1) is an autosomal recessive inherited metabolic disorder caused by anargininosuccinicnate synthetase deficiency. The patient was a 38-year-old Korean woman who is a carrier for CTLN1 and her first baby was diagnosed with CTLN1. Preimplantation genetic diagnosis (PGD) for CTLN1 in day 3 embryos using polymerase chain reaction was performed for live birth of healthy baby who is no affected with CTLN1. One unaffected blastocyst was transferred. This resulted in a clinical pregnancy and the live birth of healthy male twin. They were confirmed to be unaffected with CTNL1 by post natal diagnosis. This is the first case report of the use of PGD for CTNL1.
Cho, Jae-Hyun; Lee, Kyung-Hee; Jeon, Il-Kyung; Kim, Jae-Min; Kang, Byung-Moon
Queerin' the PGD clinic : human enhancement and the future of bodily diversity.
Disability activists influenced by queer theory and advocates of "human enhancement" have each disputed the idea that what is "normal" is normatively significant, which currently plays a key role in the regulation of pre-implantation genetic diagnosis (PGD). Previously, I have argued that the only way to avoid the implication that parents have strong reasons to select children of one sex (most plausibly, female) over the other is to affirm the moral significance of sexually dimorphic human biological norms. After outlining the logic that generates this conclusion, I investigate the extent to which it might also facilitate an alternative, progressive, opening up of the notion of the normal and of the criteria against which we should evaluate the relative merits of different forms of embodiment. This paper therefore investigates the implications of ideas derived from queer theory for the future of PGD and of PGD for the future of queerness. PMID:23468396
Sparrow, Robert
Preimplantation genetic diagnosis for gender selection in the USA.
Preimplantation genetic diagnosis (PGD) for gender selection for non-medical reasons has been considered an unethical procedure by several authors and agencies in the Western society on the basis that it could disrupt the sex ratio, that it discriminates against women and that it leads to disposal of normal embryos of the non-desired gender. In this study, the analysis of a large series of PGD procedures for gender selection from a wide geographical area in the USA shows that, in general, there is no deviation in preference towards any specific gender except for a preference of males in some ethnic populations of Chinese, Indian and Middle Eastern origin that represent a small percentage of the US population. In cases where only normal embryos of the non-desired gender are available, 45.5% of the couples elect to cancel the transfer, while 54.5% of them are open to have embryos transferred of the non-desired gender, this fact being strongly linked to cultural and ethnic background of the parents. In addition this study adds some evidence to the proposition that, in couples with previous children of a given gender, there is no biological predisposition towards producing embryos of that same gender. Based on these facts, it seems that objections to gender selection formulated by ethics committees and scientific societies are not well founded. PMID:19891844
Colls, P; Silver, L; Olivera, G; Weier, J; Escudero, T; Goodall, N; Tomkin, G; Munn�, S
Preimplantation genetic diagnosis for gender selection in the United States
Preimplantation genetic diagnosis (PGD) of gender selection for non medical reasons has been considered an unethical procedure by several authors and agencies in the Western society on the basis of disrupting the sex ratio, being discriminatory againsts women and disposal of normal embryos of the non desired gender. In this study, the analysis of a large series of PGD procedures for gender selection from a wide geographical area in the United States, shows that in general there is no deviation in preference towards any specific gender except for a preference of males in some ethnic populations of Chinese, Indian and Middle Eastern origin that represent a small percentage of the US population. In cases where only normal embryos of the non-desired gender are available, 45.5% of the couples elect to cancel the transfer, while 54.5% of them are open to have transferred embryos of the non-desired gender, this fact being strongly linked to cultural and ethnical background of the parents. In addition this study adds some evidence to the proposition that in couples with previous children of a given gender there is no biological predisposition towards producing embryos of that same gender. Based on these facts, it seems that objections to gender selection formulated by ethics committees and scientific societies are not well-founded.
Colls, P.; Silver, L.; Olivera, G.; Weier, J.; Escudero, T.; Goodall, N.; Tomkin, G.; Munne, S.
The experience of 3 years of external quality assessment of preimplantation genetic diagnosis for cystic fibrosis.
Preimplantation genetic diagnosis (PGD) was first performed over 20 years ago and has become an accepted part of genetic testing and assisted reproduction worldwide. The techniques and protocols necessary to carry out genetic testing at the single-cell level can be difficult to master and have been developed independently by the laboratories worldwide offering preimplantation testing. These factors indicated the need for an external quality assessment (EQA) scheme for monogenic disease PGD. Toward this end, the European Society for Human Reproduction and Embryology came together with United Kingdom National External Quality Assessment Services for Molecular Genetics, to create a pilot EQA scheme followed by practical EQA schemes for all interested parties. Here, we detail the development of the pilot scheme as well as development and findings from the practical (clinical) schemes that have followed. Results were generally acceptable and there was marked improvement in results and laboratory scores for those labs that participated in multiple schemes. Data from the first three schemes indicate that the EQA scheme is working as planned and has helped laboratories improve their techniques and result reporting. The EQA scheme for monogenic PGD will continue to be developed to offer assessment for other monogenic disorders. PMID:23150080
Deans, Zandra; Fiorentino, Francesco; Biricik, Anil; Traeger-Synodinos, Joanne; Moutou, C�line; De Rycke, Martine; Renwick, Pamela; Sengupta, Sioban; Goossens, Veerle; Harton, Gary
The Decision-Making Process of Genetically At-Risk Couples Considering Preimplantation Genetic Diagnosis: Initial Findings from a Grounded Theory Study
Exponential growth in genomics has led to public and private initiatives worldwide that have dramatically increased the number of procreative couples who are aware of their ability to transmit genetic disorders to their future children. Understanding how couples process the meaning of being genetically at risk for their procreative life lags far behind the advances in genomic and reproductive sciences. Moreover, society, policy makers, and clinicians are not aware of the experiences and nuances involved when modern couples are faced with using Preimplantation Genetic Diagnosis (PGD). The purpose of this study was to discover the decision-making process of genetically at-risk couples as they decide whether to use PGD to prevent the transmission of known single-gene or sex-linked genetic disorders to their children. A qualitative, grounded theory design guided the study in which 22 couples (44 individual partners) from the USA, who were actively considering PGD, participated. Couples were recruited from June 2009 to May 2010 from the Internet and from a large PGD center and a patient newsletter. In-depth semi-structured interviews were completed with each individual partner within the couple dyad, separate from their respective partner. We discovered that couples move through four phases (Identify, Contemplate, Resolve, Engage) of a complex, dynamic, and iterative decision-making process where multiple, sequential decisions are made. In the Identify phase, couples acknowledge the meaning of their at-risk status. Parenthood and reproductive options are explored in the Contemplate phase, where 41% of couples remained for up to 36 months before moving into the Resolve phase. In Resolve, one of three decisions about PGD use is reached, including: Accepting, Declining, or Oscillating. Actualizing decisions occur in the Engage phase. Awareness of the decision-making process among genetically at-risk couples provides foundational work for understanding critical processes and aids in identifying important gaps for intervention and future research.
Hershberger, Patricia E.; Gallo, Agatha M.; Kavanaugh, Karen; Olshansky, Ellen; Schwartz, Alan; Tur-Kaspa, Ilan
Creating a Stem Cell Donor: A Case Study in Reproductive Genetics
During the nearly 10 years since its introduction, preimplantation genetic diagnosis (PGD) has been used predominantly to avoid giving birth to a child with identified genetic disease. Recently, PGD was used by a couple not only to test IVF-created embryos for genetic disease, but also to test for a nondisease trait related to immune compatibility with a child in the
Jeffrey P. Kahn; Anna C. Mastroianni
First successful double-factor PGD for Lynch syndrome: monogenic analysis and comprehensive aneuploidy screening.
Preimplantation genetic diagnosis (PGD) has been applied worldwide for a great variety of single-gene disorders over the last 20?years. The aim of this work was to perform a double-factor preimplantation genetic diagnosis (DF-PGD) protocol in a family at risk for Lynch syndrome. The family underwent a DF-PGD approach in which two blastomeres from each cleavage-stage embryo were biopsied and used for monogenic and comprehensive cytogenetic analysis, respectively. Fourteen embryos were biopsied for the monogenic disease and after multiple displacement amplification (MDA), 12 embryos were diagnosed; 5 being non-affected and 7 affected by the disease. Thirteen were biopsied to perform the aneuploidy screening by short-comparative genomic hybridization (CGH). The improved DF-PGD approach permitted the selection of not only healthy but also euploid embryos for transfer. This has been the first time a double analysis of embryos has been performed in a family affected by Lynch syndrome, resulting in the birth of two healthy children. The protocol described in this work offers a reliable alternative for single-gene disorder assessment together with a comprehensive aneuploidy screening of the embryos that may increase the chances of pregnancy and birth of transferred embryos. PMID:22998423
Daina, G; Ramos, L; Obradors, A; Rius, M; Martinez-Pasarell, O; Polo, A; Del Rey, J; Obradors, J; Benet, J; Navarro, J
The right not to know and preimplantation genetic diagnosis for Huntington's disease.
The right not to know is underappreciated in policy-making. Despite its articulation in medical law and ethics, policy-makers too easily let other concerns override the right not to know. This observation is triggered by a recent decision of the Dutch government on embryo selection for Huntington's disease. This is a monogenetic debilitating disease without cure, leading to death in early middle age, and thus is a likely candidate for preimplantation genetic diagnosis (PGD). People possibly affected with the Huntington gene do not always want to know their genetic status themselves, which is very burdensome knowledge. For prospective parents, this creates a difficulty in having unaffected children through embryo selection without knowing their own genetic status. A solution is provided by the exclusion test: it allows embryo selection while honouring the parents' right not to know. The Dutch government however disallowed the exclusion test and chose to allow PGD on Huntington only for parents who test themselves first. To avoid "unnecessary" in-vitro fertilisation procedures for unaffected parents, prospective parents are "forced to know" before they can conceive through embryo selection. This article analyses the scope of the right not to know in the context of embryo selection against Huntington's disease. It concludes that the right not to know implies that PGD against Huntington should be allowed by means of the exclusion test. PMID:20026690
Asscher, E; Koops, B-J
Healthy births and ongoing pregnancies obtained by preimplantation genetic diagnosis in patients with advanced maternal age and recurrent implantation failure
Preimplantation genetic diagnosis (PGD) and subsequent embryo development was evaluated in 72 couples presenting at our centre for intracytoplasmic sperm injection (ICSI) due to severe male factor. The embryo biopsies were performed in Ca2\\/Mg2-free medium. These patients were further divided into those with advanced maternal age (AMA, n 49) and those with recurrent implantation failure (RIF, n 23). Fluorescence in-situ
S. Kahraman; M. Bahce; H. Saml�; N. I �mirzal�og �lu; K. Yak�sn; G. Cengiz; E. Donmez
The development of novel quantification assay for mitochondrial DNA heteroplasmy aimed at preimplantation genetic diagnosis of Leigh encephalopathy
Purpose: To perform preimplantation genetic diagnosis (PGD) of Leigh encephalopathy, we developed a rapid and reliable quantification\\u000a assay for the percentage of T8993G mtDNA mutation and analyzed various specimens. Methods: We prepared the standard curve by measuring serial proportion of 8993T\\/G cloned plasmid DNA using real-time PCR, and measured\\u000a (1) mutant DNA (known proportions by PCR-RFLP), (2) single lymphocytes from
Hiroto Tajima; Kou Sueoka; Sung Yung Moon; Akira Nakabayashi; Tomoyoshi Sakurai; Yukitaka Murakoshi; Hiroyoshi Watanabe; Soukichi Iwata; Tsuyoshi Hashiba; Shingo Kato; Yu-Ichi Goto; Yasunori Yoshimura
Preimplantation genetic diagnosis in genomic regions with duplications and pseudogenes: long-range PCR in the single-cell assay.
Long-range PCR is generally employed for the analysis of disease-causing mutations in genes with homologous pseudogene copies. However, long-range PCR is challenging when performed on single cells, as in preimplantation genetic diagnosis (PGD) of monogenic disorders. PGD on single cells requires concurrent analysis of a mutation together with multiple linked polymorphic markers from closely related family members to prevent misdiagnosis. In PGD cases involving childless de novo mutation carriers, linkage cannot be performed based on family members but rather must first be identified in single gametes. This can be an especially difficult task if the mutation to be assayed lies in a duplicated genomic region because gene-specific long-range PCR must be coupled with short-range PCR analysis of genetic markers on single cells. Here, we describe a novel method by which accurate PGD of pseudogene-homologous mutations can be achieved. Essentially, we performed whole genome amplification on single sperm or blastomeres followed by haplotype construction and long-range PCR-based mutation analysis. This original and universal strategy was used to establish allelic association for two different mutations in genes with one or more pseudogene copies (IKBKG and PKD1). The method was also sensitive enough to detect unexpected germline mosaicism in one mutation carrier. PMID:23420578
Zeevi, David A; Renbaum, Paul; Ron-El, Raphael; Eldar-Geva, Talia; Raziel, Arieh; Brooks, Baruch; Strassburger, Dvorah; Margalioth, Ehud J; Levy-Lahad, Ephrat; Altarescu, Gheona
Facilitating choice, framing choice: staff views on widening the scope of preimplantation genetic diagnosis in the UK.
In the UK, the Human Fertilisation and Embryology Authority (HFEA) is responsible for licensing preimplantation genetic diagnosis (PGD). To date, licenses have been issued for the testing of about 70 genetic conditions, drawing on three key 'ethical principles'. Following a public consultation, the HFEA has recently widened the scope for PGD to include susceptibility to late onset, lower penetrance conditions such as inherited breast cancer. As the numbers and types of conditions which can potentially be tested for rises, the question of how, and indeed what limits should be set is timely. Drawing on qualitative interviews and ethics discussion groups which took place prior to or during the HFEA consultation, this paper explores the views of staff working in or linked to one PGD Unit in the UK, as to how they saw these potential changes. The paper thus provides an opportunity to develop greater understanding of how staff working in a morally contentious, innovative area viewed the potential expansion of their work, prior to that expansion taking place. Key themes include 'drawing lines' on behalf of others, particularly with the current emphasis on individual reproductive autonomy; and balancing the invasiveness and possible risks of PGD treatment against the 'seriousness' of the condition. More broadly, the paper highlights the complexities involved in trying to develop general 'ethical principles' to govern the use of ever evolving reproductive technologies. PMID:17573171
Williams, Clare; Ehrich, Kathryn; Farsides, Bobbie; Scott, Rosamund
Experience of preimplantation genetic diagnosis with HLA matching at the University Hospital Virgen del Roc�o in Spain: technical and clinical overview.
Preimplantation genetic diagnosis (PGD) of genetic diseases, combined with HLA matching (PGD-HLA), is an option for couples at risk of transmitting a genetic disease to select unaffected embryos of an HLA tissue type compatible with that of an existing affected child. Here we present the results of our PGD-HLA program at the Department of Genetics, Reproduction and Fetal Medicine of the University Hospital Virgen del Roc�o in Seville. Seven couples have participated in our program because of different indications. Overall, 26 cycles were performed, providing a total of 202 embryos. A conclusive molecular diagnosis and HLA-typing could be assured in 96% of the embryos. The percentage of transfers per cycle was 26.9% and the birth rate per cycle was 7.7% per transfer. Our PGD-HLA program resulted in the birth of 2 healthy babies, HLA-identical to their affected siblings, with successful subsequent haematopoietic stem cell (HSC) transplantations. Both HSC-transplanted children are currently doing well 48 and 21 months following transplantation, respectively. All the procedures, including HSCs umbilical cord transplantation, were performed in our hospital. PMID:24868528
Fern�ndez, Raquel Mar�a; Peci�a, Ana; Lozano-Arana, Maria Dolores; S�nchez, Beatriz; Guardiola, Jordi; Garc�a-Lozano, Juan Carlos; Borrego, Salud; Anti�olo, Guillermo
Experience of Preimplantation Genetic Diagnosis with HLA Matching at the University Hospital Virgen del Roc?o in Spain: Technical and Clinical Overview
Preimplantation genetic diagnosis (PGD) of genetic diseases, combined with HLA matching (PGD-HLA), is an option for couples at risk of transmitting a genetic disease to select unaffected embryos of an HLA tissue type compatible with that of an existing affected child. Here we present the results of our PGD-HLA program at the Department of Genetics, Reproduction and Fetal Medicine of the University Hospital Virgen del Roc�o in Seville. Seven couples have participated in our program because of different indications. Overall, 26 cycles were performed, providing a total of 202 embryos. A conclusive molecular diagnosis and HLA-typing could be assured in 96% of the embryos. The percentage of transfers per cycle was 26.9% and the birth rate per cycle was 7.7% per transfer. Our PGD-HLA program resulted in the birth of 2 healthy babies, HLA-identical to their affected siblings, with successful subsequent haematopoietic stem cell (HSC) transplantations. Both HSC-transplanted children are currently doing well 48 and 21 months following transplantation, respectively. All the procedures, including HSCs umbilical cord transplantation, were performed in our hospital.
Fernandez, Raquel Maria; Pecina, Ana; Lozano-Arana, Maria Dolores; Sanchez, Beatriz; Guardiola, Jordi; Garcia-Lozano, Juan Carlos; Borrego, Salud; Antinolo, Guillermo
Successful PGD for late infantile neuronal ceroid lipofuscinosis achieved by combined chromosome and TPP1 gene analysis.
Late infantile neuronal ceroid lipofuscinosis (NCL-2) is a severe debilitating autosomal recessive disease caused by mutations in TPP1. There are no effective treatments, resulting in early childhood death. A couple with two affected children presented for reproductive genetic counselling and chose to undertake IVF and preimplantation genetic diagnosis (PGD) to avoid the possibility of another affected child. However, DNA testing revealed only one mutation in the proband inherited from mother. Linkage analysis identified five informative linked short tandem repeat markers to aid the genetic diagnosis. Following IVF, five cleavage-stage embryos were biopsied and blastomeres were first subjected to whole-genome amplification, then a series of down-stream molecular genetic analyses to diagnose TPP1 genotype and finally array comparative genomic hybridization (CGH) to assess the chromosomal ploidy of each embryo. Two unaffected euploid embryos were identified for transfer. One was transferred on day 5 resulting in an ongoing pregnancy. Confirmatory prenatal diagnosis by amniocentesis showed concordance of the embryo and fetal diagnosis. As far as is known, this is the first successful report of PGD for NCL-2 using double-factor PGD with simultaneous single-gene testing and array CGH to identify an unaffected and chromosomally normal embryo for transfer. PMID:23768618
Shen, Jiandong; Cram, David Stephen; Wu, Wei; Cai, Lingbo; Yang, Xiaoyu; Sun, Xueping; Cui, Yugui; Liu, Jiayin
Single-cell polymerase chain reaction-based pre-implantation genetic diagnosis using fragment analysis for ?-thalassemia in an Indian couple with ?-globin gene mutations
Despite advances in diagnostic techniques, approximately 10,000 babies with ?-thalassemia major are born annually in India. Pre-implantation genetic diagnosis (PGD), an alternative to prenatal diagnosis, helps in negative selection of affected embryos prior to implantation. Hereby, we report the first successful ?-thalassemia PGD pregnancy in an Indian carrier couple. ?-Thalassemia mutation analysis by Amplification-Refractory Mutation Sequence (ARMS)-polymerase chain reaction (PCR) in the parents, followed by PGD for ?-thalassemia mutation in embryos in two consequent in vitro fertilization (IVF) cycles, with transfer for three ?-thalassemia minor embryos, resulted in singleton successful pregnancy, the results of which were confirmed on prenatal diagnosis. With advances in assisted reproductive techniques and molecular diagnosis, PGD for monogenic diseases is feasible in high-risk couples. The methodology in the current study included two rounds of PCR using fluorescently labeled primers, fragment analysis using the ABI 3100 nucleotide sequencer and the GeneMapper software, purification, and concentration of PCR product, which enabled distinct clear peaks making the analysis and interpretation non-ambiguous.
Saxena, Shailaja Gada; Saranath, Dhananjaya
Choosing embryos: ethical complexity and relational autonomy in staff accounts of PGD.
The technique of preimplantation genetic diagnosis (PGD) is commonly explained as a way of checking the genes of embryos produced by IVF for serious genetic diseases. However, complex accounts of this technique emerged during ethics discussion groups held for PGD staff. These form part of a study exploring the social processes, meanings and institutions that frame and produce 'ethical problems' for practitioners, scientists and others working in the specialty of PGD in the UK. Two 'grey areas' raised by staff are discussed in terms of how far staff are, or in the future may be, able to support autonomous choices of women/couples: accepting 'carrier' embryos within the goal of creating a 'healthy' child; and sex selection of embryos for social reasons. These grey areas challenged the staff's resolve to offer individual informed choice, in the face of their awareness of possible collective social effects that might ensue from individual choices. We therefore argue that these new forms of choice pose a challenge to conventional models of individual autonomy used in UK genetic and reproductive counselling, and that 'relational autonomy' may be a more suitable ethical model to describe the ethical principles being drawn on by staff working in this area. PMID:18092985
Ehrich, Kathryn; Williams, Clare; Farsides, Bobbie; Sandall, Jane; Scott, Rosamund
Single cell co-amplification of polymorphic markers for the indirect preimplantation genetic diagnosis of hemophilia�A, X-linked adrenoleukodystrophy, X-linked hydrocephalus and incontinentia pigmenti loci on Xq28
Preimplantation genetic diagnosis (PGD) first consisted of the selection of female embryos for patients at risk of transmitting X-linked recessive diseases. Advances in molecular biology now allow the specific diagnosis of almost any Mendelian disease. For families with an identified X-linked recessive disease-causing mutation, non-specific diagnosis by sex identification can be considered as a sub-standard method, since it involves the
Nadine Gigarel; Nelly Frydman; Philippe Burlet; Violaine Kerbrat; Julie Steffann; Ren� Frydman; Arnold Munnich; Pierre F. Ray
PGD for hereditary breast and ovarian cancer: the route to universal tests for BRCA1 and BRCA2 mutation carriers.
Preimplantation Genetic Diagnosis (PGD) is a method of testing in vitro embryos as an alternative to prenatal diagnosis with possible termination of pregnancy in case of an affected child. Recently, PGD for hereditary breast and ovarian cancer caused by BRCA1 and BRCA2 mutations has found its way in specialized labs. We describe the route to universal single-cell PGD tests for carriers of BRCA1/2 mutations. Originally, mutation-specific protocols with one or two markers were set up and changed when new couples were not informative. This route of changing protocols was finalized after 2 years with universal tests for both BRCA1 and BRCA2 mutation carriers based on haplotyping of, respectively, 6 (BRCA1) and 8 (BRCA2) microsatellite markers in a multiplex PCR. Using all protocols, 30 couples had a total of 47 PGD cycles performed. Eight cycles were cancelled upon IVF treatment due to hypostimulation. Of the remaining 39 cycles, a total of 261 embryos were biopsied and a genetic diagnosis was obtained in 244 (93%). In 34 of the 39 cycles (84.6%), an embryo transfer was possible and resulted in 8 pregnancies leading to a fetal heart beat per oocyte retrieval of 20.5% and a fetal heart beat per embryonic transfer of 23.5%. The preparation time and costs for set-up and validation of tests are minimized. The informativity of microsatellite markers used in the universal PGD-PCR tests is based on CEPH and deCODE pedigrees, making the tests applicable in 90% of couples coming from these populations. PMID:23531862
Dr�sedau, Marion; Dreesen, Jos C; Derks-Smeets, Inge; Coonen, Edith; van Golde, Ron; van Echten-Arends, Jannie; Kastrop, Peter M M; Blok, Marinus J; G�mez-Garc�a, Encarna; Geraedts, Joep P; Smeets, Hubert J; de Die-Smulders, Christine E; Paulussen, Aim�e D
Abnormal DLK1/MEG3 imprinting correlates with decreased HERV-K methylation after assisted reproduction and preimplantation genetic diagnosis.
Retrotransposons participate in cellular responses elicited by stress, and DNA methylation plays an important role in retrotransposon silencing and genomic imprinting during mammalian development. Assisted reproduction technologies (ARTs) may be associated with increased stress and risk of epigenetic changes in the conceptus. There are similarities in the nature and regulation of LTR retrotransposons and imprinted genes. Here, we investigated whether the methylation status of Human Endogenous Retroviruses (HERV)-K LTR retrotransposons and the imprinting signatures of the DLK1/MEG3. p57(KIP2) and IGF2/H19 gene loci are linked during early human embryogenesis by examining trophoblast samples from ART pregnancies and preimplantation genetic diagnosis (PGD) cases and matched naturally conceived controls. Methylation analysis revealed that HERV-Ks were totally methylated in the majority of controls while, in contrast, an altered pattern was detected in ART-PGD samples that were characterized by a hemi-methylated status. Importantly, DLK1/MEG3 demonstrated disturbed methylation in ART-PGD samples compared to controls and this was associated with altered HERV-K methylation. No differences were detected in p57(KIP2) and IGF2/H19 methylation patterns between ART-PGD and naturally conceived controls. Using bioinformatics, we found that while the genome surrounding the p57(KIP2) and IGF2/H19 genes differentially methylated regions had low coverage in transposable element (TE) sequences, the respective one of DLK1/MEG3 was characterized by an almost 2-fold higher coverage. Moreover, our analyses revealed the presence of KAP1-binding sites residing within retrotransposon sequences only in the DLK1/MEG3 locus. Our results demonstrate that altered HERV-K methylation in the ART-PGD conceptuses is correlated with abnormal imprinting of the DLK1/MEG3 locus and suggest that TEs may be affecting the establishment of genomic imprinting under stress conditions. PMID:23786541
Dimitriadou, Eftychia; Noutsopoulos, Dimitrios; Markopoulos, Georgios; Vlaikou, Angeliki-Maria; Mantziou, Stefania; Traeger-Synodinos, Joanne; Kanavakis, Emmanouel; Chrousos, George P; Tzavaras, Theodore; Syrrou, Maria
Setting up equine embryo gender determination by preimplantation genetic diagnosis in a commercial embryo transfer program.
Preimplantation genetic diagnosis (PGD) allows identifying genetic traits in early embryos. Because in some equine breeds, like Polo Argentino, females are preferred to males for competition, PGD can be used to determine the gender of the embryo before transfer and thus allow the production of only female pregnancies. This procedure could have a great impact on commercial embryo production programs. The present study was conducted to adapt gender selection by PGD to a large-scale equine embryo transfer program. To achieve this, we studied (i) the effect on pregnancy rates of holding biopsied embryos for 7 to 10 hours in holding medium at 32 �C before transfer, (ii) the effect on pregnancy rates of using embryos of different sizes for biopsy, and (iii) the efficiency of amplification by heating biopsies before polymerase chain reaction. Equine embryos were classified by size (?300, 300-1000, and >1000 ?m), biopsied, and transferred 1 to 2 or 7 to 10 hours after flushing. Some of the biopsy samples obtained were incubated for 10 minutes at 95 �C and the rest remained untreated. Pregnancy rates were recorded at 25 days of gestation; fetal gender was determined using ultrasonography and compared with PGD results. Holding biopsied embryos for 7 to 10 hours before transfer produced pregnancy rates similar to those for biopsied embryos transferred within 2 hours (63% and 57%, respectively). These results did not differ from pregnancy rates of nonbiopsied embryos undergoing the same holding times (50% for 7-10 hours and 63% for 1-2 hours). Pregnancy rates for biopsied and nonbiopsied embryos did not differ between size groups or between biopsied and nonbiopsied embryos within the same size group (P > 0.05). Incubating biopsy samples for 10 minutes at 95 �C before polymerase chain reaction significantly increased the diagnosis rate (78.5% vs. 45.5% for treated and nontreated biopsy samples respectively). Gender determination using incubated biopsy samples matched the results obtained using ultrasonography in all pregnancies assessed (11/11, 100%); untreated biopsy samples were correctly diagnosed in 36 of 41 assessed pregnancies (87.8%), although the difference between treated and untreated biopsy samples was not significant. Our results demonstrated that biopsied embryos can remain in holding medium before being transferred, until gender diagnosis by PGD is complete (7-10 hours), without affecting pregnancy rates. This simplifies the management of an embryo transfer program willing to incorporate PGD for gender selection, by transferring only embryos of the desired sex. Embryo biopsy can be performed in a clinical setting on embryos of different sizes, without affecting their viability. Additionally, we showed that pretreating biopsy samples with a short incubation at 95 �C improved the overall efficiency of embryo sex determination. PMID:24439164
Herrera, C; Morikawa, M I; Bello, M B; von Meyeren, M; Centeno, J Eusebio; Dufourq, P; Martinez, M M; Llorente, J
Preimplantation diagnosis for single gene disorders.
Preimplantation genetic diagnosis (PGD) allows patients who are carriers or who are affected by genetic diseases to select unaffected embryos for transfer before becoming pregnant. The practice of PGD is evolving with rapid advances in technology and biopsy methods. Testing for a specific gene mutation can be performed in combination with 24-chromosome aneuploidy screening. Several unique applications of PGD are reviewed, including exclusion diagnosis for couples from Huntington disease families, testing for fragile X premutations, and human leukocyte antigen matching for stem cell donor siblings. Although PGD for single gene mutations allows patients to gain information about their embryos and perhaps avoid a difficult decision about whether or not to terminate an ongoing pregnancy, this technique also provides for much ethical debate encompassing the well-being of the prospective couple, embryo, child, and people in the community affected by the diseases being screened. PMID:24515905
Berger, Victoria K; Baker, Valerie L
Preimplantation Genetic Diagnosis for Aneuploidy and Translocations Using Array Comparative Genomic Hybridization
At least 50% of human embryos are abnormal, and that increases to 80% in women 40 years or older. These abnormalities result in low implantation rates in embryos transferred during in vitro fertilization procedures, from 30% in women <35 years to 6% in women 40 years or older. Thus selecting normal embryos for transfer should improve pregnancy results. The genetic analysis of embryos is called Preimplantation Genetic Diagnosis (PGD) and for chromosome analysis it was first performed using FISH with up to 12 probes analyzed simultaneously on single cells. However, suboptimal utilization of the technique and the complexity of fixing single cells produced conflicting results. PGD has been invigorated by the introduction of microarray testing which allows for the analysis of all 24 chromosome types in one test, without the need of cell fixation, and with staggering redundancy, making the test much more robust and reliable. Recent data published and presented at scientific meetings has been suggestive of increased implantation rates and pregnancy rates following microarray testing, improvements in outcome that have been predicted for quite some time. By using markers that cover most of the genome, not only aneuploidy can be detected in single cells but also translocations. Our validation results indicate that array CGH has a 6Mb resolution in single cells, and thus the majority of translocations can be analyzed since this is also the limit of karyotyping. Even for translocations with smaller exchanged fragments, provided that three out of the four fragments are above 6Mb, the translocation can be detected.
Munne, Santiago
Increased IVF pregnancy rates after microarray preimplantation genetic diagnosis due to parental translocations.
We successfully performed preimplantation genetic diagnosis (PGD) and simultaneous preimplantation genetic screening (PGS) using single nucleotide polymorphism (SNP) microarrays for couples with balanced chromosome rearrangements in China. A total of 428 molecular karyotypes were diagnosed from 62 couples undergoing 68 in vitro fertilization (IVF) cycles. Of these, 48.1% of the embryos were chromosomally normal without translocation errors or aneuploidy. Of the 428 total embryos, 18.0% embryos were euploid, but were imbalanced due to the transmission of single translocation chromosome derivatives. A total of 6.5% of the embryos had chromosome abnormalities involving the parental chromosome aberration and other chromosomes aneuploidies. Significantly, 27.4% of the embryos were normal/balanced for the rearranged chromosomes, but were abnormal due to aneuploidy affecting other chromosomes. When evaluated on a per IVF cycle basis, 84% of the cycles had at least one chromosomally normal embryo available for uterine transfer. The clinical pregnancy rate per IVF cycle was 54%. Diagnosing genomically balanced embryos through 24 chromosome SNP microarray PGD/PGS, rather than minimally targeted fluorescence in situ hybridization (FISH), is a promising strategy to maximize the pregnancy potential of patients with known parental chromosomal translocations. Moreover, this is the first study to report the clinical application of SNP arrays to screen all 24 chromosome pairs of blastomeres and trophectoderm cells from patients carrying reciprocal translocations in China. PMID:24377704
Li, Gang; Jin, Haixia; Xin, Zhimin; Su, Yingchun; Brezina, Paul R; Benner, Andrew T; Kearns, William G; Sun, Yingpu
Ethics of PGD: thoughts on the consequences of typing HLA in embryos.
As with so many fields of study associated with assisted human reproduction, many ethical issues are raised by the practice of preimplantation diagnosis of inherited disease (PGD). Some are part and parcel of assisted conception, e.g.the rights of human embryos in vitro and of embryologists to establish them, carry out research and discard them. Others unique to clinical PGD were discussed at an earlier meeting on PGD (Edwards et al., 2003). Recent developments in PGD are discussed briefly in this Commentary, especially the ethics of designer babies. PMID:15333255
Edwards, R G
Successful PGD cycles for mosaic Robertsonian translocation carriers provide insights into the mechanism of formation of the derivative chromosomes.
Preimplantation genetic diagnosis (PGD) has been carried out for two couples with different mosaic Robertsonian translocations. Two PGD cycles for a mosaic 13;13 homologous Robertsonian translocation carrier resulted in the birth of a healthy child in each cycle, illustrating the importance of scanning G-banded preparations from homologous Robertsonian carriers for the presence of a normal cell line. One couple was referred for PGD because the male partner carried a mosaic 14;15 Robertsonian translocation with a normal cell line. A single PGD cycle resulted in the birth of a healthy child. Follow-up studies and extended FISH analysis of the carrier's lymphocytes detected three cell lines, two carrying different 14;15 Robertsonian chromosomes and one normal cell line. The two 14;15 Robertsonian chromosomes had different breakpoints in the proximal short arm regions. We suggest that the presence of the D15Z1 polymorphism on the short arm of one chromosome 14 mediated the post-zygotic formation of the two different Robertsonian chromosomes. PMID:23401053
Bint, Susan M; Scriven, Paul N; Ogilvie, Caroline Mackie
Validating a rapid, real-time, PCR-based direct mutation detection assay for preimplantation genetic diagnosis.
Although co-amplification of polymorphic microsatellite markers is the current gold standard for preimplantation genetic diagnosis (PGD) of single-gene disorders (SGD), this approach can be hampered by the lack of availability of informative markers. We recently (2011) devised a novel in-house assay for PGD of aromatic l-amino acid decarboxylase deficiency, based on an amplification refractory mutation system and quantitative PCR (ARMS-qPCR). The objective of the present study was to verify ARMS-qPCR in a cohort of 20 PGD cycles with a diverse group of SGDs (15 couples at risk for 10 SGDs). Day-3 cleavage-stage embryos were subjected to biopsy and genotyping, followed by fresh embryo transfer (FET). The diagnostic rate was 82.9%; unaffected live births were achieved in 9 of 20 FET cycles (45%), with only one false negative (among 54 transferred embryos). Overall, the ARMS-qPCR had frequent allele-dropout (ADO), rendering it inappropriate as the sole diagnostic method (despite a favorable live-birth rate). Regardless, it has the potential to complement the current gold-standard methodology, especially when trophectoderm biopsy becomes a preferred option and genotyping needs to be timely enough to enable FET. PMID:25034658
Chen, Hsin-Fu; Chang, Shun-Ping; Wu, Sheng-Hai; Lin, Wen-Hsiang; Lee, Yi-Chung; Ni, Yen-Hsuan; Chen, Chi-An; Ma, Gwo-Chin; Ginsberg, Norman A; You, En-Min; Tsai, Feng-Po; Chen, Ming
PGD gender selection for non-Mendelian disorders with unequal sex incidence.
Preimplantation genetic diagnosis (PGD) was originally developed for couples whose potential offspring were at risk of severe Mendelian disorders, but has since been extended to other indications. One possible use of PGD is to perform gender selection for couples whose offspring are at increased risk of disorders that do not follow Mendelian inheritance, but which are substantially more common in one sex than another (unequal sex incidence). Here, we examine the clinical and ethical issues to be considered prior to offering PGD gender selection to reduce the risk of a child being affected by a non-Mendelian condition with unequal sex incidence. Factors to be considered include: the risk that a child of either sex will be affected by the condition; the overall reduction in risk provided by gender selection and the potential harms of the procedure. Consideration should also be given to the interests of the family and the child to be born, the seriousness of the condition and the couple's procreative autonomy. To illustrate these issues we use the example of autism, a non-Mendelian disorder that is considerably more common in males than in females. PMID:18222917
Amor, David J; Cameron, Carolyn
Ethics of PGD: thoughts on the consequences of typing HLA in embryos
As with so many fields of study associated with assisted human reproduction, many ethical issues are raised by the practice of preimplantation diagnosis of inherited disease (PGD). Some are part and parcel of assisted conception, e.g. the rights of human embryos in vitro and of embryologists to establish them, carry out research and discard them. Others unique to clinical PGD
RG Edwards
[Genetic diagnosis of phaeochromocytomas and paragangliomas].
Up to 30% of phaeochromocytomas and paragangliomas occur in the context of inherited tumor syndromes. Familial history and clinical presentation have to be strongly detailed to guide genetic testing. The identification of a genetic predisposition in a patient with phaeochromocytoma or paraganglioma has a positive impact in terms of medical care and follow-up for the proband and allows genetic testing in apparently asymptomatic family members. Two clusters of genes are described depending on their implication in the pathogenesis of inherited tumors. An algorithm for the genetic diagnosis of phaeochromocytomas and paragangliomas is proposed by The French network of oncogenetic laboratories. These recommendations will probably change with the identification of new predisposition genes and the development of new sequencing technologies.Genetic testing is prescribed by a specialist, as part of a cancer genetics specialist consultation in endocrine tumors. The psychological support is essential throughout the family survey. PMID:24612707
Cardot-Bauters, Catherine; Ainaou�, Malika; Coppin, Lucie; Pigny, Pascal
Preimplantation genetic screening: do we need a degree of caution?
Preimplantation genetic diagnosis (PGD) is a form of very early prenatal diagnosis. The technique combines assisted reproductive technology with molecular and cyto-genetics to allow the identification of abnormalities in embryos prior to implantation. Advancing maternal age is associated with a reduction in oocyte quality due to an increase in meiotic errors, possibly compounded by poor follicular vascularisation, oxidative damage and
Stuart Lavery
Plasmonic DNA: Towards Genetic Diagnosis Chips
The present paper summarizes some of our activities in the field of plasmonic DNA and genetic diagnosis, presenting our system\\u000a and its capabilities before showing data related to the design and use of functionalized biochips of increasing complexity\\u000a along with various experimental hybridization conditions, including solutions containing one type of purified synthetic short\\u000a oligonucleotides or PCR-amplified DNA samples from patients.
J�r�me Hottin; Julien Moreau; Gis�le Roger; Jolanda Spadavecchia; Marie-Claude Millot; Michel Goossens; Michael Canva
Genetic Issues in the Diagnosis of Dystonias
Dystonias are heterogeneous hyperkinetic movement disorders characterized by involuntary muscle contractions which result in twisting and repetitive movements and abnormal postures. Several causative genes have been identified, but their genetic bases still remain elusive. Primary Torsion Dystonias (PTDs), in which dystonia is the only clinical sign, can be inherited in a monogenic fashion, and many genes and loci have been identified for autosomal dominant (DYT1/TOR1A; DYT6/THAP1; DYT4/TUBB4a; DYT7; DYT13; DYT21; DYT23/CIZ1; DYT24/ANO3; DYT25/GNAL) and recessive (DYT2; DYT17) forms. However most sporadic cases, especially those with late-onset, are likely multifactorial, with genetic and environmental factors interplaying to reach a threshold of disease. At present, genetic counseling of dystonia patients remains a difficult task. Recently non-motor clinical findings in dystonias, new highlights in the pathophysiology of the disease, and the availability of high-throughput genome-wide techniques are proving useful tools to better understand the complexity of PTD genetics. We briefly review the genetic basis of the most common forms of hereditary PTDs, and discuss relevant issues related to molecular diagnosis and genetic counseling.
Petrucci, Simona; Valente, Enza Maria
Genetic diagnosis before the eighth gestational week.
Transabdominal chorionic villus sampling (CVS) by a freehand, ultrasound-guided technique was offered to 210 high-genetic-risk women at 6-7 weeks' gestation. It was carried out in 201 cases and postponed in nine cases (4.3%). Sampling was successful in 86 and 100% of cases after the first and the second needle insertions, respectively. Chorionic tissue specimens weighed at least 20 mg in 86% of cases, and only 2% were below 10 mg. Early complications were present in 7.9% of cases, apparently without any adverse effect on maternal or fetal outcome. The rate of fetal loss was 3.5%. Genetic diagnosis was concluded in 1-3 days by rapid diagnostic methods. Although more extensive laboratory and clinical experience is necessary to evaluate adequately the safety of early transabdominal CVS, it may be advantageous to offer this technique to certain high-genetic-risk patients. The availability of genetic diagnosis before the eighth week makes clinical abortion by antiprogestins and prostaglandins a viable option in cases of affected embryos. PMID:1988902
Brambati, B; Tului, L; Simoni, G; Travi, M
The embryo as moral work object: PGD/IVF staff views and experiences.
We report on one aspect of a study that explored the views and experiences of practitioners and scientists on social, ethical and clinical dilemmas encountered when working in the field of preimplantation genetic diagnosis (PGD) for serious genetic disorders. The study produced an ethnography based on observation, interviews and ethics discussion groups with staff from two PGD/IVF Units in the UK. We focus here on staff perceptions of work with embryos that entails disposing of 'affected' or 'spare' embryos or using them for research. A variety of views were expressed on the 'embryo question' in contrast to polarised media debates. We argue that the prevailing policy acceptance of destroying affected embryos, and allowing research on embryos up to 14 days leaves some staff with rarely reported, ambivalent feelings. Staff views are under-researched in this area and we focus on how they may reconcile their personal moral views with the ethical framework in their field. Staff construct embryos in a variety of ways as 'moral work objects'. This allows them to shift attention between micro-level and overarching institutional work goals, building on Casper's concept of 'work objects' and focusing on negotiation of the social order in a morally contested field. PMID:18444955
Ehrich, Kathryn; Williams, Clare; Farsides, Bobbie
Preimplantation genetic diagnosis of inherited disease.
Research on diagnosis of inherited disease in human embryo before implantation was initiated to help those couples who would prefer to select embryos at this stage rather than during pregnancy. Following in vitro fertilization (IVF), one to two cells were removed from 3 day cleavage stage embryo and cells were analysed for genetic defects. Embryos diagnosed as unaffected were returned to the uterus and thus the resulting pregnancies were assured to be normal. First babies born after the preimplantation diagnosis were using DNA amplification of Y-linked sequences by PCR to avoid X-linked disease. Several pregnancies were obtained by identifying sex of embryos using dual fluorescent in situ hybridization (FISH) with fluorochrome labelled DNA sequences specific for X- and Y-chromosomes to interphase nuclei. Development of single cell PCR for single gene defects led to diagnose several genetic disorders. Preimplantation diagnosis was successfully achieved for predominant delta 508 deletion causing cystic fibrosis, and pregnancies were also diagnosed for Lesch-Nyhan syndrome, Tay-Sachs and Duchenne muscular dystrophy. PMID:9246906
Ao, A
Comparison of whole genome amplification and nested-PCR methods for preimplantation genetic diagnosis for BRCA1 gene mutation on unfertilized oocytes-a pilot study
Background Preimplantation genetic diagnosis (PGD) remains nowadays a valid alternative for couples at high-risk of having a child with a genetic disease and for women older than 37�40�years with the high risk of chromosomal aneuploidies in the embryos. However the use of PGD for high penetrance recessive, dominant and X-liked disorders occurring in early life is documented, debate exists regarding its appropriateness in lower penetrance and late-onset cancer susceptibility syndromes. The data regarding the efficacy of different molecular techniques used in PGD are still lacking. We therefore sought to assess the different molecular techniques used in PGD for detecting three most frequent BRCA1 gene mutations: 5382insC, 185delAG and C61G. Methods Anonymous donors of the oocytes and control healthy blood samples were extracted and analyzed in the Fertility and Reproductive Center Invicta in Gdansk. Preimplantation genetic diagnosis for the most frequent mutations: 185delAG, 5382insC, C61G in BRCA 1 gene was carried out on single, unfertilized oocytes, in metaphase of second meiotic division, not qualified to IVF. Positive mutation controls were represented by cell lines from the Coriell Institute for Medical Research: GM14090 (185delAG), GM14097 (C61G), GM13715 (5382insC). Results Repeatability of the results acquired from the WGA analysis for the mutation 5382insC was 38%. The repeatability of the nested-PCR analysis in the second round of the amplification was labile for the mutation 5382insC and 185delAG and was ranged from 47% to 57%. However, the repeatability for the mutation C61G was 100%. Conclusions Our results suggest that the nested-PCR technique remains more sensitive and specific method as compared to WGA. WGA performed on the single cells did not reflect expected results. The repeatability of the WGA methodology remains questionable, and any analysis attempt does not guarantee reliable results. Further evaluation is strongly needed to propose the most accurate molecular technique used in PGD for detecting three most frequent BRCA1 gene mutations: 5382insC, 185delAG and C61G.
Objective: Embryonic chromosomal abnormality is one of the main reasons for in vitro fertilization (IVF) failure. This study aimed at evaluating the value of Fluorescence in-situ Hybridization (FISH)-based Preimplantation Ge- netic Diagnosis (PGD) in screening for embryonic chromosomal abnormality to increase the successful rate of IVF. Method: Ten couples, four with high risk of chromosomal abnormality and six infertile couples,
YE Ying-hui; XU Chen-ming; QIAN Yu-li
Successful pregnancy outcome after in vitro fertilisation following Pre-implantation Genetic Diagnosis/Polymerase Chain Reaction screening for single gene disorder (sickle cell anaemia) before embryo transfer: The clinical experience of an in vitro fertilisation clinic in Nigeria
A couple, both carriers of the sickle cell anaemia trait (Genotype HbAS) with an offspring already affected with the genetic disease underwent a Pre-implantation Genetic Diagnosis/Polymerase Chain Reaction screening of biopsied blastomeres. DNA analysis of single blastomeres was carried out to find out indicated a viable intra-uterine pregnancy with embryos which carried the sickle cell mutation, which resulted in a livebirth (HbAS). PGD/PCR in combination with IVF appears to be the most suitable treatment plan for patients who are at a higher risk of reproducing offspring affected with inheritable genetic diseases.
Okeke, Chizara; Ailoje-Ibru, Kemi; Olukoya, Kemi; Ogbeche, Rose; Adewusi, Abiola; Iloabachie, Ebele; Ashiru, Oladapo
Identification of a Novel Single Nucleotide Polymorphism of HADHA Gene at a Referred Primer-binding Site During Pre-diagnostic Tests for Preimplantation Genetic Diagnosis
The pre-diagnostic test for preimplantation genetic diagnosis (PGD) of long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency was performed by polymerase chain reaction (PCR) and direct sequencing for hydroxyacyl-Coenzyme A dehydrogenase/3-ketoacyl-Coenzyme A thiolase/enoyl-Coenzyme A hydratase (HADHA) gene. We obtained unexpected genotyping results of HADHA gene by allele drop-out in the analysis of patients' genomic DNA samples with a referred PCR primer set. Upon further analysis with a re-designed primer set, we found a novel single nucleotide polymorphism (SNP) at the referred primer-binding site in the normal allele of HADHA gene (NT_022184, 5233296 a>t). We found that the frequency of this novel SNP was 0.064 in Korean population. Pre-diagnostic test using single lymphocytes and clinical PGD were successfully performed with the re-designed primer set. Nineteen embryos (95.0%) among 20 were successfully diagnosed to 5 homozygous mutated, 8 heterozygous carrier and 6 wild type. Among 6 normal embryos, well developed and selected 4 embryos were transferred into the mother's uterus, but a pregnancy was not achieved. We proposed that an unknown SNP at primer-binding sites would be a major cause of allele drop-out in the PGD for single gene disorder.
Lee, Hyoung-Song; Choi, Hye Won; Lim, Chun Kyu; Koong, Mi Kyoung; Kang, Inn Soo; Yoo, Han-Wook; Choi, Jin-Ho
Regulating preimplantation genetic diagnosis: a criminal model versus a professional model.
This article examines a criminal and professional approach to the regulation of preimplantation diagnosis (PGD) in the two Australian States of Victoria and New South Wales. Under the Assisted Reproductive Treatment Act 2008 (Vic), Victorian medical practitioners face criminal sanctions if they ignore legal requirements. The criminal sanctions do not apply directly to patients, but those seeking PGD treatment have to satisfy guiding legislative principles, statutory rules and the controversial new "presumption against treatment" hurdle. On the other hand, the Assisted Reproductive Technology Act 2008 (NSW) does not specifically address PGD and medical practitioners in New South Wales are not subject to criminal sanctions but must follow the National Health and Medical Research Council Guidelines. As far as patients in New South Wales are concerned, PGD is essentially a medical procedure. In both Victoria and New South Wales, PGD practice is relatively liberal compared to that in many other countries, although the Victorian approach is clearly the more restrictive model of regulation with the threat of criminal sanctions overriding the medical practitioner's ethical duty to act in the best interests of a patient. PMID:20169804
Petersen, Kerry
Use of preimplantation genetic diagnosis for serious adult onset conditions: a committee opinion.
PGD for adult-onset conditions is ethically justified when the condition is serious and no safe, effective interventions are available. It is ethically allowed for conditions of lesser severity or penetrance. The Committee strongly recommends that an experienced genetic counselor play a major role in counseling patients considering such procedures. PMID:23477677
Preimplantation genetic diagnosis to improve pregnancy outcomes in subfertility.
Pre-implantation genetic diagnosis provides prenatal genetic diagnosis before implantation, thus allowing detection of chromosomal abnormalities and their exclusion from embryo transfer in assisted reproductive technologies. Polar body, blastomere or trophectoderm can each be used to obtain requisite genetic or embryonic DNA. Pre-implantation genetic diagnosis for excluding unbalanced translocations is well accepted, and pre-implantation genetic diagnosis aneuploidy testing to avoid repeated pregnancy losses in couples having recurrent aneuploidy is efficacious in reducing miscarriages. Controversy remains about whether pre-implantation genetic diagnosis aneuploidy testing improves take home pregnancy rates, for which reason adherence to specific indications is recommended while the issue is being adjudicated. Current recommendations are for obligatory 24 chromosome testing, most readily using array comparative genome hybridisation. PMID:22749544
Simpson, Joe Leigh
Hyperinsulinaemic hypoglycaemia: genetic mechanisms, diagnosis and management.
Hyperinsulinaemic hypoglycaemia (HH) is due to the unregulated secretion of insulin from pancreatic ?-cells. A rapid diagnosis and appropriate management of these patients is essential to prevent the potentially associated complications like epilepsy, cerebral palsy and neurological impairment. The molecular basis of HH involves defects in key genes (ABCC8, KCNJ11, GLUD1, GCK, HADH, SLC16A1, HNF4A and UCP2) which regulate insulin secretion. The most severe forms of HH are due to loss of function mutations in ABCC8/KCNJ11 which encode the SUR1 and KIR6.2 components respectively of the pancreatic ?-cell K(ATP) channel. At a histological level there are two major forms (diffuse and focal) each with a different genetic aetiology. The diffuse form is inherited in an autosomal recessive (or dominant) manner whereas the focal form is sporadic in inheritance and is localised to a small region of the pancreas. The focal form can now be accurately localised pre-operatively using a specialised positron emission tomography scan with the isotope Fluroine-18L-3, 4-dihydroxyphenyalanine (18F-DOPA-PET). Focal lesionectomy can provide cure from the hypoglycaemia. However the diffuse form is managed medically or by near total pancreatectomy (with high risk of diabetes mellitus). Recent advances in molecular genetics, imaging with 18F-DOPA-PET/CT and novel surgical techniques have changed the clinical approach to patients with HH. PMID:22231386
Senniappan, Senthil; Shanti, Balasubramaniam; James, Chela; Hussain, Khalid
Successful birth with preimplantation genetic diagnosis using single-cell allele-specific PCR and sequencing in a woman with hypochondroplasia due to FGFR3 mutation (c.1620C>A, p.N540K)
Hypochondroplasia (HCH) is an autosomal dominant inherited skeletal dysplasia, usually caused by a heterozygous mutation in the fibroblast growth factor receptor 3 gene (FGFR3). A 27-year-old HCH woman with a history of two consecutive abortions of HCH-affected fetuses visited our clinic for preimplantation genetic diagnosis (PGD). We confirmed the mutation in the proband (FGFR3:c.1620C>A, p.N540K), and established a nested allele-specific PCR and sequence analysis for PGD using single lymphocyte cells. We performed this molecular genetic analysis to detect the presence of mutation among 20 blastomeres from 18 different embryos, and selected 9 embryos with the wild-type sequence (FGFR3:c.1620C). A successful pregnancy was achieved through a frozen-thawed cycle and resulted in the full-term birth of a normal neonate. To the best of our knowledge, this is the first report of a successful pregnancy and birth using single-cell allele-specific PCR and sequencing for PGD in an HCH patient.
Park, Kyung Eui; Kim, Sung Ah; Kang, Moon Joo; Kim, Hee Sun; Cho, Sung Im; Yoo, Kyoung Won; Kim, So Yeon; Lee, Hye Jun; Oh, Sun Kyung; Seong, Moon-Woo; Ku, Seung-Yup; Jun, Jong Kwan; Park, Sung Sup; Moon, Shin Yong
Assessment of the risk of blastomere biopsy during preimplantation genetic diagnosis in a mouse model: reducing female ovary function with an increase in age by proteomics method.
Preimplantation genetic diagnosis (PGD) is important for screening genetic and chromosome mutations in embryos so that the efficiency of assisted reproductive treatment can be increased and birth defects can be decreased; however, some studies have reported a risk from this technology as well as other assisted reproductive technologies. We have developed a blastomere biopsy mouse model to assess the potential effects of blastomere biopsy that was one key procedure in PGD on the fertility of female mice at different ages. We showed that female fertility was decreased in the biopsied mouse model with an increase in age. Moreover, the ovarian weight, serum hormone levels, and the number of primordial, primary, preantral, and antral stage follicles were also decreased in the middle-aged biopsied mouse model. To elucidate the underlying molecular mechanism, we did proteomics analysis on ovarian tissues from puberty biopsied and nonbiopsied mice of the 23 differentially expressed proteins that were screened for in both groups, 3 proteins (PSMB8, ALDH1A1, and HSPA4) were selected and identified by Western blotting and quantitative RT-PCR methods, which showed the 3 proteins to regulate 12 cellular pathways. Furthermore, these three proteins were shown to be located in ovarian tissues, and the dynamic changes of expression profiling in middle-aged biopsied and nonbiopsied mice were demonstrated. The present study showed that blastomere biopsy technology impairs fertility when mice are middle-aged, which possibly resulted in abnormal expression profiling of PSMB8, ALDH1A1, and HSPA4 proteins. Thus, additional studies should be performed to assess the overall risk of blastomere biopsies during PGD procedures. PMID:24156634
Yu, Yang; Zhao, Yue; Li, Rong; Li, Li; Zhao, Hongcui; Li, Min; Sha, Jiahao; Zhou, Qi; Qiao, Jie
Preimplantation genetic diagnosis: strategies and surprises
Several inherited diseases can now be diagnosed by genetic analysis of single cells biopsied from human eggs and preimplantation embryos following in vitro fertilization (IVF). �At risk� couples can, therefore, have only unaffected embryos replaced in the uterus and avoid the possibility of terminating a pregnancy that might only be diagnosed as affected later in gestation. Single-cell genetic analysis has
Alan H. Handyside; Joy D. A. Delhanty
Conversion and non-conversion approach to preimplantation diagnosis for chromosomal rearrangements in 475 cycles
Due to the limitations of preimplantation genetic diagnosis (PGD) for chromosomal rearrangements by interphase fluorescent in-situ hybridization (FISH) analysis, a method for obtaining chromosomes from single blastomeres was introduced by their fusion with enucleated or intact mouse zygotes, followed by FISH analysis of the resulting heterokaryons. Although this allowed a significant improvement in the accuracy of testing of both maternally
Anver Kuliev; Jeanine Cieslak Janzen; Zev Zlatopolsky; Irina Kirillova; Yury Ilkevitch; Yury Verlinsky
Lactose intolerance: diagnosis, genetic, and clinical factors
Most people are born with the ability to digest lactose, the major carbohydrate in milk and the main source of nutrition until weaning. Approximately 75% of the world�s population loses this ability at some point, while others can digest lactose into adulthood. This review discusses the lactase-persistence alleles that have arisen in different populations around the world, diagnosis of lactose intolerance, and its symptomatology and management.
Mattar, Rejane; de Campos Mazo, Daniel Ferraz; Carrilho, Flair Jose
Parents' experiences of receiving their child's genetic diagnosis: A qualitative study to inform clinical genetics practice.
Little is currently known about how parents experience the medical genetics appointment at which their child receives a genetic diagnosis. We conducted semi-structured in-person interviews with 13 parents of 10 index children to explore their experience in the medical genetics appointment in which they received their child's genetic diagnosis. Guided by grounded theory, we used a constant comparative approach to data analysis. Transcribed interviews were coded and sorted, and thematic categories identified. Sixty-one and a half percent of parents experienced the diagnosis session as negative, 23% felt the experience was positive, and 15.5% were ambivalent. Receiving emotional support, an outline of the follow-up plans, and messages of hope and perspective during the session seemed to positively influence parents' experience, while feeling that their role was as a passive receiver of information and the use of difficult medical terminology negatively influenced parents' overall experience. Parental preparedness for the information, and the parents' emotional reaction to the diagnosis were also factors that influenced the parental experience. Few participants understood the role of the genetic counselor. Our results provide in-depth insight into the parental experience of the pediatric medical genetics diagnosis session. We propose a mechanism through which parental experience shapes their perception of the medical genetics session. � 2014 Wiley Periodicals, Inc. PMID:24706543
Ashtiani, Setareh; Makela, Nancy; Carrion, Prescilla; Austin, Jehannine
The borderline diagnosis II: biology, genetics, and clinical course
In Part I of this three-part article, consideration of the core features of BPD psychopathology, of comorbidity with Axis I disorders, and of underlying personality trait structure suggested that the borderline diagnosis might be productively studied from the perspective of dimensions of trait expression, in addition to that of the category itself. In Part II, we review the biology, genetics,
Andrew E Skodol; Larry J Siever; W. John Livesley; John G Gunderson; Bruce Pfohl; Thomas A Widiger
Genetics on stage: Public engagement in health policy development on preimplantation genetic diagnosis
Arts-based approaches to public engagement offer unique advantages over traditional methods of consultation. Here we describe and assess our use of theatre as a method of public engagement in the development of health policy on preimplantation genetic diagnosis, a controversial method for selecting the genetic characteristics of embryos created through in vitro fertilization. Funding from the Canadian Institutes for Health
Susan M. Cox; Magdalena Kazubowski-Houston; Jeff Nisker
Genetic testing and early diagnosis and intervention: boon or burden?
The possibility of early diagnosis and intervention is radically changed by the advent of genetic testing. The recent report of the Nuffield Council on Bioethics is timely and helpful. I have suggested, that not only the severity of the disability indicated by genetic information, and the accuracy of the data, ought to govern the approach to the implementation of screening for genetic disorders. In addition, assessment of the value of the information to those involved should be considered. The efficacy of the available therapeutic measures, combined with the prognostic data are important indices of the value of the information. These measures fall into three categories and thus indicate that three different courses of intervention may be appropriate. Three approaches to diagnosis and intervention are then outlined, drawing on the experience of various clinical initiatives.
Hepburn, E R
Hyperinsulinaemic Hypoglycaemia: Genetic Mechanisms, Diagnosis and Management
Hyperinsulinaemic hypoglycaemia (HH) is characterized by unregulated insulin secretion from pancreatic ?-cells. Untreated hypoglycaemia in infants can lead to seizures, developmental delay, and subsequent permanent brain injury. Early identification and meticulous managementof these patients is vital to prevent neurological insult. Mutations in eight different genes (ABCC8, KCNJ11, GLUD1, CGK, HADH, SLC16A1, HNF4A and UCP2) have been identified to date in patients with congenital forms of hyperinsulinism (CHI). The most severe forms of CHI are due to mutations in ABCC8 and KCJN11, which encode the two components of pancreatic ?-cell ATP-sensitive potassium channel. Recent advancement in understanding the genetic aetiology, histological characterisation into focal and diffuse variety combined with improved imaging (such as fluorine 18 L-3, 4-dihydroxyphenylalanine positron emission tomography 18F-DOPA-PET scanning) and laparoscopic surgical techniques have greatly improved management. In adults, HH can be due to an insulinoma, pancreatogenous hypoglycaemic syndrome, post gastric-bypass surgery for morbid obesity as well as to mutations in insulin receptor gene. This review provides an overview of the molecular basis of CHI and outlines the clinical presentation, diagnostic criteria, and management of these patients. Conflict of interest:None declared.
Mohamed, Zainaba; Arya, Ved Bhushan; Hussain, Khalid
Genetic diagnosis of neuroacanthocytosis disorders using exome sequencing.
Neuroacanthocytoses are neurodegenerative disorders marked by phenotypic and genetic heterogeneity. There are several associated genetic loci, and many defects, including gene deletions and insertions, and missense, nonsense, and splicing mutations, have been found spread over hundreds of kilobases of genomic DNA. In some cases, specific diagnosis is unclear, particularly in the early stages of disease or when there is an atypical presentation. Determination of the precise genetic defect allows assignment of the diagnosis and permits carrier detection and genetic counseling. The objective of this report was to utilize exome sequencing for genetic diagnosis in the neuroacanthocytosis syndromes. Genomic DNA from 2 patients with clinical features of chorea-acanthocytosis was subjected to targeted exon capture. Captured DNA was subjected to ultrahigh throughput next-generation sequencing. Sequencing data were assembled, filtered against known human variant genetic databases, and results were analyzed. Both patients were compound heterozygotes for mutations in the VPS13A gene, the gene associated with chorea-acanthocytosis. Patient 1 had a 4-bp deletion that removes the 5' donor splice site of exon 58 and a nucleotide substitution that disrupts the 5' donor splice site of exon 70. Patient 2 had a dinucleotide deletion in exon 16 and a dinucleotide insertion in exon 33. No mutations were identified in the XK, PANK2, or JPH3 gene loci. Exome sequencing is a valuable diagnostic tool in the neuroacanthocytosis syndromes. These studies may provide a better understanding of the function of the associated proteins and provide insight into the pathogenesis of these disorders. PMID:22038564
Walker, Ruth H; Schulz, Vincent P; Tikhonova, Irina R; Mahajan, Milind C; Mane, Shrikant; Arroyo Muniz, Maritza; Gallagher, Patrick G
Role of molecular genetics in hemophilia: from diagnosis to therapy.
Despite significant advancements, state-of-the-art care remains inaccessible to patients with hemophilia, especially those from developing countries. Thus, innovative approaches in the management of this condition are needed to improve their quality of life. In this context, genetic studies in hemophilia have contributed to the better understanding of its biology, the detection of carriers, and prenatal diagnosis, and even fostering newer therapeutic strategies. This article reviews the applications of molecular genetics in hemophilia, in general, and how such techniques can be useful for optimizing patient care, in particular. PMID:22314605
Jayandharan, Giridhara Rao; Srivastava, Arun; Srivastava, Alok
Prospect of preimplantation genetic diagnosis for heritable mitochondrial DNA diseases
To perform preimplantation genetic diagnosis for women carrying heteroplasmic mitochondrial DNA (mtDNA) mutations, it is necessary to ensure that the proportion of mutant mtDNA diagnosed in the biopsied cell gives an accurate indication of the mutant load in the remaining embryo. A heteroplasmic mouse model, carrying NZB and BALB mtDNA genotypes, was used to study the relative proportions of each
Nicola L. Dean; Brendan J. Battersby; Asangla Ao; Roger G. Gosden; Seang LinTan; Eric A. Shoubridge
[Genetic diagnosis and molecular pathology of inherited neuropathy].
Recent advances in genetic analysis technology have enabled a surprising progress in genetic diagnosis in the field of neurological disease research. High-throughput molecular biology techniques, such as microarrays and next-generation sequencing, are the major contributors to this progress and to new discoveries. Charcot-Marie-Tooth disease (CMT), a known hereditary motor and sensory neuropathy, is clinically and genetically heterogeneous. Genetic studies have revealed at least 35 disease causing-genes responsible for Charcot-Marie-Tooth disease. Genetic studies have revealed that abnormalities in the following factors are the cause of inherited neuropathies: myelin components, transcription factors controlling myelination, myelin maintenance system, differentiation factors related to the peripheral nerve, neurofilaments, protein transfer system, mitochondrial proteins, DNA repair, RNA/protein synthesis, ion channels, and aminoacyl-tRNA synthetase. On the other hand concomitant with the increase in the number of genes that must be screened for mutations, the labor and reagent costs for molecular genetic testing have increased significantly. Therefore, new methodology for detecting gene mutations is required. Based on the recent progress in DNA analysis methods, resequencing microarray appears to be an economical and highly sensitive method for detecting mutations. We have been screening CMT patients for mutations using originally designed microarray DNA chips since 2007, thencehaving identified disease causing mutations in MPZ, GJB1, PMP22, EGR2, MFN2, NEFL, PRX, AARS, GARS, DNM2, and SETX genes in CMT patients. PMID:22790800
Takashima, Hiroshi
Meiotic outcomes of three-way translocations ascertained in cleavage-stage embryos: refinement of reproductive risks and implications for PGD.
Our study provides an analysis of the outcome of meiotic segregation of three-way translocations in cleavage-stage embryos and the accuracy and limitations of preimplantation genetic diagnosis (PGD) using the fluorescence in situ hybridization technique. We propose a general model for estimating reproductive risks for carriers of this class of complex chromosome rearrangement. The data presented describe six cycles for four couples where one partner has a three-way translocation. For male heterozygotes, 27.6% of embryos were consistent with 3:3 alternate segregation resulting in a normal or balanced translocation chromosome complement; 41.4% were consistent with 3:3 adjacent segregation of the translocations, comprising 6.9% reflecting adjacent-1 and 34.5% adjacent-2 segregation; 24.1% were consistent with 4:2 nondisjunction; none showed 5:1 or 6:0 segregation; the probable mode could not be ascertained for 6.9% of embryos due to complex mosaicism or nucleus fragmentation. The test accuracy for male heterozygotes was estimated to be 93.1% with 100% sensitivity and 75% specificity. With 72.4% prevalence, the predictive value was estimated to be 91.3% for an abnormal test result and 100% for a normal test result. Two of four couples had a healthy baby following PGD. The proportion of normal/balanced embryo could be significantly less for female heterozygotes, and our model indicates that this could be detrimental to the effectiveness of PGD. A 20% risk of live-born offspring with an unbalanced translocation is generally accepted, largely based on the obstetric history of female heterozygotes; we suggest that a 3% risk may be more appropriate for male carriers. PMID:24129433
Scriven, Paul N; Bint, Susan M; Davies, Angela F; Ogilvie, Caroline Mackie
Genetic imprecision: Diagnosis of possible defects often cannot predict prognosis
The author discusses the difficulties in using current genetic information for the detection of hereditary diseases. Although there have been many advances in cytogenetic and molecular testing, the diagnosis of defects does not necessarily predict prognosis. Detection of mutant alleles, mosaicism, familial chromosomal rearrangements and de novo chromosomal rearrangements lends uncertainties to genetic counselling. The problems have been compounded by a lack of follow-up to determine if a defect actually exists in a fetus aborted as a result of counselling; nor has there been long-term follow-up of fetuses carried to term that appear healthy at birth. Disappointments after the discovery of the cystic fibrosis gene were due to discovery of many mutations of the gene, making screening for the disease difficult. Some genetic counselors question the benefits of screening for this disease since with advances in treatment, life span has been lengthened and quality of life has been improved.
Lewis, R.
Multiple displacement amplification improves PGD for fragile X syndrome
We report an improvement in the PGD test for fragile X syndrome (FXS). Recently, multiple displacement amplification (MDA) has been reported to yield large amounts of DNA from single cells. Taking into account this technique, we developed a new PGD test for FXS, enabling combined analysis of linked polymorphic markers with the study of the non-expanded CGG repeat. Single cell
P. Burlet; N. Frydman; N. Gigarel; V. Kerbrat; G. Tachdjian; E. Feyereisen; J.-P. Bonnefont; R. Frydman; A. Munnich; J. Steffann
High volume molecular genetic identification of single nucleotide polymorphisms using Genetic Bit Analysis Application to human genetic diagnosis
The most common type of genetic disease-associated mutation is the single nucleotide polymorphism (SNP). Because most genetic diseases can be caused by multiple SNPs in the same gene, effective routine diagnosis of complex genetic diseases is dependent on a simple and reliable method of interrogating SNP sites. Molecular Tool`s solid phase assay capable of direct genotyping (single base sequencing) of SNP sites, Genetic Bit Analysis (GBA), involves hybridization-capture of a single-stranded PCR product to a sequence-specific, microtiter plate-bound oligonucleotide primer. The captured PCR product then acts as template for single-base extension of the capture primer across the polymorphic site, enabling direct determination of the base composition of the polymorphism through a simple colormetric assay. Genotyping in a high volume, semi-automated, processing system with a current capacity of 100 SNP interrogations per technician per day enables the screening of candidate mutations rapidly and cost-effectively, critically important to comprehensive genetic diagnosis. Using this gel-free technology, we have developed prototype diagnostic tests for CFTR and ApoE polymorphisms which enable direct sequencing of the polymorphic base at each site of interest. Routine clinical diagnosis of genetically complex diseases such as cystic fibrosis is dependent on this combination of robust biochemistry and simple format. Additionally, the ability to transfer the format and biochemistry to any disease gene of interest enables the broad application of this technology to clinical diagnostics, especially for genetically complex diseases.
Boyce-Jacino, M.T.; Reynolds, J.; Nikiforov, T. [Molecular Tool, Inc., Baltimore, MD (United States)] [and others
Rapid molecular genetic diagnosis of hypertrophic cardiomyopathy by semiconductor sequencing
Background Rapidly determining the complex genetic basis of Hypertrophic cardiomyopathy (HCM) is vital to better understanding and optimally managing this common polygenetic cardiovascular disease. Methods A rapid custom Ion-amplicon-resequencing assay, covering 30 commonly affected genes of HCM, was developed and validated in 120 unrelated patients with HCM to facilitate genetic diagnosis of this disease. With this HCM-specific panel and only 20�ng of input genomic DNA, physicians can, for the first time, go from blood samples to variants within a single day. Results On average, this approach gained 595628 mapped reads per sample, 95.51% reads on target (64.06�kb), 490-fold base coverage depth and 93.24% uniformity of base coverage in CDS regions of the 30 HCM genes. After validation, we detected underlying pathogenic variants in 87% (104 of 120) samples. Tested seven randomly selected HCM genes in eight samples by Sanger sequencing, the sensitivity and false-positive-rate of this HCM panel was 100% and 5%, respectively. Conclusions This Ion amplicon HCM resequencing assay provides a currently most rapid, comprehensive, cost-effective and reliable measure for genetic diagnosis of HCM in routinely obtained samples.
Infertile couples with Robertsonian translocations: preimplantation genetic analysis of embryos reveals chaotic cleavage divisions
Preimplantation genetic diagnosis (PGD) may provide a feasible option for some Robertsonian translocation carriers who experience\\u000a severe difficulty in achieving a normal pregnancy. We report on five PGD cycles for two such couples, 45,XY,der(13;14)(q10:q10)\\u000a and 45,XX,der(13;21)(q10;q10), carried out by biopsy of two cells from day 3 post-insemination embryos generated by in vitro\\u000a fertilisation. Locus-specific YAC probes for chromosomes 13, 14
Clare M. Conn; Joyce C. Harper; Robert M. L. Winston; Joy D. A. Delhanty
Molecular strategies for pre-implantation genetic diagnosis of single gene and chromosomal disorders.
Pre-implantation genetic diagnosis is used to analyse pre-implantation stage embryos or oocytes for genetic defects, generally for severe Mendelian disorders and chromosome abnormalities. New but controversial indications for pre-implantation genetic diagnosis include identifying human leukocyte antigen compatible embryos suitable as donor, sex selection and adult-onset disorders, particularly cancer. Pre-implantation genetic screening is a variant of pre-implantation genetic diagnosis to improve outcomes of in-vitro fertilisation. Array comparative genomic hybridisation is replacing fluorescence in-situ hybridisation for aneuploidy screening. Besides technical advancement of array platform, the success of pre-implantation genetic screening is strongly related to the embryonic biological nature of chromosomal mosaicism. Having been applied for more than 20 years, pre-implantation genetic diagnosis is recognised as an important alternative to prenatal diagnosis. Diagnosis from a single cell, however, remains a technically challenging procedure, and the risk of misdiagnosis cannot be eliminated. PMID:22858134
Jiang, Boran; Tan, Arnold S C; Chong, Samuel S
Preimplantation diagnosis to create 'saviour siblings': a critical discussion of the current and future legal frameworks in South Africa.
Pre-implantation genetic diagnosis (PGD) is a technology used in conjunction with in vitro fertilisation to screen embryos for genetic conditions prior to transfer. It was initially developed to screen mutations for severe, irreversible, genetic conditions. Currently, PGD makes it possible to select against more than 100 different genetic conditions. It has been proposed as a method for creating a tissue-matched child who can in turn serve as a compatible stem cell donor to save a sick sibling in need of a stem cell transplant. The advantage of this method is that it provides genetic information before implantation of an embryo into the womb, making it possible to ensure that only tissue-matched embryos are transferred to the uterus. A couple can therefore avoid the difficult choice of either terminating the pregnancy at a later point if the fetus is not a match, or extending their family again in the hope that their next child will be tissue compatible. Many people have expressed disapproval of the use of PGD for this purpose, and it is associated with many conflicting interests including religion, ethics as well as legal regulation. In order to manage these issues some jurisdictions have created legal frameworks to regulate the use of this technology. Many of these are modelled on the UK's Human Fertilisation and Embryology Authority and its guardian legislation. This paper critiques the current and future South African legal framework to establish whether it is able to adequately regulate the use of PGD as well as guard against misuse of the technology. It concludes that changes are required to the future framework in order to ensure that it regulates the circumstances in which PGD may occur and that the Minister of Health should act expediently in finalising draft regulations which will regulate PGD in the future. PMID:22273130
Strode, Ann; Soni, Sheetal
My Funky Genetics: BRCA1\\/2 Mutation Carriers' Understanding of Genetic Inheritance and Reproductive Merger in the Context of New Reprogenetic Technologies
Deleterious mutations in the BRCA1\\/BRCA2 genes elevate lifetime risk of breast and ovarian cancer. Each child of a mutation-positive parent has a 50% chance of inheriting it. Preimplantation genetic diagnosis (PGD) permits prospective parents to avoid the birth of a BRCA-mutation-positive child, introducing predictability into a process historically defined by chance. This investigation explored how BRCA1\\/2 mutation carriers understand genetic
Allison Werner-Lin; Lisa R. Rubin; Maya Doyle; Rikki Stern; Katie Savin; Karen Hurley; Michal Sagi
Genetic markers for diagnosis and pathogenesis of Alzheimer's disease.
Alzheimer's disease (AD) is the most common form of dementia in the elderly and represents an important and increasing clinical challenge in terms of diagnosis and treatment. Mutations in the genes encoding amyloid precursor protein (APP), presenilin 1 (PSEN1) and presenilin 2 (PSEN2) are responsible for early-onset autosomal dominant AD. The ?4 allele of the apolipoprotein E (APOE) gene has been recognized as a major genetic risk factor for the more common, complex, late-onset AD. Fibrillar deposits by phosphorylated tau are also a key pathological feature of AD. The retromer complex also has been reported to late-onset AD. More recently, genome-wide association studies (GWASs) identified putative novel candidate genes associated with late-onset AD. Lastly, several studies showed that circulating microRNAs (miRNAs) in the cerebrospinal fluid (CSF) and blood serum of AD patients can be used as biomarkers in AD diagnosis. This review addresses the advances and challenges in determining genetic and diagnostic markers for complex AD pathogenesis. PMID:24838203
Kim, Dong Hee; Yeo, Seung Hyeon; Park, Jeong-Min; Choi, Ji Ye; Lee, Tae-Hee; Park, Soon Yong; Ock, Mee Sun; Eo, Jungwoo; Kim, Heui-Soo; Cha, Hee-Jae
Genetic counseling and "molecular" prenatal diagnosis of holoprosencephaly (HPE).
Holoprosencephaly (HPE) is a structural anomaly of the developing brain in which the forebrain fails to divide into two separate hemispheres and ventricles. The poor prognosis in the most severe forms justifies the importance of genetic counseling in affected families. The genetic counseling requires a thorough clinical approach given the extreme variability of phenotype and etiology. The karyotype is an essential diagnostic tool. Since mutations in the four major genes (SHH, ZIC2, SIX3, and TGIF) have been identified in HPE patients, molecular study is performed routinely in nonsyndromic HPE. New molecular tools, such as array-CGH analysis, are now part of the diagnostic process. Prenatal diagnosis is based primarily on fetal imaging, but "molecular" prenatal diagnosis can be performed if a mutation has been previously identified in a proband. Interpretations of molecular diagnosis must be given with caution, given the lack of strict genotype-phenotype correlation, and should be offered in addition to fetal imaging, using ultrasound followed by fetal MRI. We report on our experience of 15 molecular prenatal diagnoses from chorionic villi or amniotic fluid sampling. In eight instances, we were able to reassure the parents after taking into account the absence of the mutation in the fetus, previously identified before in a parent and/or a proband. Fetal RMI was normal later in pregnancy, and no child had medical problems after birth. The mutation was found in the seven other cases: four children were born, either without brain malformation and asymptomatic, or had a less severe form than the index case. PMID:20104616
Mercier, Sandra; Dubourg, Christ�le; Belleguic, Marion; Pasquier, Laurent; Loget, Philippe; Lucas, Josette; Bendavid, Claude; Odent, Sylvie
[Contribution of genetics to pathogenicity and diagnosis of Marfan syndrome].
The anatomical substrate of Marfan's syndrome is a degeneration of elastic fibres and disorganization of the collagen. It is now known that these lesions are due to mutation of genes localised on chromosome 15. The first of them (FBN1) codes for the main constitutive protein of the elastic tissue: fibrillin 1, present mainly in structures which must resist load and stress (aortic adventitia, the suspending ligament of the lens, skin); the second (FBN2) codes for fibrillin 2: responsible for the orientation of the elastin and mainly present in cartilage, the aortic media, the bronchi, and all tissues rich in elastin. Mutations of FBN1 are very common and are associated not only with Marfan's syndrome but also fibrillinopathies: incomplete forms, neonatal forms, ectopic lens, isolated aneurysms of the thoracic aorta. The widespread distribution of fibrillin explains the pleiotropic nature of Marfan's syndrome and its clinical presentation. The variability of interfamilial expression is due to genetic heterogeneity (at least two genes) and alletic differences (different mutations of FBN1 from one family to another), also explaining mild forms due to quantitative reduction in normal fibrillin and severe forms by "negative dominance" where the fibrillin is structurally abnormal because of alteration of the polymerisation mechanism. The biologic diagnosis of fibrillopathy can be made by a protein test analysing fibrillin on a culture of the patient's fibroblast obtained by skin biopsy. At present, molecular diagnosis of the mutation within the FBN1 gene is not feasible as a routine procedure. PMID:9587455
Boileau, C; Collod, G; Bonnet, D
Attitudes toward genetic testing in childhood and reproductive decision-making for familial adenomatous polyposis.
Childhood DNA testing, prenatal diagnosis (PND) and preimplantation genetic diagnosis (PGD) are available for familial adenomatous polyposis (FAP). However, the use of PND and PGD is controversial. The purpose of this study was to investigate attitudes toward, and experiences with, childhood DNA testing, PND and PGD among members of families at high risk for FAP. In this nationwide, cross-sectional study, questionnaires were sent to individuals from families at high risk for FAP assessing attitudes toward and experiences with childhood testing, PND and PGD, as well as several sociodemographic, clinical and psychosocial variables. Of the individuals from FAP families invited to participate in the study, 525 members participated (response rate=64%). Most parents who had children who were minors (n=93) (82%) were satisfied with the DNA testing procedure. One-third of all individuals wanted DNA testing for their children before age 12. Forty percent of FAP patients indicated that the disease influenced their desire to have children. Only 15% considered termination of pregnancy for FAP acceptable. Approximately 30% of individuals with a FAP diagnosis and their partners considered PND and PGD as acceptable for themselves. A positive attitude was associated with higher levels of guilt and a positive attitude toward termination of pregnancy. Importantly, of those with FAP at childbearing age, 84% had had no previous information at all about either PND or PGD. Future efforts should be aimed at educating FAP family members about reproductive options, allowing them to make an informed choice about family planning. Routine discussion of all reproductive options with a medical specialist should be encouraged. PMID:19809485
Douma, Kirsten F L; Aaronson, Neil K; Vasen, Hans F A; Verhoef, Senno; Gundy, Chad M; Bleiker, Eveline M A
Improving family communication after a new genetic diagnosis: a randomised controlled trial of a genetic counselling intervention
Background Genetic information given to an individual newly diagnosed with a genetic condition is likely to have important health implications for other family members. The task of communicating with these relatives commonly falls to the newly diagnosed person. Talking to relatives about genetic information can be challenging and is influenced by many factors including family dynamics. Research shows that many relatives remain unaware of relevant genetic information and the possible impact on their own health. This study aims to evaluate whether a specific genetic counselling intervention for people newly diagnosed with a genetic condition, implemented over the telephone on a number of occasions, could increase the number of at-risk relatives who make contact with genetics services after a new genetic diagnosis within a family. Methods This is a prospective, multi-centre randomised controlled trial being conducted at genetics clinics at five public hospitals in Victoria, Australia. A complex genetic counselling intervention has been developed specifically for this trial. Probands (the first person in a family to present with a diagnosis of a genetic condition) are being recruited and randomised into one of two arms � the telephone genetic counselling intervention arm and the control arm receiving usual care. The number of at-risk relatives for each proband will be estimated from a family pedigree collected at the time of diagnosis. The primary outcome will be measured by comparing the proportion of at-risk relatives in each arm of the trial who make subsequent contact with genetics services. Discussion This study, the first randomised controlled trial of a complex genetic counselling intervention to enhance family communication, will provide evidence about how best to assist probands to communicate important new genetic information to their at-risk relatives. This will inform genetic counselling practice in the context of future genomic testing. Trial registration Australia and New Zealand Clinical Trials Register (ANZCTR): ANZCTRN12608000642381.
Workshop on molecular methods for genetic diagnosis. Final technical report.
The Sarah Lawrence College Human Genetics Program received Department of Energy funding to offer a continuing medical education workshop for genetic counselors in the New York metropolitan area. According to statistics from the National Society of Genetic...
E. M. Rinchik
Diagnosis of Wilson Disease in Young Children: Molecular Genetic Testing and a Paradigm Shift from the Laboratory Diagnosis
Wilson disease (WD) is an autosomal recessive disorder of copper metabolism that results in accumulation of copper primarily in the liver, brain and cornea. Mutations in the WD gene, ATP7B, cause failure of copper excretion from hepatocyte into bile and a defective synthesis of ceruloplasmin. More than 500 mutations are now recognized, scattered throughout the ATP7B gene. Since WD has protean clinical presentations, awareness of WD in clinical practice is important for the early diagnosis and prevention of accumulated copper toxicity. Molecular genetic testing is playing an increasingly important role in the diagnosis of WD in uncertain cases and family screening. Siblings should be screened for WD once an index case has been diagnosed. Discrimination of heterozygotes from asymptomatic patients is essential to avoid inappropriate lifelong therapy for heterozygotes. Genetic testing, either by haplotype analysis or by mutation analysis, is the only definite solution for differentiating heterozygote carriers from affected asymptomatic patients. Routine genetic testing, because of the multitude of documented mutations, has been thought to be impractical until recently. However, genetic testing is now being more actively applied to the diagnosis of WD, particularly in young children in whom conventional biochemical diagnosis has much limitation and only genetic testing is able to confirm WD. Because advancement of modern biochemical technology now allows more rapid, easier, and less expensive mutation detection, direct DNA sequencing could be actively considered as the primary mode of diagnostic investigation rather than a supplementary test to the conventional biochemical tests. This review will focus on the recent advancement of molecular genetics and genetic diagnosis of WD in very young children on the basis of research data of the Seoul National University Children's Hospital and recent literature.
PGD2-CRTH2 Pathway Promotes Tubulointerstitial Fibrosis
Urinary excretion of lipocalin-type PGD2 synthase (L-PGDS), which converts PG H2 to PGD2, increases in early diabetic nephropathy. In addition, L-PGDS expression in the tubular epithelium increases in adriamycin-induced nephropathy, suggesting that locally produced L-PGDS may promote the development of CKD. In this study, we found that L-PGDS�derived PGD2 contributes to the progression of renal fibrosis via CRTH2-mediated activation of Th2 lymphocytes. In a mouse model, the tubular epithelium synthesized L-PGDS de novo after unilateral ureteral obstruction (UUO). L-PGDS-knockout mice and CRTH2-knockout mice both exhibited less renal fibrosis, reduced infiltration of Th2 lymphocytes into the cortex, and decreased production of the Th2 cytokines IL-4 and IL-13. Furthermore, oral administration of a CRTH2 antagonist, beginning 3 days after UUO, suppressed the progression of renal fibrosis. Ablation of IL-4 and IL-13 also ameliorated renal fibrosis in the UUO kidney. Taken together, these data suggest that blocking the activation of CRTH2 by PGD2 might be a strategy to slow the progression of renal fibrosis in CKD.
Yan, Xiaoxiang; Nagata, Nanae; Aritake, Kosuke; Katsumata, Yoshinori; Matsuhashi, Tomohiro; Nakamura, Masataka; Hirai, Hiroyuki; Urade, Yoshihiro; Asano, Koichiro; Kubo, Masato; Utsunomiya, Yasunori; Hosoya, Tatsuo; Fukuda, Keiichi; Sano, Motoaki
Critical Issues for Dentistry: PGD Program Directors Respond.
ERIC Educational Resources Information Center
Surveyed directors of programs in postgraduate education in general dentistry (PGD) about critical issues facing their programs. Identified 12 themes: lack of postdoctoral applicants; student quality; professionalism and attitudes; number of postdoctoral positions; lack of funding; quality of facilities; special patient care; program curriculum;�
Atchison, Kathryn A.; Cheffetz, Susan E.
6-phosphogluconate dehydrogenase in the housefly, Musca domestica L.: Evidence for inheritable 6PGD polymorphism
Two electrophoretic variants of the 6-phosphogluconate dehydrogenase (6PGD) enzyme have been found in the WHO\\/IN\\/Musca domestica\\/1 housefly laboratory strain. The patterns shown by Cellogel zone electrophoresis can be fully explained by the hypothesis of two codominant autosomal alleles. On this hypothesis, a specific Pgd locus has been postulated and the symbols PgdA and PgdB have been assigned to the two
G. Gasperi; A. Malacrida; R. Milani
The controversy about to which extend PGD may be applies is particularly interesting because it stresses on a paradoxical point concerning PGD. Although this technique is strictly regulated in most European countries where it is regularly practised, the legal status of PGD may appear to some as unethical because it may be viewed as a facilitator for those who would like to select children for reason other than medical. The need to test human embryos before birth and the consequences that may occur to those detected with some abnormalities also revives the issue of the respect due to the human embryo. PMID:19244944
Byk, Christian
Male and female meiotic behaviour of an intrachromosomal insertion determined by preimplantation genetic diagnosis
BACKGROUND: Two related family members, a female and a male balanced carrier of an intrachromosomal insertion on chromosome 7 were referred to our centre for preimplantation genetic diagnosis. This presented a rare opportunity to investigate the behaviour of the insertion chromosome during meiosis in two related carriers. The aim of this study was to carry out a detailed genetic analysis
Leoni Xanthopoulou; Anna Mantzouratou; Anastasia Mania; Suzanne Cawood; Alpesh Doshi; Domenico M Ranieri; Joy DA Delhanty
The use of molecular genetic analysis in the diagnosis of renal cell carcinoma
The most common genetic aberration seen in nonpapillary renal cell carcinoma is believed to be the loss or inactivation of allelic material on the short arm of chromosome 3 (3p). Two patients underwent nephrectomy at our institution, each initially receiving a histologic diagnosis of renal cell carcinoma. Molecular analysis of these tissues revealed no genetic deletion on 3p, prompting further
J. P. Long; P. Anglard; J. R. Gnarra; M. M. Walther; M. J. Merino; S. Liu; M. I. Lerman; B. Zbar; W. M. Linehan
The PGD2 pathway, independently of FGF9, amplifies SOX9 activity in Sertoli cells during male sexual differentiation
Activation by the Y-encoded testis determining factor SRY and maintenance of expression of the Sox9 gene encoding the central transcription factor of Sertoli cell differentiation are key events in the mammalian sexual differentiation program. In the mouse XY gonad, SOX9 upregulates Fgf9, which initiates a Sox9/Fgf9 feedforward loop, and Sox9 expression is stimulated by the prostaglandin D2 (PGD2) producing lipocalin prostaglandin D synthase (L-PGDS, or PTDGS) enzyme, which accelerates commitment to the male pathway. In an attempt to decipher the genetic relationships between Sox9 and the L-Pgds/PGD2 pathway during mouse testicular organogenesis, we found that ablation of Sox9 at the onset or during the time window of expression in embryonic Sertoli cells abolished L-Pgds transcription. By contrast, L-Pgds-/- XY embryonic gonads displayed a reduced level of Sox9 transcript and aberrant SOX9 protein subcellular localization. In this study, we demonstrated genetically that the L-Pgds/PGD2 pathway acts as a second amplification loop of Sox9 expression. Moreover, examination of Fgf9-/- and L-Pgds-/- XY embryonic gonads demonstrated that the two Sox9 gene activity amplifying pathways work independently. These data suggest that, once activated and maintained by SOX9, production of testicular L-PGDS leads to the accumulation of PGD2, which in turn activates Sox9 transcription and nuclear translocation of SOX9. This mechanism participates together with FGF9 as an amplification system of Sox9 gene expression and activity during mammalian testicular organogenesis.
Moniot, Brigitte; Declosmenil, Faustine; Barrionuevo, Francisco; Scherer, Gerd; Aritake, Kosuke; Malki, Safia; Marzi, Laetitia; Cohen-Solal, Anne; Georg, Ina; Klattig, Jurgen; Englert, Christoph; Kim, Yuna; Capel, Blanche; Eguchi, Naomi; Urade, Yoshihiro; Boizet-Bonhoure, Brigitte; Poulat, Francis
Centrifuge modeling of PGD response of buried pipe
NASA Astrophysics Data System (ADS)
A new centrifuge based method for determining the response of continuous buried pipe to PGD is presented. The physical characteristics of the RPI's 100 g-ton geotechnical centrifuge and the current lifeline experiment split-box are described: The split-box contains the model pipeline and surrounding soil and is manufactured such that half can be offset, in flight, simulating PGD. In addition, governing similitude relations which allow one to determine the physical characteristics, (diameter, wall thickness and material modulus of elasticity) of the model pipeline are presented. Finally, recorded strains induced in two buried pipes with prototype diameters of 0.63 m and 0.95 m (24 and 36 inch) subject to 0.6 and 2.0 meters (2 and 6 feet) of full scale fault offsets and presented and compared to corresponding FE results.
O'Rourke, Michael; Gadicherla, Vikram; Abdoun, Tarek
Molecular approaches in the prenatal diagnosis and therapy of genetic disorders.
During the last decade a new class of DNA markers, the restriction fragment length polymorphisms (RFLPs), has been developed by molecular genetic techniques. Genetic linkage studies using RFLPs have resulted in a large number of chromosome assignments of genes, making possible prenatal diagnosis and presymptomatic testing in many genetic disorders. Even so, of the estimated 100,000 genes that comprise the human genome fewer than 2,000, or 2%, have been mapped. Studies of the molecular basis of some of these mutant genes have brought to light a remarkable multiplicity and diversity of mutations that produce relatively few clinical phenotypes. Many genetic disorders including the thalassemias, familial hypercholesterolemia, Tay-Sachs disease, cystic fibrosis, and congenital adrenal hyperplasia, have been shown to be genetically heterogeneous. It is necessary, therefore, to know the precise mutation in order to make accurate diagnosis and restore proper enzyme or gene function. PMID:2907713
Myrianthopoulos, N C
Targeted massively parallel sequencing provides comprehensive genetic diagnosis for patients with disorders of sex development
Disorders of sex development (DSD) are rare disorders in which there is discordance between chromosomal, gonadal, and phenotypic sex. Only a minority of patients clinically diagnosed with DSD obtains a molecular diagnosis, leaving a large gap in our understanding of the prevalence, management, and outcomes in affected patients. We created a novel DSD-genetic diagnostic tool, in which sex development genes are captured using RNA probes and undergo massively parallel sequencing. In the pilot group of 14 patients, we determined sex chromosome dosage, copy number variation, and gene mutations. In the patients with a known genetic diagnosis (obtained either on a clinical or research basis), this test identified the molecular cause in 100% (7/7) of patients. In patients in whom no molecular diagnosis had been made, this tool identified a genetic diagnosis in two of seven patients. Targeted sequencing of genes representing a specific spectrum of disorders can result in a higher rate of genetic diagnoses than current diagnostic approaches. Our DSD diagnostic tool provides for first time, in a single blood test, a comprehensive genetic diagnosis in patients presenting with a wide range of urogenital anomalies.
Arboleda, VA; Lee, H; Sanchez, FJ; Delot, EC; Sandberg, DE; Grody, WW; Nelson, SF; Vilain, E
Guidelines for the genetic diagnosis of hereditary recurrent fevers
Hereditary recurrent fevers (HRFs) are a group of monogenic autoinflammatory diseases characterised by recurrent bouts of fever and serosal inflammation that are caused by pathogenic variants in genes important for the regulation of innate immunity. Discovery of the molecular defects responsible for these diseases has initiated genetic diagnostics in many countries around the world, including the Middle East, Europe, USA, Japan and Australia. However, diverse testing methods and reporting practices are employed and there is a clear need for consensus guidelines for HRF genetic testing. Draft guidelines were prepared based on current practice deduced from previous HRF external quality assurance schemes and data from the literature. The draft document was disseminated through the European Molecular Genetics Quality Network for broader consultation and amendment. A workshop was held in Bruges (Belgium) on 18 and 19 September 2011 to ratify the draft and obtain a final consensus document. An agreed set of best practice guidelines was proposed for genetic diagnostic testing of HRFs, for reporting the genetic results and for defining their clinical significance.
Shinar, Y; Obici, L; Aksentijevich, I; Bennetts, B; Austrup, F; Ceccherini, I; Costa, J M; De Leener, A; Gattorno, M; Kania, U; Kone-Paut, I; Lezer, S; Livneh, A; Moix, I; Nishikomori, R; Ozen, S; Phylactou, L; Risom, L; Rowczenio, D; Sarkisian, T; van Gijn, M E; Witsch-Baumgartner, M; Morris, M; Hoffman, H M; Touitou, I
Guidelines for the genetic diagnosis of hereditary recurrent fevers.
Hereditary recurrent fevers (HRFs) are a group of monogenic autoinflammatory diseases characterised by recurrent bouts of fever and serosal inflammation that are caused by pathogenic variants in genes important for the regulation of innate immunity. Discovery of the molecular defects responsible for these diseases has initiated genetic diagnostics in many countries around the world, including the Middle East, Europe, USA, Japan and Australia. However, diverse testing methods and reporting practices are employed and there is a clear need for consensus guidelines for HRF genetic testing. Draft guidelines were prepared based on current practice deduced from previous HRF external quality assurance schemes and data from the literature. The draft document was disseminated through the European Molecular Genetics Quality Network for broader consultation and amendment. A workshop was held in Bruges (Belgium) on 18 and 19 September 2011 to ratify the draft and obtain a final consensus document. An agreed set of best practice guidelines was proposed for genetic diagnostic testing of HRFs, for reporting the genetic results and for defining their clinical significance. PMID:22661645
Ethical and legal aspects of noninvasive prenatal genetic diagnosis.
The new technology that will allow genetic testing of a fetus within the first trimester of pregnancy by isolating cell-free fetal DNA (cffDNA) in the mother's blood raises a range of ethical and legal issues. Considered noninvasive, this test is safe and reliable, and may avoid alternative genetic testing by amniocentesis or chorionic villus sampling, which risks causing spontaneous abortion. Ethical and legal issues of cffDNA testing will become more acute if testing expands to fetal whole-genome sequencing. Critical issues include the state of the science or diagnostic art; the appropriateness of offering the test; the implications of denying the test when it is available and appropriate; disclosure and counseling following test results; and management of patients' choices on acquiring test results. A challenge will be providing patients with appropriate counseling based on up-to-date genetic knowledge, and accommodating informed patients' legal choices. PMID:24299974
Dickens, Bernard M
Recent advances in the diagnosis, genetics and treatment of restless legs syndrome
\\u000a Abstract\\u000a ��Knowledge of restless legs syndrome (RLS) has greatly increased in recent years due to the many advances that have been made\\u000a in diagnosis, management and genetics. Tools have been developed that facilitate the diagnosis and treatment of RLS, in particular\\u000a the essential diagnostic criteria for RLS have been refined, severity scales (IRLS, RLS-6, JHSS) have been developed, as have
Claudia Trenkwalder; Birgit H�gl; Juliane Winkelmann
From brute luck to option luck? On genetics, justice, and moral responsibility in reproduction.
The structure of our ethical experience depends, crucially, on a fundamental distinction between what we are responsible for doing or deciding and what is given to us. As such, the boundary between chance and choice is the spine of our conventional morality, and any serious shift in that boundary is thoroughly dislocating. Against this background, I analyze the way in which techniques of prenatal genetic diagnosis (PGD) pose such a fundamental challenge to our conventional ideas of justice and moral responsibility. After a short description of the situation, I first examine the influential luck egalitarian theory of justice, which is based on the distinction between choice and luck or, more specifically, between option luck and brute luck, and the way in which it would approach PGD (section II), followed by an analysis of the conceptual incoherencies (in section III) and moral problems (in section IV) that come with such an approach. Put shortly, the case of PGD shows that the luck egalitarian approach fails to express equal respect for the individual choices of people. The paradox of the matter is that by overemphasizing the fact of choice as such, without regard for the social framework in which they are being made, or for the fundamental and existential nature of particular choices-like choosing to have children and not to undergo PGD or not to abort a handicapped fetus-such choices actually become impossible. PMID:20181644
Denier, Yvonne
Assessing pre-implantation embryo development in mice provides a rationale for understanding potential adverse effects of ART and PGD procedures.
Although the molecular events controlling human pre-implantation development remain unclear, mechanisms have been identified by analyzing these stages in mice. Through this approach, considerable insight has been gained into the events that operate to determine the first two cell fate decisions, occurring from zygote formation to the blastocyst prior to implantation. These mechanisms are related to cell polarization, cell division, cell-cell contact, and cell spatial position. Two developmental stages are essential for these processes to proceed adequately. Firstly, the second polar body must anchor to the external membrane during the first mitotic divisions of the embryo as its position is strongly biased to determine the plane of polarity. This in turn has important influence on the fate of the early blastomeres. Secondly, in the transition from the 8- to 16-cell stage, the cells that will form the inner cell mass are determined. Moreover, analyses performed on human oocytes and embryos have identified similar processes to those reported in mice and thus are evolutionarily conserved. Therefore, the understanding of mice pre-implantation embryo development provides a rationale to interpret current results of potential long-term adverse outcomes of Assisted Reproductive Technologies and Pre-implantation Genetic Diagnosis (PGD). PMID:22903927
Mart�nez-Fr�as, Mar�a Luisa
Functional Constraints of 6Phosphogluconate Dehydrogenase (6-PGD) Based on Sequence and Structural Information
The pentose phosphate cycle is considered as a major source of NADPH and pentose needed for nucleic acid biosynthesis. 6-Phosphogluconate dehydrogenase (6PGD), an enzyme participating in this cycle, catalyzes the oxidative decarboxylation of 6PGD to ribulose 5-phosphate with the subsequent release of CO2 and the reduction of NADP. We have determined the amino acid sequence of 6PGD of Bactrocera oleae
George N. Goulielmos; Elias Eliopoulos; Michael Loukas; Spyros Tsakas
Attitudes to reproductive genetic testing in women who had a positive BRCA test before having children: a qualitative analysis
The scope of conditions for which preimplantation genetic diagnosis (PGD) is licensed has recently been expanded in the United Kingdom to include genetic predisposition to adult-onset cancer. This qualitative interview study explores reproductive decision making, knowledge of and attitudes to reproductive genetic testing (prenatal diagnosis and PGD) with 25 women aged 18�45 years who received a positive BRCA test in the United Kingdom before having children. In this cohort of younger women, BRCA testing was motivated by risk management decisions; for some, BRCA status has affected their later decisions about having children. The perceived severity of hereditary breast/ovarian cancer (HBOC) influences thoughts about passing on the mutation to children and willingness to consider reproductive genetic testing, but most participants do not believe HBOC is a condition for which pregnancy termination is justified. PGD is considered more acceptable and advantageous because it would prevent transmission to future generations, but women have concerns about selecting embryos and the fact that they and affected family members would not have been selected. Women would also be deterred by the need to undergo in vitro fertilisation (IVF) and ovarian stimulation for PGD. Awareness of reproductive testing options was very variable among the cohort. The findings highlight the complexities of reproductive decision making for young women who knowingly carry a BRCA mutation, and the dilemmas inherent to reproductive genetic testing when the condition being tested for also affects a prospective parent. Counselling and psychological support for BRCA-positive women and couples concerning reproductive options are strongly indicated.
Ormondroyd, Elizabeth; Donnelly, Louise; Moynihan, Clare; Savona, Cornelie; Bancroft, Elizabeth; Evans, D Gareth; Eeles, Rosalind; Lavery, Stuart; Watson, Maggie
Small Ruminant Lentiviruses: Genetic Variability, Tropism and Diagnosis
Small ruminant lentiviruses (SRLV) cause a multisystemic chronic disease affecting animal production and welfare. SRLV infections are spread across the world with the exception of Iceland. Success in controlling SRLV spread depends largely on the use of appropriate diagnostic tools, but the existence of a high genetic/antigenic variability among these viruses, the fluctuant levels of antibody against them and the low viral loads found in infected individuals hamper the diagnostic efficacy. SRLV have a marked in vivo tropism towards the monocyte/macrophage lineage and attempts have been made to identify the genome regions involved in tropism, with two main candidates, the LTR and env gene, since LTR contains primer binding sites for viral replication and the env-encoded protein (SU ENV), which mediates the binding of the virus to the host�s cell and has hypervariable regions to escape the humoral immune response. Once inside the host cell, innate immunity may interfere with SRLV replication, but the virus develops counteraction mechanisms to escape, multiply and survive, creating a quasi-species and undergoing compartmentalization events. So far, the mechanisms of organ tropism involved in the development of different disease forms (neurological, arthritic, pulmonary and mammary) are unknown, but different alternatives are proposed. This is an overview of the current state of knowledge on SRLV genetic variability and its implications in tropism as well as in the development of alternative diagnostic assays.
Ramirez, Hugo; Reina, Ramses; Amorena, Beatriz; de Andres, Damian; Martinez, Humberto A.
Fault diagnosis method for machinery in unsteady operating condition by instantaneous power spectrum and genetic programming
This paper proposes a fault diagnosis method for plant machinery in an unsteady operating condition using instantaneous power spectrum (IPS) and genetic programming (GP). IPS is used to extract feature frequencies of each machine state from measured vibration signals for distinguishing faults by relative crossing information. Excellent symptom parameters for detecting faults are automatically generated by the GP. The excellent
Peng Chen; Masatoshi Taniguchi; Toshio Toyota; Zhengja He
Failure diagnosis method for machinery in unsteady operating condition by instantaneous power spectrum and genetic programming
The paper proposes a failure diagnosis method for machinery in unsteady operating condition using instantaneous power spectrum (IPS) and genetic programming (GP). The IPS is used to extract feature frequency of each machine state from measured vibration signal for distinguishing failures by the Relative Crossing Information (RCI). Excellent symptom parameters for detecting failures are automatically generated by GP. The method
Peng Chen; Toshio Toyota; Masatoshi Taniguchi; Fang Feng; T. Hiho
The impact of next-generation sequencing technology on preimplantation genetic diagnosis and screening.
Largely because of efforts required to complete the Human Genome Project, DNA sequencing has undergone a steady transformation with still-ongoing developments of high-throughput sequencing machines for which the cost per reaction is falling drastically. Similarly, the fast-changing landscape of reproductive technologies has been improved by genetic approaches. Preimplantation genetic diagnosis and screening were established more than two decades ago for selecting genetically normal embryos to avoid inherited diseases and to give the highest potential to achieve stable pregnancies. Most recent additions to the IVF practices (blastocyst/trophectoderm biopsy, embryo vitrification) and adoption of new genetics tools such as array comparative genome hybridization have allowed setting up more precise and efficient programs for clinical embryo diagnosis. Nevertheless, there is always room for improvements. Remarkably, a recent explosion in the release of advanced sequencing benchtop platforms, together with a certain maturity of bioinformatics tools, has set the target goal of sequencing individual cells for embryo diagnosis to be a realistically feasible scenario for the near future. Next-generation sequencing technology should provide the opportunity to simultaneously analyze single-gene disorders and perform an extensive comprehensive chromosome screening/diagnosis by concurrently sequencing, counting, and accurately assembling millions of DNA reads. PMID:23499002
Mart�n, Julio; Cervero, Ana; Mir, Pere; Martinez-Conejero, Jose Antonio; Conejero Martinez, Jose Antonio; Pellicer, Antonio; Sim�n, Carlos
Automated Test Assembly for Cognitive Diagnosis Models Using a Genetic Algorithm
Much recent psychometric literature has focused on cognitive diagnosis models (CDMs), a promising class of instruments used to measure the strengths and weaknesses of examinees. This article introduces a genetic algorithm to perform automated test assembly alongside CDMs. The algorithm is flexible in that it can be applied whether the goal is to�
Finkelman, Matthew; Kim, Wonsuk; Roussos, Louis A.
Clinical applications of schizophrenia genetics: genetic diagnosis, risk, and counseling in the molecular era
Schizophrenia is a complex neuropsychiatric disease with documented clinical and genetic heterogeneity, and evidence for neurodevelopmental origins. Driven by new genetic technologies and advances in molecular medicine, there has recently been concrete progress in understanding some of the specific genetic causes of this serious psychiatric illness. In particular, several large rare structural variants have been convincingly associated with schizophrenia, in targeted studies over two decades with respect to 22q11.2 microdeletions, and more recently in large-scale, genome-wide case-control studies. These advances promise to help many families afflicted with this disease. In this review, we critically appraise recent developments in the field of schizophrenia genetics through the lens of immediate clinical applicability. Much work remains in translating the recent surge of genetic research discoveries into the clinic. The epidemiology and basic genetic parameters (such as penetrance and expression) of most genomic disorders associated with schizophrenia are not yet well characterized. To date, 22q11.2 deletion syndrome is the only established genetic subtype of schizophrenia of proven clinical relevance. We use this well-established association as a model to chart the pathway for translating emerging genetic discoveries into clinical practice. We also propose new directions for research involving general genetic risk prediction and counseling in schizophrenia.
Costain, Gregory; Bassett, Anne S
Genetic and biochemical approach to early prenatal diagnosis in a family with mut methylmalonic aciduria.
Genetic and biochemical prenatal diagnosis was performed at 11 weeks of gestation in a family with a proband affected by mut methylmalonic aciduria (MMA) and homozygotes for the MUT gene c.643G>A (p.Gly215Ser) mutation. Both chorionic villus and amniotic fluid samples were used. The presence of high levels of methylmalonic acid and propionylcarnitine determined by gas chromatography/mass spectrometry and LC/MS/MS analysis, respectively, and the identification of the p.Gly215Ser at a homozygous level in foetal DNA allowed a certain, rapid and early diagnosis. To our knowledge, this is the first mut MMA prenatal diagnosis carried out by genetic and biochemical approach. PMID:16451139
Cavicchi, C; Donati, M A; Funghini, S; la Marca, G; Malvagia, S; Ciani, F; Poggi, G M; Pasquini, E; Zammarchi, E; Morrone, A
Narrative Review: Harnessing Molecular Genetics for the Diagnosis and Management of Hypertrophic Cardiomyopathy
Unexplained cardiac hypertrophy, the diagnostic criterion for hypertrophic cardiomyopathy (HCM), occurs in 1 in 500 adults. Insights into the genetic cause and molecular pathophysiology of HCM are reshaping clinical paradigms for diagnosis and treatment of this common myocardial disorder. Human genetic studies have established that dominant mutations in the proteins that make up the contractile apparatus (the sarcomere) cause HCM. With the current availability of clinical gene-based diagnostics, pathogenic mutations in affected patients can be defined, which can suggest a clinical course and allow definitive preclinical identification of family members at risk for HCM. Genetic discoveries have also fostered mechanistic investigations in model organisms that are engineered to carry human HCM mutations. Novel therapeutic targets have emerged from these fundamental studies and are currently under clinical assessment in humans. The combination of contemporary gene-based diagnosis with new strategies to attenuate disease development and progression is changing the natural history of lifelong cardiac symptoms, arrhythmias, and heart failure from HCM.
Libin Wang (University of Miami); Jonathan G. Seidman (Harvard Medical School); Christine E. Seidman (Harvard Medical School)
Blastocystis: Genetic diversity and molecular methods for diagnosis and epidemiology
Blastocystis, an unusual anaerobic, single-celled stramenopile, is a remarkably successful intestinal parasite of a vast array of host species including humans. Fecal Deoxyribonucleic acid (DNA) analysis by nucleic-acid based methods in particular has led to significant advances in Blastocystis diagnostics and research over the past few years enabling accurate identification of carriers and molecular characterization by high discriminatory power. Moreover, Blastocystis comprises a multitude of subtypes (STs) (arguably species) many of which have been identified only recently and molecular epidemiological studies have revealed a significant difference in the distribution of STs across host species and geographical regions. Having a cosmopolitan distribution, the parasite is a common laboratory finding in the stools of individuals with and without intestinal symptoms across the entire globe and while the parasite remains extremely difficult to eradicate and isolate in culture, appropriate molecular tools are now available to resolve important questions such as whether the clinical outcome of colonization is linked to ST and whether Blastocystis is transmitted zoonotically. This review summarizes some of the recent advances in the molecular diagnosis of Blastocystis and gives an introduction to Blastocystis STs, including a recommendation of subtyping methodology based on recent data and method comparisons. A few suggestions for future directions and research areas are given in the light of relevant technological advances and the availability of mitochondrial and nuclear genomes.
Stensvold, Christen Rune
Blastocystis: Genetic diversity and molecular methods for diagnosis and epidemiology.
Blastocystis, an unusual anaerobic, single-celled stramenopile, is a remarkably successful intestinal parasite of a vast array of host species including humans. Fecal Deoxyribonucleic acid (DNA) analysis by nucleic-acid based methods in particular has led to significant advances in Blastocystis diagnostics and research over the past few years enabling accurate identification of carriers and molecular characterization by high discriminatory power. Moreover, Blastocystis comprises a multitude of subtypes (STs) (arguably species) many of which have been identified only recently and molecular epidemiological studies have revealed a significant difference in the distribution of STs across host species and geographical regions. Having a cosmopolitan distribution, the parasite is a common laboratory finding in the stools of individuals with and without intestinal symptoms across the entire globe and while the parasite remains extremely difficult to eradicate and isolate in culture, appropriate molecular tools are now available to resolve important questions such as whether the clinical outcome of colonization is linked to ST and whether Blastocystis is transmitted zoonotically. This review summarizes some of the recent advances in the molecular diagnosis of Blastocystis and gives an introduction to Blastocystis STs, including a recommendation of subtyping methodology based on recent data and method comparisons. A few suggestions for future directions and research areas are given in the light of relevant technological advances and the availability of mitochondrial and nuclear genomes. PMID:23961438
Role of molecular genetics in transforming diagnosis of diabetes mellitus.
Most common diseases also run in families as rare, monogenic forms. Diabetes is no exception. Mutations in approximately 20 different genes are now known to cause monogenic diabetes, a disease group that can be subclassified into maturity-onset diabetes of the young, neonatal diabetes and mitochondrial diabetes. In some families, additional features, such as urogenital malformations, exocrine pancreatic dysfunction and neurological abnormalities, are present and may aid the diagnostic classification. The finding of a mutation in monogenic diabetes may have implications for the prediction of prognosis and choice of treatment. Mutations in the GCK gene cause a mild form of diabetes, which seldom needs insulin and has a low risk for complications. By contrast, HNF1A mutations lead to a diabetes form that in severity, treatment and complication risk resembles Type 1 diabetes, although these patients may experience a good effect of sulfonylurea treatment. The majority of neonatal diabetes cases are caused by mutations in the K(ATP) channel genes ABCC8 and KCNJ11, and sulfonylurea therapy is then usually superior to insulin. Diseases with a considerable genetic component may now be explored by genome-wide approaches using next-generation DNA sequencing technology. We expect that within a few years important breakthroughs will be made in mapping cases of diabetes with a suspected, but still unsolved monogenic basis. PMID:21463240
Molven, Anders; Nj�lstad, P�l R
Hyperinsulinaemic hypoglycaemia:genetic mechanisms, diagnosis and management.
Hyperinsulinaemic hypoglycaemia (HH) is characterized by unregulated insulin secretion from pancreatic ?-cells. Untreated hypoglycaemia in infants can lead to seizures, developmental delay, and subsequent permanent brain injury. Early identification and meticulous managementof these patients is vital to prevent neurological insult. Mutations in eight different genes (ABCC8, KCNJ11, GLUD1, CGK, HADH, SLC16A1, HNF4A and UCP2) have been identified to date in patients with congenital forms of hyperinsulinism (CHI). The most severe forms of CHI are due to mutations in ABCC8 and KCJN11, which encode the two components of pancreatic ?-cell ATP-sensitive potassium channel. Recent advancement in understanding the genetic aetiology, histological characterisation into focal and diffuse variety combined with improved imaging (such as fluorine 18 L-3, 4-dihydroxyphenylalanine positron emission tomography 18F-DOPA-PET scanning) and laparoscopic surgical techniques have greatly improved management. In adults, HH can be due to an insulinoma, pancreatogenous hypoglycaemic syndrome, post gastric-bypass surgery for morbid obesity as well as to mutations in insulin receptor gene. This review provides an overview of the molecular basis of CHI and outlines the clinical presentation, diagnostic criteria, and management of these patients. PMID:23032149
Development of screening assays and discovery of initial inhibitors of pneumococcal peptidoglycan deacetylase PgdA.
The essential cell wall peptidoglycan is the target of several components of the innate immune system and its disruption results in lysis of invading bacteria. The pathogen Streptococcus pneumoniae produces a peptidoglycan N-acetylglucosamine deacetylase, PgdA, to modify the peptidoglycan structure. The activity of PgdA contributes to the bacteria's resistance to lysozyme, which is an important antimicrobial factor of the human innate immune system. In this study we report on the activity of PgdA against natural and artificial substrates. We have also established a virtual high-throughput screening and a new enzyme assay to search for compounds inhibiting PgdA. Two compounds with IC(50) values in the micromolar range have been identified and they could serve as leads for the search of inhibitors of PgdA, an important pneumococcal virulence factor. PMID:21501597
Bui, Nhat Khai; Turk, Samo; Buckenmaier, Stephan; Stevenson-Jones, Flint; Zeuch, Benjamin; Gobec, Stanislav; Vollmer, Waldemar
Gene scene: Earlier, eventually more specific, prenatal genetic diagnosis in realm of possibility
A new genetic technique that can amplify the DNA of a single cell has flung open the window of opportunity for prenatal genetic diagnosis to just 3 days after conception, and even to the unfertilized egg. In vitro fertilization (IVF) specialists at the Institute of Obstetrics and Gynecology at London's Postgraduate medical School, Hammersmith Hospital have determined the sex of human embryos at the eight-cell stage of development from five couples at risk for X chromosome-linked diseases. The female embryos, which do not risk inheriting the disease, were then successfully implanted in the uterus and carried to full term.
Randall, T.
Modeling the genetic and environmental association between peer group deviance and cannabis use in male twins
Background Peer group deviance (PGD) is strongly linked to liability to drug use including cannabis. Our aim was to model the genetic and environmental association, including direction of causation, between PGD and cannabis use (CU). Method Results were based on 1753 adult males from the Mid-Atlantic Twin Registry with complete CU and PGD data measured retrospectively at three time intervals between 15 and 25 years using a life-history calendar. Results At all ages, multivariate modeling showed that familial aggregation in PGD was explained by a combination of additive genetic and shared environmental effects, Moreover the significant PGD-CU association was best explained by a CU to PGD causal model in which large portions of the additive genetic (50% to 78%) and shared environmental variance (25% to 73%) in PGD were explained by CU. Conclusions Until recently PGD was assumed to be an environmental, upstream risk factor for CU. Our data are not consistent with this hypothesis. Rather, they suggest that the liability to affiliate with deviant peers is better explained by a combination of genetic and environmental factors that are indexed by CU which sits as a �risk indicator� in the causal pathway between genetic and environmental risks and the expression of PGD. This is consistent with a process of social selection by which the genetic and environmental risks in CU largely drive the propensity to affiliate with deviant peers.
Gillespie, Nathan A; Neale, Michael C; Jacobson, Kristen; Kendler, Kenneth S
Case report: birth of healthy twins after preimplantation genetic diagnosis of propionic acidemia
Purpose��Development of an ad hoc protocol for the preimplantion genetic diagnosis of propionic acidemia in a couple carrying the mutations c.737G>T (G246V)\\u000a and c.1218del14ins12 (ins\\/del) in the PCCB gene. Propionic acidemia is an autosomal recessive metabolic disorder where the body is unable to process certain parts of\\u000a proteins and lipids. Symptoms manifest few days after birth and sometimes progress to
Trinitat M. Alberola; Rosa Bautista-Ll�cer; Xavier Vendrell; Elena Garc�a-Mengual; Merche Pardo; Maria Vila; Carmen Calatayud
A genetic algorithm based nearest neighbor classification to breast cancer diagnosis
This paper presents an application of a hybrid approach (the genetic algorithms and the k-nearest neighbour) proposed by Ishbuchi\\u000a [10] toWisconsin breast cancer data. For the diagnosis of breast cancer, the determination of the presence ofbenign\\/malignant breast tumors represents a very complex problem (even for an experienced cytologist) [4]. Therefore the automatic classification\\u000a ofbenign andmalignant symptoms is highly desirable as
R. Jain; J. Mazumdar
MEGA-MD: molecular evolutionary genetics analysis software with mutational diagnosis of amino acid variation.
Computational diagnosis of amino acid variants in the human exome is the first step in assessing the disruptive impacts of non-synonymous single nucleotide variants (nsSNVs) on human health and disease. The Molecular Evolutionary Genetics Analysis software with mutational diagnosis (MEGA-MD) is a suite of tools developed to forecast the deleteriousness of nsSNVs using multiple methods and to explore nsSNVs in the context of the variability permitted in the long-term evolution of the affected position. In its graphical interface for use on desktops, it enables interactive computational diagnosis and evolutionary exploration of nsSNVs. As a web service, MEGA-MD is suitable for diagnosing variants on an exome scale. The MEGA-MD suite intends to serve the needs for conducting low- and high-throughput analysis of nsSNVs in diverse applications. PMID:24413669
Stecher, Glen; Liu, Li; Sanderford, Maxwell; Peterson, Daniel; Tamura, Koichiro; Kumar, Sudhir
Feasibility study for a microchip-based approach for noninvasive prenatal diagnosis of genetic diseases.
Fetal DNA in maternal plasma may represent a source of genetic material for prenatal noninvasive diagnosis of genetic diseases. We evaluated a cohort of physiological pregnancies to determine if fetal DNA can be retrieved at any gestational week in sufficient quantity to be analyzed with advanced mutation detection technologies. We performed fetal DNA quantification by real-time polymerase chain reaction (PCR) on the SRY gene in 356 women sampled from 6 to 40 gestational weeks. Fetal DNA was retrieved at any week. All female fetuses were correctly identified. In 5 of 188 (2.6%) male-bearing pregnancies, no amplification was obtained. For noninvasive testing, complete clearance of fetal DNA after delivery is mandatory. Long-term persistence was not detected in women with previous sons or abortions. These findings confirm that maternal plasma may represent the optimal source of fetal genetic material. For noninvasive diagnosis of genetic diseases, we evaluated microchip technology. The detection limit for a minority allele determined by diluting a mutated DNA into a wild-type plasma sample was 5 genome equivalents, indicating that the test might be applied to the identification of paternally inherited fetal alleles in maternal plasma. The addition of peptide nucleic acids (PNAs) to either the PCR reaction or the chip hybridization mixture allowed approximately 50% inhibition of wild-type allele signals. PMID:15251947
Cremonesi, L; Galbiati, S; Foglieni, B; Smid, M; Gambini, D; Ferrari, A; Viora, E; Campogrande, M; Pagliano, M; Travi, M; Piga, A; Restagno, G; Ferrari, M
[Hereditary neuropathy: variety of disease-causing genes and progress of molecular genetic diagnosis].
Inherited neuropathies are clinically and genetically heterogeneous. At least 30 genes have been associated with Charcot-Marie-Tooth disease (CMT) and related inherited neuropathies. Genetic studies have revealed that abnormalities in the following factors are the cause of inherited neuropathies: myelin components, transcription factors controlling myelination, myelin maintenance system, differentiation factors related to the peripheral nerve, neurofilaments, protein transfer system, mitochondrial proteins, DNA repair, RNA/protein synthesis, ion channels, and aminoacyl-tRNA synthetase. On the other hand, a precise molecular diagnosis is often needed to confirm a clinical diagnosis, offer genetic counseling to the patient and family, and provide prognostic information to the patient. Unfortunately, along with the increase in the number of genes that must be screened for mutations, the labor and reagent costs of molecular genetic testing have increased significantly. On the basis of the recent progress of DNA analysis methods, the use of resequencing microarray seems to be an economical and highly sensitive method to detect mutations. In this study, we attempted to screen for CMT patients mutations using these methods. PMID:21613657
Hashiguchi, Akihiro; Takashima, Hiroshi
Niacin and biosynthesis of PGD?by platelet COX-1 in mice and humans.
The clinical use of niacin to treat dyslipidemic conditions is limited by noxious side effects, most commonly facial flushing. In mice, niacin-induced flushing results from COX-1-dependent formation of PGD? and PGE? followed by COX-2-dependent production of PGE?. Consistent with this, niacin-induced flushing in humans is attenuated when niacin is combined with an antagonist of the PGD? receptor DP1. NSAID-mediated suppression of COX-2-derived PGI? has negative cardiovascular consequences, yet little is known about the cardiovascular biology of PGD?. Here, we show that PGD? biosynthesis is augmented during platelet activation in humans and, although vascular expression of DP1 is conserved between humans and mice, platelet DP1 is not present in mice. Despite this, DP1 deletion in mice augmented aneurysm formation and the hypertensive response to Ang II and accelerated atherogenesis and thrombogenesis. Furthermore, COX inhibitors in humans, as well as platelet depletion, COX-1 knockdown, and COX-2 deletion in mice, revealed that niacin evoked platelet COX-1-derived PGD? biosynthesis. Finally, ADP-induced spreading on fibrinogen was augmented by niacin in washed human platelets, coincident with increased thromboxane (Tx) formation. However, in platelet-rich plasma, where formation of both Tx and PGD? was increased, spreading was not as pronounced and was inhibited by DP1 activation. Thus, PGD?, like PGI?, may function as a homeostatic response to thrombogenic and hypertensive stimuli and may have particular relevance as a constraint on platelets during niacin therapy. PMID:22406532
Song, Wen-Liang; Stubbe, Jane; Ricciotti, Emanuela; Alamuddin, Naji; Ibrahim, Salam; Crichton, Irene; Prempeh, Maxwell; Lawson, John A; Wilensky, Robert L; Rasmussen, Lars Melholt; Pur�, Ellen; FitzGerald, Garret A
Application of Next Generation Sequencing Upon the Molecular Genetic Diagnosis of Deafness
The main objective of this review is to describe the new sequencing technologies called next generation sequencing (NGS) and its utility as a molecular genetic diagnosis tool in a medical field. Sanger method has dominated the genome sequencing industry for the past 30 years since its invention in 1975. It produced first human genome and still remains the gold standard for genome sequencing. However, it cannot meet the needs for enormous genetic data gathering and process because of its relatively long sequencing time and high cost per sample. NGS which parallelise the sequencing process, thereby increasing processing speed at a reduced cost per sample emerged to compensate for the weakness of the previous method. Currently NGS is used in some medical areas and its use is being widened. NGS also plays an important role in a study of genetically heterogenous hearing diseases. NGS is expected to mark a significant milestone in genomic research filed in a near future.
Kim, Bong Jik
[Clinical genetics in The Netherlands. I. Organization, activities and laboratory diagnosis].
There are seven centres for clinical genetics in the Netherlands. In 1996, some 63,000 persons (patients and possible carriers of hereditary diseases) were tested. In centres for clinical genetics chromosomal studies, biochemical diagnostics of hereditary metabolic diseases and DNA diagnostics are integrated with genetic counseling and prenatal diagnosis. The borders between the three different forms of laboratory testing for congenital anomalies and hereditary diseases gradually diminish. The variations of the numbers of laboratory examinations, genetic advices and prenatal diagnoses over the last ten years show that there is no correlation between these activities and the method of funding. Owing to the low prevalence of the diseases involved, the total number of DNA diagnoses for monogenic diseases will not increase significantly. However, once genetic risk factors of diseases such as cancer, cardiovascular diseases, diabetes, asthma, rheumatism, some psychiatric disorders and Alzheimer dementia will have been mapped, DNA diagnostics will greatly expand and will have implications in a broad area of medicine. PMID:9554157
Galjaard, H
First experiences with genetic counselling based on predictive DNA diagnosis in hereditary glomus tumours (paragangliomas).
Hereditary glomus tumour (MIM 168,000) or paraganglioma (PGL) is a slowly progressive disorder causing benign tumour growth predominantly in the head and neck region. Though benign in nature the tumours can lead to severe morbidity. Inheritance of PGL is autosomal dominant and is strongly modified by genomic imprinting; only a paternally transmitted PGL gene leads to symptoms. A gene for PGL has recently been mapped to 11q22.3-q23. Genetic counselling on the basis of DNA linkage diagnosis was offered in an extended Dutch pedigree. Thirty-two subjects opted for further counselling, of whom 20 applied for DNA testing and participated in a standardised protocol. Sixteen cases had presymptomatic testing (paternal allele); four of these appeared to have the at risk haplotype and in two of them a glomus tumour was subsequently detected on MRI. In one case linkage results were inconclusive (recombination) and one person did not want to learn his test result. Four cases had testing for carrier status (maternal allele) of which one appeared to be a carrier. Our data show that genetic counselling gains significant accuracy when based on parent of origin, sex of the counsellee, and DNA linkage diagnosis. Moreover, a normal DNA result may prevent unnecessary worry and investigations, while an established presymptomatic diagnosis will guide adequate clinical management. The psychological impact of counselling and predictive DNA testing is unclear as yet. Further investigations into the natural history of PGL in gene carriers and into the psychological impact of DNA testing is desirable.
Oosterwijk, J C; Jansen, J C; van Schothorst, E M; Oosterhof, A W; Devilee, P; Bakker, E; Zoeteweij, M W; van der Mey, A G
[Genetic analysis and prenatal diagnosis of two Chinese families with split hand foot malformation].
OBJECTIVE To identify genomic aberrations underlying pathogenesis of split hand foot malformation (SHFM) in two Chinese families, and to provide genetic counseling and prenatal diagnosis for them. METHODS Two sets of peripheral blood and amniotic fluid samples were collected from the patients. One was processed with routine culture and karyotype analysis. For another set, DNA was extracted and analyzed with array-based comparative genomic hybridization (array-CGH). RESULTS Karyotype analysis of peripheral blood samples for both probands was normal. Karyotype analysis of the amniotic fluid from family 1 has found no abnormality. However, analysis of amniotic fluid samples from the second family showed del(7)(q21q22.1). By array-CGH analysis, both blood and amniotic fluid samples from the first family showed a 662.3 kb dup(10q24.31q24.32). Array-CGH analysis of the blood sample from the second family was normal, whilst analysis of amniotic fluid sample revealed a 19.97 Mb del(7q11.23q21.3). CONCLUSION Array-CGH features high resolution, high accuracy and rapid diagnosis for unbalanced chromosomal aberration. The dup(10q24.31q24.32) and 19.97 Mb del(7q11.23q21.3) have been the cause of SHFM in the two families. Genetic counseling and prenatal diagnosis have been provided for both families in order to prevent this birth defect. PMID:24928002
Wang, Hui; Xie, Jiansheng; Chen, Wubin; Geng, Qian; Xu, Xiaoxin
The utility of exome sequencing for genetic diagnosis in a familial microcephaly epilepsy syndrome
Background Despite remarkable advances in genetic testing, many adults with syndromic epilepsy remain without a molecular diagnosis. The challenge in providing genetic testing for this patient population lies in the extensive genetic heterogeneity associated with epilepsy. Even for the subset of epilepsy patients that present with a defining feature, such as microcephaly, the number of possible genes that would require interrogation by Sanger sequencing is extensive and often prohibitively expensive. Case presentation We report a family of French Canadian descent with four adult children affected with severe intellectual disability, epilepsy and microcephaly born to consanguineous parents and evaluated by the Genetics Service to provide informed genetic counseling to unaffected family members regarding possible recurrence risks. We used whole-exome sequencing (WES) of DNA from one affected sibling as a first-line diagnostic tool and compared the prioritization of variants using two strategies: 1) focusing on genes with homozygous variants; and, 2) focusing on genes associated with microcephaly. Both approaches prioritized the same homozygous novel frameshift mutation (p.Arg608Serfs*26) in WDR62, a gene known to cause autosomal recessive primary microcephaly. Sanger sequencing confirmed the presence of the homozygous mutation in the other three affected siblings. Conclusions WES and subsequent filtering of the rare variants in a single affected family member led to the rapid and cost-effective identification of a novel homozygous frameshift mutation in WDR62, thereby explaining the severe neurodevelopmental disorder in this family and facilitating genetic counseling. Our findings support WES as an effective first-line diagnostic tool in families presenting with rare genetically heterogeneous neurological disorders.
Applications of single-strand conformation polymorphism (SSCP) to taxonomy, diagnosis, population genetics and molecular evolution of parasitic nematodes
The analysis of genetic variation in parasitic nematodes has important implications for studying aspects of taxonomy, diagnosis, population genetics, drug resistance and molecular evolution. This article highlights some applications of PCR-based single-strand conformation polymorphism (SSCP) for the analysis of sequence variation in individual parasites (and their populations) to address some of these areas. It also describes the principles and advantages
Robin B. Gasser; Neil B. Chilton
The Fault Diagnosis for Electro-Hydraulic Servo Valve Based on the Improved Genetic Neural Network Algorithm
The paper analyzes the merits and drawbacks of the genetic algorithm and BP neural network, combines with the improved genetic algorithm and BP neural network to obtain a new algorithm. The new algorithm is used in the fault diagnosis of electro-hydraulic servo valve and justified its validity, accuracy and rapidity by experiment. The BP algorithm, the conventional GA-BP algorithm and
Lian-Dong Fu; KuI-Sheng Chen; Jun-Sheng Yu; Liang-Cai Zeng
Development of screening assays and discovery of initial inhibitors of pneumococcal peptidoglycan deacetylase PgdA
The essential cell wall peptidoglycan is the target of several components of the innate immune system and its disruption results in lysis of invading bacteria. The pathogen Streptococcus pneumoniae produces a peptidoglycan N-acetylglucosamine deacetylase, PgdA, to modify the peptidoglycan structure. The activity of PgdA contributes to the bacteria's resistance to lysozyme, which is an important antimicrobial factor of the human
Nhat Khai Bui; Samo Turk; Stephan Buckenmaier; Flint Stevenson-Jones; Benjamin Zeuch; Stanislav Gobec; Waldemar Vollmer
PGD to reduce reproductive risk: the case of mitochondrial DNA disorders
This paper discusses the pros and cons of introducing PGD for mitochondrial DNA (mtDNA) disorders such as NARP (Neurogenic muscle weakness, Ataxia, Retinis Pigmentosa)\\/Leigh, MELAS (Mitochondrial myopathy, Encephalo- pathy, Lactic acidosis, and Stroke-like episodes), private mtDNA mutations and LHON (Leber Hereditary Optic Neuropathy). Although there is little experience with PGD for mtDNA disorders, it is reasonable to assume that in
A. L. Bredenoord; W. Dondorp; G. Pennings; C. E. M. De Die-Smulders; G. De Wert
Hyperornithinaemia-hyperammonaemia-homocitrullinuria syndrome: a treatable genetic liver disease warranting urgent diagnosis.
Hyperornithinaemia-hyperammonaemia-homocitrullinuria syndrome is an autosomal recessive disorder caused by a defect in ornithine translocase. This condition leads to variable clinical presentations, including episodic hyperammonaemia, hepatic derangement, and chronic neurological manifestations. Fewer than 100 affected patients have been reported worldwide. Here we report the first two cases in Hong Kong Chinese, who were compound heterozygous siblings for c.535C>T (p.Arg179*) and c.815C>T (p.Thr272Ile) in the SLC25A15 gene. When the mother refused prenatal diagnosis for the second pregnancy, urgent genetic testing provided the definitive diagnosis within 24 hours to enable specific treatment. Optimal management of these two patients relied on the concerted efforts of a multidisciplinary team and illustrates the importance of an expanded newborn screening service for early detection and treatment of inherited metabolic diseases. PMID:24473688
Lee, Hencher H C; Poon, K H; Lai, C K; Au, K M; Siu, T S; Lai, Judy P S; Mak, Chloe M; Yuen, Y P; Lam, C W; Chan, Albert Y W
Preimplantation genetic diagnosis with HLA matching - a way to save a child.
Preimplantation genetic diagnosis can be used to establish a pregnancy with an embryo that is human leukocyte antigen (HLA)-matched to a sibling having a hematological or immunological disease and needing a life-saving bone marrow transplantation. The ethical aspects of this procedure have been discussed intensively. The procedure applies where no unrelated HLA-matching donor is available or when transplantation from an HLA-matching sibling is considered a better solution. It is only offered in a limited number of centers in Europe as this is a challenging procedure. Where both HLA matching and diagnosis of a dominant disease are necessary, only a small proportion of the embryos can be used, and the procedure is not always technically feasible. The clinical pregnancy rate per cycle started is much lower than following normal in vitro fertilization (IVF) due to a high cycle cancellation rate, but the success rate is only somewhat lower when measured per transfer. PMID:22524201
Ingerslev, Hans Jakob; Hindkjaer, Johnny
An intelligent system for lung cancer diagnosis using a new genetic algorithm based feature selection method.
In this paper, we develop a novel feature selection algorithm based on the genetic algorithm (GA) using a specifically devised trace-based separability criterion. According to the scores of class separability and variable separability, this criterion measures the significance of feature subset, independent of any specific classification. In addition, a mutual information matrix between variables is used as features for classification, and no prior knowledge about the cardinality of feature subset is required. Experiments are performed by using a standard lung cancer dataset. The obtained solutions are verified with three different classifiers, including the support vector machine (SVM), the back-propagation neural network (BPNN), and the K-nearest neighbor (KNN), and compared with those obtained by the whole feature set, the F-score and the correlation-based feature selection methods. The comparison results show that the proposed intelligent system has a good diagnosis performance and can be used as a promising tool for lung cancer diagnosis. PMID:24994515
Lu, Chunhong; Zhu, Zhaomin; Gu, Xiaofeng
Tuberculosis disease diagnosis using artificial neural network trained with genetic algorithm.
Tuberculosis is a common and often deadly infectious disease caused by mycobacterium; in humans it is mainly Mycobacterium tuberculosis (Wikipedia 2009). It is a great problem for most developing countries because of the low diagnosis and treatment opportunities. Tuberculosis has the highest mortality level among the diseases caused by a single type of microorganism. Thus, tuberculosis is a great health concern all over the world, and in Turkey as well. This article presents a study on tuberculosis diagnosis, carried out with the help of multilayer neural networks (MLNNs). For this purpose, an MLNN with two hidden layers and a genetic algorithm for training algorithm has been used. The tuberculosis dataset was taken from a state hospital's database, based on patient's epicrisis reports. PMID:20703557
Elveren, Erhan; Yumu?ak, Nejat
Preimplantation genetic diagnosis for HLA typing in a case of X-linked chronic granulomatous disease.
Bone marrow transplantation may be life saving in cases of hematopoietic disease, severe congenital immunodeficiency or malignancy. An HLA-matching sibling often gives the best success, but this may not be an option, nor may an HLA-matching unrelated donor be found. Preimplantation genetic diagnosis with HLA-matching embryos may then be a solution. We report the first Danish child born after such diagnosis with identification of healthy embryos and HLA matching for a sibling with chronic granulomatous disease. Our patient had 13 in vitro fertilization (IVF) cycles; 286 oocytes were collected and 74 embryos analysed. Sixteen of these (22%) were either healthy or carriers. Five embryos were transferred in four stimulated fresh IVF cycles. Four embryos were frozen, and two were later transferred. Two successive clinical pregnancies ensued. In the first, prenatal diagnosis revealed trisomy 21, and the fetus was aborted. In the second pregnancy, chorionic villus sampling revealed a normal karyotype, the diagnosis was confirmed, and the pregnancy was normal. At delivery, 82 mL of cord blood was collected for later transplantation to the diseased sibling. PMID:22404048
Degn, Birte; Hindkjaer, Johnny; Christensen, Mette Wulff; Mortensen, Tanja �sterlund; Ingerslev, Hans Jakob
Application of massively parallel sequencing to genetic diagnosis in multiplex families with idiopathic sensorineural hearing impairment.
Despite the clinical utility of genetic diagnosis to address idiopathic sensorineural hearing impairment (SNHI), the current strategy for screening mutations via Sanger sequencing suffers from the limitation that only a limited number of DNA fragments associated with common deafness mutations can be genotyped. Consequently, a definitive genetic diagnosis cannot be achieved in many families with discernible family history. To investigate the diagnostic utility of massively parallel sequencing (MPS), we applied the MPS technique to 12 multiplex families with idiopathic SNHI in which common deafness mutations had previously been ruled out. NimbleGen sequence capture array was designed to target all protein coding sequences (CDSs) and 100 bp of the flanking sequence of 80 common deafness genes. We performed MPS on the Illumina HiSeq2000, and applied BWA, SAMtools, Picard, GATK, Variant Tools, ANNOVAR, and IGV for bioinformatics analyses. Initial data filtering with allele frequencies (<5% in the 1000 Genomes Project and 5400 NHLBI exomes) and PolyPhen2/SIFT scores (>0.95) prioritized 5 indels (insertions/deletions) and 36 missense variants in the 12 multiplex families. After further validation by Sanger sequencing, segregation pattern, and evolutionary conservation of amino acid residues, we identified 4 variants in 4 different genes, which might lead to SNHI in 4 families compatible with autosomal dominant inheritance. These included GJB2 p.R75Q, MYO7A p.T381M, KCNQ4 p.S680F, and MYH9 p.E1256K. Among them, KCNQ4 p.S680F and MYH9 p.E1256K were novel. In conclusion, MPS allows genetic diagnosis in multiplex families with idiopathic SNHI by detecting mutations in relatively uncommon deafness genes. PMID:23451214
Wu, Chen-Chi; Lin, Yin-Hung; Lu, Ying-Chang; Chen, Pei-Jer; Yang, Wei-Shiung; Hsu, Chuan-Jen; Chen, Pei-Lung
[Familial Mediterranean fever with pulmonary manifestations alone; early diagnosis with genetic analysis].
Painful pleural effusion and fever are the only presenting clinical features in 5-10% of patients with familial Mediterranean fever (FMF). We report the results of genetic analysis that have confirmed the diagnosis of FMF in six patients who presented with fever and pleuritic pain alone. At time of presentation, all six patients received antibiotic treatment for suspected infectious etiology following routine laboratory and microbiologic evaluation. Gene analysis was performed when other diagnostic studies had failed to uncover the etiology and patients did not respond to conventional treatment. Mutation analysis for MEFV gene performed from genomic DNA by the direct DNA sequence method. Half of the patients were male. Five were older than 50, one was 33 years old. All of the patients had fever and pleuritic pain; none had the typical abdominal symptoms. Erythrocyte sedimentation rates and C-reactive protein levels were high. Pericardial effusion was discovered in three patients. Genetic analysis confirmed; R202Q/R202R, E148V/E148E, R314R, E474E, Q476Q, D510D, E148Q/E148E heterozygote polymorphisms with and M694V/M694V mutations were determined on the MEFV gene. In five patients an improvement has been observed with colchicine therapy. In one patient steroid treatment was needed because of no response to colchicine and clinical deterioration. Rapid improvement was observed in this case with steroid therapy. But after cessation of steroid therapy new flare developed that responded to new colchicine therapy. In patients who present with pleuritic chest pain and fever without an identifiable etiology, genetic analysis help making the diagnosis of FMF, especially in certain ethnic populations where FMF is relevant. This should help patients receive specific treatment without unnecessary delay. Thus, by making early diagnosis and timely delivery of treatment, disease progression is delayed and development of secondary amyloidosis avoided. PMID:23289470
Sever, Fidan; Sever, Mustafa; Sanal, Salahattin; Yal�?n, Murat; Berdeli, Afig
Application of Massively Parallel Sequencing to Genetic Diagnosis in Multiplex Families with Idiopathic Sensorineural Hearing Impairment
Despite the clinical utility of genetic diagnosis to address idiopathic sensorineural hearing impairment (SNHI), the current strategy for screening mutations via Sanger sequencing suffers from the limitation that only a limited number of DNA fragments associated with common deafness mutations can be genotyped. Consequently, a definitive genetic diagnosis cannot be achieved in many families with discernible family history. To investigate the diagnostic utility of massively parallel sequencing (MPS), we applied the MPS technique to 12 multiplex families with idiopathic SNHI in which common deafness mutations had previously been ruled out. NimbleGen sequence capture array was designed to target all protein coding sequences (CDSs) and 100 bp of the flanking sequence of 80 common deafness genes. We performed MPS on the Illumina HiSeq2000, and applied BWA, SAMtools, Picard, GATK, Variant Tools, ANNOVAR, and IGV for bioinformatics analyses. Initial data filtering with allele frequencies (<5% in the 1000 Genomes Project and 5400 NHLBI exomes) and PolyPhen2/SIFT scores (>0.95) prioritized 5 indels (insertions/deletions) and 36 missense variants in the 12 multiplex families. After further validation by Sanger sequencing, segregation pattern, and evolutionary conservation of amino acid residues, we identified 4 variants in 4 different genes, which might lead to SNHI in 4 families compatible with autosomal dominant inheritance. These included GJB2 p.R75Q, MYO7A p.T381M, KCNQ4 p.S680F, and MYH9 p.E1256K. Among them, KCNQ4 p.S680F and MYH9 p.E1256K were novel. In conclusion, MPS allows genetic diagnosis in multiplex families with idiopathic SNHI by detecting mutations in relatively uncommon deafness genes.
A modified I-PCR to detect the factor VIII Inv22 for genetic diagnosis and prenatal diagnosis in haemophilia A.
To explore the effectiveness of modified inversion-polymerase chain reaction (I-PCR) to detect the factor VIII (FVIII) intron 22 inversion (Inv22) for genetic diagnosis and prenatal diagnosis in haemophilia A (HA). Both modified I-PCR and LD-PCR were applied to analyse the FVIII Inv22 for 24 patients with HA. Prenatal diagnosis was performed on six foetuses. Foetal blood samplings were carried out by cordocentesis from 22 to 26 weeks of gestation. Ten patients with FVIII Inv22 in 10 HA families were found, and the remaining 14 patients were found without the Inv22 in 19 HA families. Prenatal diagnosis confirmed that four foetuses were normal and all of them born normally. However, two foetuses had been identified as abnormal and undergone abortion. Compared with LD-PCR, modified I-PCR is more rapid and convenient for detecting the FVIII Inv22 in genetic diagnosis. It is recommended that a patient undergoes both modified I-PCR (to detect the FVIII Inv22) and biochemical assay (to measure the FVIII activity of umbilical cord blood) in prenatal diagnosis. When we have more experience, the DNA samples from chorionic villus or amniotic fluid can be analysed for prenatal diagnosis using the modified I-PCR alone. PMID:21992753
He, Z H; Chen, S F; Chen, J; Jiang, W Y
PGD to reduce reproductive risk: the case of mitochondrial DNA disorders.
This paper discusses the pros and cons of introducing PGD for mitochondrial DNA (mtDNA) disorders such as NARP (Neurogenic muscle weakness, Ataxia, Retinis Pigmentosa)/Leigh, MELAS (Mitochondrial myopathy, Encephalopathy, Lactic acidosis, and Stroke-like episodes), private mtDNA mutations and LHON (Leber Hereditary Optic Neuropathy). Although there is little experience with PGD for mtDNA disorders, it is reasonable to assume that in many cases, the best one can achieve is the selection of the 'least' affected embryos for transfer. So instead of 'promising' parents a healthy child, PGD in these cases can only aim at reducing reproductive risk. From an ethical point of view, this raises challenging questions about parental and medical responsibilities. The main argument in favour of PGD is that it offers couples at risk the opportunity of reducing their chances of having a severely affected child. Potential objections are manifold, but we conclude that none of them supplies convincing moral arguments to regard risk-reducing PGD as unacceptable. Nevertheless, introducing this new application of PGD in clinical practice will raise further complex issues of determining conditions for its responsible use. PMID:18664474
Bredenoord, A L; Dondorp, W; Pennings, G; De Die-Smulders, C E M; De Wert, G
Prenatal diagnosis of genetic disease in Canada: report of a collaborative study.
A study of 1223 amniocenteses carried out during 1020 pregnancies in 990 women showed that 2nd-trimester amniocentesis at about 16 weeks' gestation is a safe, accurate and reliable procedure for the diagnosis of certain classes of genetic disease when it is monitored by ultrasound, performed by a trained obstetrician and carried out in a major health sciences centre. The percentage of fetal losses (4.7%) and neonatal deaths (0.5%) during the study was not greater than in control samples for women 35 years of age and older. The best results were obtained when needles of gauge 20 or 21 were used. The use of needles of gauge 19 or larger and more than two insertions during a single amniocentesis were associated with a significantly greater frequency of fetal loss than a second or even a third amniocentesis during the same pregnancy. For 39 fetuses (3.8%) a diagnosis of a genetic abnormality was made and 23 male fetuses were found to be potentially hemizygous for an X-linked gene. There were 51 therapeutic abortions as a result of the diagnosis. Sixty-six tests (5.4%) gave an inconclusive result and seven (0.6%) gave an erroneous diagnosis; five of the latter (two false-positives and three false-negatives) resulted from the alpha1-fetoprotein test for neural-tube defects and in two cases the sex was incorrectly determined. The frequency of all chromosome abnormalities was 1:20 when the mother's age was 40 years or more and 1:60 when the mother's age was between 35 and 39 years. When a mother had previously had a child with a chromosome abnormality the risk of recurrence of such an abnormality was 1:100 when the age of the mother was 35 years or more.
Simpson, N. E.; Dallaire, L.; Miller, J. R.; Siminovich, L.; Hamerton, J. L.; Miller, J.; McKeen, C.
Bach to the future: response to: Extending preimplantation genetic diagnosis: medical and non-medical uses.
Professor Robertson sketches an elegant framework for policy evaluation and regulation of the use of preimplantation genetic diagnosis for various medical, medical related, and non-medical purposes. In criticism of his position, I argue that the distinction between policy and ethics upon which his argument relies is highly unstable, and the approach taken to ethical evaluation of particular parental interests leaves open many issues which the policy approach would hope to exclude. In conclusion I argue that while his position ultimately fails, the onus is on his critics to come up with a viable and satisfying alternative. PMID:12930853
Ashcroft, R
A Genetic Algorithm-Based Neural Network Approach for Fault Diagnosis in Hydraulic Servo-Valves
\\u000a The hydraulic servo-valve is the key component of the electro-hydraulic system. But it is difficult to diagnose faults in\\u000a a hydraulic servo-valve. In this paper, a Genetic Algorithm-based Artificial Neural Network model for fault diagnosis in hydraulic\\u000a servo�valves is proposed. We use a known set of servo-valve faults as the outputs to the valve-behavior model. Adoption of\\u000a this approach brings
Hao Huang; Kuisheng Chen; Liangcai Zeng
New advances of preimplantation and prenatal genetic screening and noninvasive testing as a potential predictor of health status of babies.
The current morphologically based selection of human embryos for transfer cannot detect chromosome aneuploidies. So far, only biopsy techniques have been able to screen for chromosomal aneuploidies in the in vitro fertilization (IVF) embryos. Preimplantation genetic diagnosis (PGD) or screening (PGS) involves the biopsy of oocyte polar bodies or embryonic cells and has become a routine clinical procedure in many IVF clinics worldwide, including recent development of comprehensive chromosome screening of all 23 pairs of chromosomes by microarrays for aneuploidy screening. The routine preimplantation and prenatal genetic diagnosis (PND) require testing in an aggressive manner. These procedures may be invasive to the growing embryo and fetus and potentially could compromise the clinical outcome. Therefore the aim of this review is to summarize not only the new knowledge on preimplantation and prenatal genetic diagnosis in humans, but also on the development of potential noninvasive embryo and fetal testing that might play an important role in the future. PMID:24783200
Milachich, Tanya
Current issues in medically assisted reproduction and genetics in Europe: research, clinical practice, ethics, legal issues and policy. European Society of Human Genetics and European Society of Human Reproduction and Embryology.
In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and assisted reproductive technology (ART), and published an extended background paper, recommendations and two Editorials. Seven years later, in March 2012, a follow-up interdisciplinary workshop was held, involving representatives of both professional societies, including experts from the European Union Eurogentest2 Coordination Action Project. The main goal of this meeting was to discuss developments at the interface between clinical genetics and ARTs. As more genetic causes of reproductive failure are now recognised and an increasing number of patients undergo testing of their genome before conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and preimplantation genetic diagnosis (PGD) may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from randomised clinical trials to substantiate that the technique is both effective and efficient. Whole-genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (International Standards Organisation - ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. The legal landscape regarding assisted reproduction is evolving but still remains very heterogeneous and often contradictory. The lack of legal harmonisation and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe and beyond. The aim of this paper is to complement previous publications and provide an update of selected topics that have evolved since 2005. PMID:24225486
Harper, Joyce C; Geraedts, Joep; Borry, Pascal; Cornel, Martina C; Dondorp, Wybo; Gianaroli, Luca; Harton, Gary; Milachich, Tanya; K��ri�inen, Helena; Liebaers, Inge; Morris, Michael; Sequeiros, Jorge; Sermon, Karen; Shenfield, Fran�oise; Skirton, Heather; Soini, Sirpa; Spits, Claudia; Veiga, Anna; Vermeesch, Joris Robert; Viville, St�phane; de Wert, Guido; Macek, Milan
Current issues in medically assisted reproduction and genetics in Europe: research, clinical practice, ethics, legal issues and policy
In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and assisted reproductive technology (ART), and published an extended background paper, recommendations and two Editorials. Seven years later, in March 2012, a follow-up interdisciplinary workshop was held, involving representatives of both professional societies, including experts from the European Union Eurogentest2 Coordination Action Project. The main goal of this meeting was to discuss developments at the interface between clinical genetics and ARTs. As more genetic causes of reproductive failure are now recognised and an increasing number of patients undergo testing of their genome before conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and preimplantation genetic diagnosis (PGD) may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from randomised clinical trials to substantiate that the technique is both effective and efficient. Whole-genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (International Standards Organisation � ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. The legal landscape regarding assisted reproduction is evolving but still remains very heterogeneous and often contradictory. The lack of legal harmonisation and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe and beyond. The aim of this paper is to complement previous publications and provide an update of selected topics that have evolved since 2005.
Harper, Joyce C; Geraedts, Joep; Borry, Pascal; Cornel, Martina C; Dondorp, Wybo; Gianaroli, Luca; Harton, Gary; Milachich, Tanya; Kaariainen, Helena; Liebaers, Inge; Morris, Michael; Sequeiros, Jorge; Sermon, Karen; Shenfield, Francoise; Skirton, Heather; Soini, Sirpa; Spits, Claudia; Veiga, Anna; Vermeesch, Joris Robert; Viville, Stephane; de Wert, Guido; Macek, Milan
Genetic diagnosis of idiopathic hypogonadotrophic hypogonadism: a new point mutation in the KAL2 gene.
Kallmann Syndrome (KS) is a genetic disease of embryonic development which is characterized by the association of hypogonadotropic hypogonadism (HH) due to a deficit of the gonadotropin-releasing hormone (GnRH) and a hypo/anosmia (including a hypoplasia of the nasal sulcus and agenesis of the olfactory bulbs). Even though it is a genotypically and phenotypically heterogeneous clinical disease, there are some key genes related to KS (KAL1, FGFR1 (KAL2), GNRHR, KISSR1 (GPR54), GNRH1, NELF and PROK2). The aim of this study was to present a case report of a genetic diagnosis of KS linked to the presence of mutations in the FGFR1 (fibroblast growth factor receptor 1, also known as KAL2) gene. This diagnosis was made in a 44-year old female affected by a hypogonadism for which she had received intermittent treatment until she was 30 years old based on the patient's own decision. The molecular analysis of FGFR1 identified the mutation c. 246_247delAG (p.T82Xfs110) in heterozygosis on exon 3 of the KAL2 gene. This is the first report of this mutation related to idiopathic hypogonadotrophic hypogonadism (IHH). PMID:24776628
Entrala-Bernal, Carmen; Montes-Castillo, Cristina; Alvarez-Cubero, Maria Jesus; Guti�rrez-Alc�ntara, Carmen; Fernandez-Rosado, Francisco; Martinez-Esp?n, Esther; S�nchez-Malo, Carolina; Santiago-Fern�ndez, Piedad
Impact of genetics on the diagnosis and clinical management of syndromic craniosynostoses
Purpose More than 60 different mutations have been identified to be causal in syndromic forms of craniosynostosis. The majority of these mutations occur in the fibroblast growth factor receptor 2 gene (FGFR2). The clinical management of syndromic craniosynostosis varies based on the particular causal mutation. Additionally, the diagnosis of a patient with syndromic craniosynostosis is based on the clinical presentation, signs, and symptoms. The understanding of the hallmark features of particular syndromic forms of craniosynostosis leads to efficient diagnosis, management, and long-term prognosis of patients with syndromic craniosynostoses. Methods A comprehensive literature review was done with respect to the major forms of syndromic craniosynostosis and additional less common FGFR-related forms of syndromic craniosynostosis. Additionally, information and data gathered from studies performed in our own investigative lab (lab of Dr. Muenke) were further analyzed and reviewed. A literature review was also performed with regard to the genetic workup and diagnosis of patients with craniosynostosis. Results Patients with Apert syndrome (craniosynostosis syndrome due to mutations in FGFR2) are most severely affected in terms of intellectual disability, developmental delay, central nervous system anomalies, and limb anomalies. All patients with FGFR-related syndromic craniosynostosis have some degree of hearing loss that requires thorough initial evaluations and subsequent follow-up. Conclusions Patients with syndromic craniosynostosis require management and treatment of issues involving multiple organ systems which span beyond craniosynostosis. Thus, effective care of these patients requires a multidisciplinary approach.
Agochukwu, Nneamaka B.; Solomon, Benjamin D.; Muenke, Maximilian
Prenatal Diagnosis of ?-Thalassemias and Hemoglobinopathies.
Prenatal diagnosis of ?-thalassemia was accomplished for the first time in the 1970s by globin chain synthesis analysis on fetal blood obtained by placental aspiration at 18�22 weeks gestation. Since then, the molecular definition of the ?-globin gene pathology, the development of procedures of DNA analysis, and the introduction of chorionic villous sampling have dramatically improved prenatal diagnosis of this disease and of related disorders. Much information is now available about the molecular mechanisms of the diseases and the molecular testing is widespread. As prenatal diagnosis has to provide an accurate, safe and early result, an efficient screening of the population and a rapid molecular characterization of the couple at risk, are necessary prerequisites. In the last decades earlier and less invasive approaches for prenatal diagnosis were developed. A overview of the most promising procedure will be done. Moreover, in order to reduce the choice of interrupting the pregnancy in case of affected fetus, Preimplantation or Preconceptional Genetic Diagnosis (PGD) has been setting up for several diseases including thalassemias
Rosatelli, Maria Cristina; Saba, Luisella
Niacin and biosynthesis of PGD2 by platelet COX-1 in mice and humans
The clinical use of niacin to treat dyslipidemic conditions is limited by noxious side effects, most commonly facial flushing. In mice, niacin-induced flushing results from COX-1�dependent formation of PGD2 and PGE2 followed by COX-2�dependent production of PGE2. Consistent with this, niacin-induced flushing in humans is attenuated when niacin is combined with an antagonist of the PGD2 receptor DP1. NSAID-mediated suppression of COX-2�derived PGI2 has negative cardiovascular consequences, yet little is known about the cardiovascular biology of PGD2. Here, we show that PGD2 biosynthesis is augmented during platelet activation in humans and, although vascular expression of DP1 is conserved between humans and mice, platelet DP1 is not present in mice. Despite this, DP1 deletion in mice augmented aneurysm formation and the hypertensive response to Ang II and accelerated atherogenesis and thrombogenesis. Furthermore, COX inhibitors in humans, as well as platelet depletion, COX-1 knockdown, and COX-2 deletion in mice, revealed that niacin evoked platelet COX-1�derived PGD2 biosynthesis. Finally, ADP-induced spreading on fibrinogen was augmented by niacin in washed human platelets, coincident with increased thromboxane (Tx) formation. However, in platelet-rich plasma, where formation of both Tx and PGD2 was increased, spreading was not as pronounced and was inhibited by DP1 activation. Thus, PGD2, like PGI2, may function as a homeostatic response to thrombogenic and hypertensive stimuli and may have particular relevance as a constraint on platelets during niacin therapy.
Song, Wen-Liang; Stubbe, Jane; Ricciotti, Emanuela; Alamuddin, Naji; Ibrahim, Salam; Crichton, Irene; Prempeh, Maxwell; Lawson, John A.; Wilensky, Robert L.; Rasmussen, Lars Melholt; Pure, Ellen; FitzGerald, Garret A.
Genetic and epigenetic biomarkers for diagnosis, prognosis and treatment of colorectal cancer.
Colorectal cancer (CRC) is one of the most common cancer worldwide and results from the accumulation of mutations and epimutations in colonic mucosa cells ultimately leading to cell proliferation and metastasis. Unfortunately, CRC prognosis is still poor and the search of novel diagnostic and prognostic biomarkers is highly desired to prevent CRC-related deaths. The present article aims to summarize the most recent findings concerning the use of either genetic or epigenetic (mainly related to DNA methylation) biomarkers for CRC diagnosis, prognosis, and response to treatment. Recent large-scale DNA methylation studies suggest that CRC can be divided into several subtypes according to the frequency of DNA methylation and those of mutations in key CRC genes, and that this is reflected by different prognostic outcomes. Increasing evidence suggests that the analysis of DNA methylation in blood or fecal specimens could represent a valuable non-invasive diagnostic tool for CRC. Moreover, a broad spectrum of studies indicates that the inter-individual response to chemotherapeutic treatments depends on both epigenetic modifications and genetic mutations occurring in colorectal cancer cells, thereby opening the way for a personalized medicine. Overall, combining genetic and epigenetic data might represent the most promising tool for a proper diagnostic, prognostic and therapeutic approach. PMID:24574767
Copped�, Fabio; Lopomo, Angela; Spisni, Roberto; Migliore, Lucia
A model of genetic guidance for hemoglobinopathy patients and laboratory diagnosis of family members as educational and preventive measures
Background: The high frequency of hemoglobinopathies in Brazil constitutes a public health problem and thus educational and preventive measures are necessary to reduce the incidence. Genetic guidance, a modality of genetic counseling, and family screening are measures that can assist in reproductive decisions and mitigate clinical, psychological and social problems of families with these disorders. Objetive: The objective of the current study was to evaluate the effectiveness of educational and preventive measures for hemoglobinopathies using genetic guidance and laboratory screening of families. Methods: The diagnoses of patients with hemoglobinopathies were confirmed and then the level of knowledge about their disease was evaluated and genetic guidance was provided. Three months later, the level of assimilated information of these patients was evaluated. In addition, laboratory diagnosis of family members was carried out. Results: Diagnosis of sickle cell anemia was confirmed for most patients. Moreover, the majority of the patients who had a low level of knowledge before genetic guidance (68.8%) demonstrated a higher level of assimilated information after the process (81.8%). Almost 70% of the family members had hemoglobin changes and some had hemoglobinopathies(2.6%). They were duly informed about the results of the examinations, which made it possible to investigate further. Conclusion: Genetic guidance and family screening were effective preventive and educational measures that improved the quality of life of patients, preventing complications and sequels and allowed the referral of those who may transmit altered genes for clinical diagnosis and to genetic counseling services.
Ferreira, Tatiana Dela-Savia; Freire, Adriana Sousa; Silveira-Lacerda, Elisangela de Paula; Garcia-Zapata, Marco Tulio Antonio
Detection prognostically relevant genetic abnormalities childhood B-cell precursor acute lymphoblastic leukemia: recommendations Biology Diagnosis Committee International Berlin-Frankfurt.2010
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Yin-Yang regulation of prostaglandins and nitric oxide by PGD2 in human arthritis: reversal by celecoxib.
The role of PGD2 has been recognized in allergy, innate immunity and inflammation. Western blot analysis identified 21 kDa lipocalin (L)-prostaglandin D2 (PGD2) synthase (S) in human osteoarthritis (OA)-affected cartilage, whose expression was increased by IL-1? and TNF?. Similarly, PGD2 was spontaneously released by human OA-affected cartilage (and upregulated by IL-?) in ex vivo conditions and could be inhibited by indomethacin. Addition of PGD2 to human OA-affected cartilage significantly increased accumulation of PGE2, PGF1?, PGF2?, TXB2, but inhibited LTB4 and nitric oxide (NO) accumulation. Similarly, PGD2 (but not 13,14-dihydro-15-keto PGD2) augmented IL-1? induced PGE2 but inhibited IL-? induced nitric oxide (NO) in human chondrocytes. Celecoxib (10 ?M) inhibits COX-1 mediated PGD2, and nitric oxide synthase (NOS) mediated NO in human OA-affected cartilage. Furthermore, celecoxib (1 ?M) counter balances (IL-1? induced+PGD2 modulated) levels of NO and PGE2 in human OA-affected cartilage and chondrocytes to basal levels. These results show concentration-dependent, pro- and anti-inflammatory activity of PGD2 in human chondrocytes and cartilage, which can be neutralized by celecoxib. In view of the broad prostaglandin dependent and independent mechanism of action of celecoxib, these observations further reaffirm the broader role of celecoxib as a "Disease Modifying Drug" for human Osteoarthritis. PMID:23603366
Dave, Mandar; Amin, Ashok R
Permanent Neonatal Diabetes Mellitus: Prevalence and Genetic Diagnosis in the SEARCH for Diabetes in Youth Study
Background Neonatal diabetes mellitus (NDM) is defined as diabetes with onset before 6 months of age. Nearly half of individuals with NDM are affected by permanent neonatal diabetes mellitus (PNDM). Mutations in KATP channel genes (KCNJ11, ABCC8) and the insulin gene (INS) are the most common causes of PNDM. Objective To estimate the prevalence of PNDM among SEARCH for Diabetes in Youth (SEARCH) study participants (2001-2008) and to identify the genetic mutations causing PNDM. Methods SEARCH is a multi-center population-based study of diabetes in youth < 20 years of age. Participants diagnosed with diabetes before 6 months of age were invited for genetic testing for mutations in the KCNJ11, ABCC8 and INS genes. Results Of the 15,829 SEARCH participants with diabetes, 39 were diagnosed before 6 months of age. Thirty five of them had PNDM (0.22% of all diabetes cases in SEARCH), 3 had transient neonatal diabetes that had remitted by 18 months and one was unknown. The majority of them (66.7%) had a clinical diagnosis of type1 diabetes by their health care provider. Population prevalence of PNDM in youth <20 years was estimated at 1 in 252,000. Seven participants underwent genetic testing; mutations causing PNDM were identified in five (71%), (two KCNJ11, three INS). Conclusions We report the first population-based frequency of PNDM in the US based on the frequency of PNDM in SEARCH. Patients with NDM are often misclassified as having type1 diabetes. Widespread education is essential to encourage appropriate genetic testing and treatment of NDM.
Shankar, Roopa Kanakatti; Pihoker, Catherine; Dolan, Lawrence M.; Standiford, Debra; Badaru, Angela; Dabelea, Dana; Rodriguez, Beatriz; Black, Mary Helen; Imperatore, Giuseppina; Hattersley, Andrew; Ellard, Sian; Gilliam, Lisa K.
First-trimester genetic diagnosis in multiple pregnancy: principles and potential pitfalls.
Both the principles of first-trimester genetic diagnosis in multiple pregnancy and the special considerations required to avoid potential diagnostic pitfalls are presented. The experience consisted of 65 cases of twins and one case of quadruplets. Dichorionic twins were recognized by sonography in 54 cases. Transabdominal aspiration was generally preferred to transcervical for obtaining chorionic tissue, although in two cases both approaches were used. Diagnostic error following erroneous sampling was reported in 3 out of 54 sets of dichorionic twins (5.5 per cent). When like-sex dichorionic twins cannot be differentiated by cytogenetic or DNA polymorphism studies, amniocentesis should be recommended to confirm the reliability of the result on chorionic tissue. PMID:1800988
Brambati, B; Tului, L; Lanzani, A; Simoni, G; Travi, M
Molecular diagnosis reveals genetic heterogeneity for the overlapping MKKS and BBS phenotypes.
Hydrometrocolpos and polydactyly diagnosed in the prenatal period or early childhood may raise diagnostic dilemmas especially in distinguishing McKusick-Kaufman syndrome (MKKS) and the Bardet-Biedl syndrome (BBS). These two conditions can initially overlap. With time, the additional features of BBS appearing in childhood, such as retinitis pigmentosa, obesity, learning disabilities and progressive renal dysfunction allow clear differentiation between BBS and MKKS. Genotype overlap also exists, as mutations in the MKKS-BBS6 gene are found in both syndromes. We report 7 patients diagnosed in the neonatal period with hydrometrocolpos and polydactyly who carry mutations in various BBS genes (BBS6, BBS2, BBS10, BBS8 and BBS12), stressing the importance of wide BBS genotyping in patients with this clinical association for diagnosis, prognosis and genetic counselling. PMID:21044901
Schaefer, Elise; Durand, Myriam; Stoetzel, Corinne; Doray, B�r�nice; Viville, Brigitte; Hell�, Sophie; Danse, Jean-Marc; Hamel, Christian; Bitoun, Pierre; Goldenberg, Alice; Finck, Sonia; Faivre, Laurence; Sigaudy, Sabine; Holder, Muriel; Vincent, Marie-Claire; Marion, Vincent; Bonneau, Dominique; Verloes, Alain; Nisand, Isra�l; Mandel, Jean-Louis; Dollfus, H�l�ne
Feature selection from nocturnal oximetry using genetic algorithms to assist in obstructive sleep apnoea diagnosis.
Nocturnal pulse oximetry (NPO) has demonstrated to be a powerful tool to help in obstructive sleep apnoea (OSA) detection. However, additional analysis is needed to use NPO alone as an alternative to nocturnal polysomnography (NPSG), which is the gold standard for a definitive diagnosis. In the present study, we exhaustively analysed a database of blood oxygen saturation (SpO(2)) recordings (80 OSA-negative and 160 OSA-positive) to obtain further knowledge on the usefulness of NPO. Population set was randomly divided into training and test sets. A feature extraction stage was carried out: 16 features (time and frequency statistics and spectral and nonlinear features) were computed. A genetic algorithm (GA) approach was applied in the feature selection stage. Our methodology achieved 87.5% accuracy (90.6% sensitivity and 81.3% specificity) in the test set using a logistic regression (LR) classifier with a reduced number of complementary features (3 time domain statistics, 1 frequency domain statistic, 1 conventional spectral feature and 1 nonlinear feature) automatically selected by means of GAs. Our results improved diagnostic performance achieved with conventional oximetric indexes commonly used by physicians. We concluded that GAs could be an effective and robust tool to search for essential oximetric features that could enhance NPO in the context of OSA diagnosis. PMID:22154238
�lvarez, Daniel; Hornero, Roberto; Marcos, J V�ctor; Del Campo, F�lix
Functional constraints of 6-phosphogluconate dehydrogenase (6-PGD) based on sequence and structural information.
The pentose phosphate cycle is considered as a major source of NADPH and pentose needed for nucleic acid biosynthesis. 6-Phosphogluconate dehydrogenase (6PGD), an enzyme participating in this cycle, catalyzes the oxidative decarboxylation of 6PGD to ribulose 5-phosphate with the subsequent release of CO2 and the reduction of NADP. We have determined the amino acid sequence of 6PGD of Bactrocera oleae and constructed a three-dimensional model based on the homologous known sheep structure. In a comparative study of 6PGD sequences from numerous species, all the conserved and variable regions of the enzyme were analyzed and the regions of functional importance were localized, in an attempt promoted also by the direct involvement of the enzyme in various human diseases. Thus, analysis of amino acid variability of 37 6PGD sequences revealed that all regions important for the catalytic activity, such as those forming the substrate and coenzyme binding sites, are highly conserved in all species examined. Moreover, several amino acid residues responsible for substrate and coenzyme specificity were also found to be identical in all species examined. The higher percentage of protein divergence is observed at two regions that accumulate mutations, located at the distant parts of the two domains of the enzyme with respect to their interface. These peripheral regions of non-functional importance are highly variable and are predicted as antigenic, thus reflecting possible regions for antibody recognition. Furthermore, locating the differences between diptera 6PGD sequences on the three-dimensional model suggests probable positions of different amino acid residues appearing at B. oleae fast, intermediate, and slow allozymic variants. PMID:15553090
Goulielmos, George N; Eliopoulos, Elias; Loukas, Michael; Tsakas, Spyros
Differential diagnosis of type 1 diabetes: which genetic syndromes need to be considered?
Recently it has become apparent that not all diabetes presenting in childhood is type 1. Increasingly type 2 diabetes, secondary diabetes, maturity onset diabetes of the young, and rare syndromic forms of diabetes such as Wolfram syndrome and Alstrom syndrome have been identified in children. Although individually rare, collectively they make up about 5% of children seen in diabetes clinics. The importance of these syndromes for children lies in the recognition of treatable complications, and for their parents, the possibility of genetic counselling. The scientific importance is enormous as they are experiments of nature that reveal basic mechanisms of insulin and glucose metabolism. We are now able to offer mutation analysis to correlate the clinical pattern to the genotype, and seek novel therapeutic approaches based on the developing knowledge of gene and protein functions. This review focuses on monogenic syndromes of diabetes, particularly where significant advances have been made in our understanding recently. Neonatal diabetes is a specialist field in its own right and is not included, except to discuss Kir6.2 diabetes which may develop in infancy. This review is written for the paediatric diabetes specialist and aims to provide information on the clinical features, natural history, genetics and management of children with diabetes as part of a syndrome. Finally there is information on useful investigations to aid diagnosis. PMID:17727381
Barrett, Timothy Geoffrey
Diabetes Mellitus in Neonates and Infants: Genetic Heterogeneity, Clinical Approach to Diagnosis, and Therapeutic Options
Over the last decade, we have witnessed major advances in the understanding of the molecular basis of neonatal and infancy-onset diabetes. It is now widely accepted that diabetes presenting before 6 months of age is unlikely to be autoimmune type 1 diabetes. The vast majority of such patients will have a monogenic disorder responsible for the disease and, in some of them, also for a number of other associated extrapancreatic clinical features. Reaching a molecular diagnosis will have immediate clinical consequences for about half of affected patients, as identification of a mutation in either of the two genes encoding the ATP-sensitive potassium channel allows switching from insulin injections to oral sulphonylureas. It also facilitates genetic counselling within the affected families and predicts clinical prognosis. Importantly, monogenic diabetes seems not to be limited to the first 6 months but extends to some extent into the second half of the first year of life, when type 1 diabetes is the more common cause of diabetes. From a scientific perspective, the identification of novel genetic aetiologies has provided important new knowledge regarding the development and function of the human pancreas.
Rubio-Cabezas, Oscar; Ellard, Sian
Proper general decomposition (PGD) for the resolution of Navier-Stokes equations
In this work, the PGD method will be considered for solving some problems of fluid mechanics by looking for the solution as a sum of tensor product functions. In the first stage, the equations of Stokes and Burgers will be solved. Then, we will solve the Navier-Stokes problem in the case of the lid-driven cavity for different Reynolds numbers ( Re = 100, 1000 and 10,000). Finally, the PGD method will be compared to the standard resolution technique, both in terms of CPU time and accuracy.
Dumon, A.; Allery, C.; Ammar, A.
Attitudes towards Genetic Diagnosis in Pakistan: A Survey of Medical and Legal Communities and Parents of Thalassemic Children
Objectives: It was the aim of this study to assess the attitudes of doctors, medical students, lawyers, parliament members and parents of thalassemic children towards genetic diagnosis in Pakistan. Study Design: A cross-sectional descriptive survey was conducted among representative samples. Results: Five hundred and seventy doctors, 49 lawyers, 178 medical students, 89 parents of thalassemic children and 16 members of
Ahmed I. Gilani; Atif S. Jadoon; Rabia Qaiser; Sana Nasim; Riffat Meraj; Nosheen Nasir; Fizza F. Naqvi; Zafar Latif; Muhammad A. Memon; Esme V. Menezes; Imran Malik; Muhammad Z. Memon; Syed F. Kazim; Usman Ahmad
Use of the MLPA Assay in the Molecular Diagnosis of Gene Copy Number Alterations in Human Genetic Diseases
Multiplex Ligation-dependent Probe Amplification (MLPA) assay is a recently developed technique able to evidence variations in the copy number of several human genes. Due to this ability, MLPA can be used in the molecular diagnosis of several genetic diseases whose pathogenesis is related to the presence of deletions or duplications of specific genes. Moreover, MLPA assay can also be used in the molecular diagnosis of genetic diseases characterized by the presence of abnormal DNA methylation. Due to the large number of genes that can be analyzed by a single technique, MLPA assay represents the gold standard for molecular analysis of all pathologies derived from the presence of gene copy number variation. In this review, the main applications of the MLPA technique for the molecular diagnosis of human diseases are described.
Stuppia, Liborio; Antonucci, Ivana; Palka, Giandomenico; Gatta, Valentina
Use of the MLPA Assay in the Molecular Diagnosis of Gene Copy Number Alterations in Human Genetic Diseases.
Multiplex Ligation-dependent Probe Amplification (MLPA) assay is a recently developed technique able to evidence variations in the copy number of several human genes. Due to this ability, MLPA can be used in the molecular diagnosis of several genetic diseases whose pathogenesis is related to the presence of deletions or duplications of specific genes. Moreover, MLPA assay can also be used in the molecular diagnosis of genetic diseases characterized by the presence of abnormal DNA methylation. Due to the large number of genes that can be analyzed by a single technique, MLPA assay represents the gold standard for molecular analysis of all pathologies derived from the presence of gene copy number variation. In this review, the main applications of the MLPA technique for the molecular diagnosis of human diseases are described. PMID:22489151
Neuropsychopharmacology and the genetics of schizophrenia: a history of the diagnosis of schizophrenia.
Development of the diagnostic concept of schizophrenia (dementia praecox) is traced from the fourth edition of [Kraepelin, E., 1893. Ein Kurzes Lehrbuch der Psychiatrie. 4 Aufl. Barth, Lepzig] textbook to the DSM-IV [American Psychiatric Association, 1994. Diagnostic and Statistical Manual of Mental Disorders. Fourth ed. American Psychiatric Association, Washington, 273-316]. The differences between the criteria used by Bleuler [Bleuler, E., 1911. Dementia Praecox oder Gruppe der Schizophrenien. Deuticke, Leipzig] and Schneider [Fortschr. Neurol. Psychiatr. 25 (1957) 487] in the diagnosis of schizophrenia are discussed. The nosologic contributions of Kleist [Klin. Wochenschr. 2 (1923) 962] and Leonhard [Leonhard, K., 1957. Aufteilung der endogenen Psychosen. Akademie, Berlin]--which split schizophrenia into two major classes of disease with several forms and subforms--are outlined. Epidemiological findings--which show wide variations in the prevalence of schizophrenia in the general population and in the admission rate of schizophrenics to psychiatric clinics--are presented. Findings in genetic studies are reviewed with special reference to family, twin, and adoption studies which have raised the possibility that heredity plays an important role in the etiology of schizophrenia; mathematical analyses are examined which have ruled out monogenic transmission, as well as molecular genetic investigations indicating that the schizophrenic population is genetically heterogeneous. The relevance of findings with endophenotypes to the genetics of schizophrenia is questioned. The history of pharmacotherapy, neuropharmacology, and psychopharmacology of schizophrenia is outlined. Attention is focused on findings which indicate that the schizophrenic population is pharmacologically heterogenous. It is emphasized that neuropsychopharmacology, through its unique capability of linking the effects of psychotropic drugs to brain structures--encoded by genes which have been identified--offers a pioneering methodology for bridging the gap between the genes and psychiatric nosology. It is pointed out that for the detection of subpopulations within schizophrenia, clinical investigations with antipsychotic drugs have to proceed beyond the demonstration of therapeutic efficacy to the identification of treatment-responsive form(s) of illness. Early findings by Fish [L'Encephale 53 (1964) 245] are presented which indicate that affect-laden paraphrenia, one of the three forms of unsystematic schizophrenia in Leonhard [Leonhard, K., 1957. Aufteilung der endogenen Psychosen. Akademie, Berlin] classification, is the treatment-responsive subpopulation within schizophrenia for typical antipsychotic drugs. It is suggested that if the findings of Fish [L'Encephale 53 (1964) 245] could be verified, affect-laden paraphrenia would qualify for molecular genetic research. Another possible subpopulation that might qualify for genetic research is systematic hebephrenia, one of the three forms of systematic hebephrenia. The paper concludes that resolving the heterogeneity of the schizophrenic population would open up a new perspective for genetic research and for the pharmacotherapy of the different illnesses covered up for a century by the diagnostic label of schizophrenia. PMID:15363601
Ban, Thomas A
Response of the G6pd and 6Pgd polymorphisms in Drosophila melanogaster to dietary selection
Experimental populations ofD. melanogaster were subjected to long term dietary selection using sucrose and ethanol in two independent experiments. TheG6pd polymorphism exhibits a strong response to high sucrose selection whereas the6Pgd polymorphism exhlbits an equally strong response to ethanol selection.
D. R. Cavener
Defined morphological criteria allow reliable diagnosis of colorectal serrated polyps and predict polyp genetics.
Criteria for the diagnosis of serrated colorectal lesions (hyperplastic polyp, sessile serrated adenoma without or with dysplasia-which we called mixed polyp-and traditional serrated adenoma) for which consensus has been reached should be validated for applicability in daily practice in terms of inter-observer reproducibility and their association with clinical features and (epi)genetic events. A study set was created from a consecutive series of colorectal polyps (n?=?1,926) by selecting all sessile serrated adenomas, traditional serrated adenomas and mixed polyps. We added consecutive series of hyperplastic polyps, classical adenomas and normal mucosa samples for a total of 200 specimens. With this series, we conducted an inter-observer study, encompassing ten pathologists with gastrointestinal pathology experience from five European countries, in three rounds in which all cases were microscopically evaluated. An assessment of single morphological criteria was included, and these were correlated with clinical parameters and the mutation status of KRAS, BRAF and PIK3CA and the methylation status of MLH1. Gender, age and localisation were significantly associated with certain types of lesions. Kappa statistics revealed moderate to good inter-observer agreement for polyp classification (? = 0.56 to 0.63), but for single criteria, this varied considerably (? = 0.06 to 0.82). BRAF mutations were frequently found in hyperplastic polyps (86�%, 62/72) and sessile serrated adenomas (80�%, 41/51). KRAS mutations occurred more frequently in traditional serrated adenomas (78�%, 7/9) and less so in classical adenomas (20�%, 10/51). Single morphological criteria for sessile serrated adenomas showed significant correlation with BRAF mutation (all p???0.001), and those for classical adenomas or traditional serrated adenoma correlated significantly with KRAS mutation (all p?0.001). Therefore, single well-defined morphological criteria are predictive for genetic alterations in colorectal polyps. PMID:24728704
Rau, Tilman T; Agaimy, Abbas; Gehoff, Anastasia; Geppert, Carol; Jung, Klaus; Knobloch, Katharina; Langner, Cord; Lugli, Alessandro; Groenbus-Lurkin, Irene; Nagtegaal, Iris D; R�schoff, Josef; Saegert, Xavier; Sarbia, Mario; Schneider-Stock, Regine; Vieth, Michael; Zwarthoff, Ellen C; Hartmann, Arndt
Contribution of muscle biopsy and genetics to the diagnosis of chronic progressive external opthalmoplegia of mitochondrial origin.
Chronic progressive external opthalmoplegia (CPEO) is the most common phenotypic syndrome of the mitochondrial myopathies. Muscle biopsy, which provides important morphological clues for the diagnosis of mitochondrial disorders, is normal in approximately 25% of patients with CPEO, thus necessitating molecular genetic analysis for more accurate diagnosis. We aimed to study the utility of various histochemical stains in the diagnosis of CPEO on muscle biopsy and to correlate these results with genetic studies. Between May 2005 and November 2007 all 45 patients diagnosed with CPEO were included in the study (23 males; mean age at presentation, 35 years). Thirty-nine patients had CPEO only and six had CPEO plus; two had a positive family history but the remaining 39 patients had sporadic CPEO. Muscle biopsy samples were stained with hematoxylin and eosin, modified Gomori's trichrome stain, succinic dehydrogenase (SDH), cytochrome C oxidase (COX) and combined COX-SDH. Ragged red fibers were seen in 27 biopsies; seven showed characteristics of neurogenic atrophy only, and 11 were normal. The abnormal fibers were best identified on COX-SDH stain. A complete mitochondrial genome was amplified in muscle and blood samples of all patients. Mutations were found in transfer RNA, ribosomal RNA, ND, CYTB, COX I, II and III genes. Mitochondrial gene mutations were found in ten of the 11 patients with a normal muscle biopsy. The genetic mutations were classified according to their significance. The observed muscle biopsy findings were correlated with genetic mutations noted. Histological studies should be combined with genetic studies for the definitive diagnosis of CPEO syndrome. PMID:21277779
Sundaram, Challa; Meena, A K; Uppin, Megha S; Govindaraj, P; Vanniarajan, A; Thangaraj, K; Kaul, Subhash; Kekunnaya, Ramesh; Murthy, J M K
Cancer genetics-guided discovery of serum biomarker signatures for diagnosis and prognosis of prostate cancer
A key barrier to the realization of personalized medicine for cancer is the identification of biomarkers. Here we describe a two-stage strategy for the discovery of serum biomarker signatures corresponding to specific cancer-causing mutations and its application to prostate cancer (PCa) in the context of the commonly occurring phosphatase and tensin homolog (PTEN) tumor-suppressor gene inactivation. In the first stage of our approach, we identified 775 N-linked glycoproteins from sera and prostate tissue of wild-type and Pten-null mice. Using label-free quantitative proteomics, we showed that Pten inactivation leads to measurable perturbations in the murine prostate and serum glycoproteome. Following bioinformatic prioritization, in a second stage we applied targeted proteomics to detect and quantify 39 human ortholog candidate biomarkers in the sera of PCa patients and control individuals. The resulting proteomic profiles were analyzed by machine learning to build predictive regression models for tissue PTEN status and diagnosis and grading of PCa. Our approach suggests a general path to rational cancer biomarker discovery and initial validation guided by cancer genetics and based on the integration of experimental mouse models, proteomics-based technologies, and computational modeling.
Cima, Igor; Schiess, Ralph; Wild, Peter; Kaelin, Martin; Schuffler, Peter; Lange, Vinzenz; Picotti, Paola; Ossola, Reto; Templeton, Arnoud; Schubert, Olga; Fuchs, Thomas; Leippold, Thomas; Wyler, Stephen; Zehetner, Jens; Jochum, Wolfram; Buhmann, Joachim; Cerny, Thomas; Moch, Holger; Gillessen, Silke; Aebersold, Ruedi; Krek, Wilhelm
Genetic Diagnosis of Charcot-Marie-Tooth Disease in a Population by Next-Generation Sequencing
Charcot-Marie-Tooth (CMT) disease is the most prevalent inherited neuropathy. Today more than 40 CMT genes have been identified. Diagnosing heterogeneous diseases by conventional Sanger sequencing is time consuming and expensive. Thus, more efficient and less costly methods are needed in clinical diagnostics. We included a population based sample of 81?CMT families. Gene mutations had previously been identified in 22 families; the remaining 59 families were analysed by next-generation sequencing. Thirty-two CMT genes and 19 genes causing other inherited neuropathies were included in a custom panel. Variants were classified into five pathogenicity classes by genotype-phenotype correlations and bioinformatics tools. Gene mutations, classified certainly or likely pathogenic, were identified in 37 (46%) of the 81 families. Point mutations in known CMT genes were identified in 21 families (26%), whereas four families (5%) had point mutations in other neuropathy genes, ARHGEF10, POLG, SETX, and SOD1. Eleven families (14%) carried the PMP22 duplication and one family carried a MPZ duplication (1%). Most mutations were identified not only in known CMT genes but also in other neuropathy genes, emphasising that genetic analysis should not be restricted to CMT genes only. Next-generation sequencing is a cost-effective tool in diagnosis of CMT improving diagnostic precision and time efficiency.
H?yer, Helle; Braathen, Geir J.; Busk, ?yvind L.; Holla, ?ystein L.; Svendsen, Marit; Hilmarsen, Hilde T.; Strand, Linda; Skjelbred, Camilla F.; Russell, Michael B.
Application of SNP array for rapid prenatal diagnosis: implementation, genetic counselling and diagnostic flow
We report on the validation and implementation of the HumanCytoSNP-12 array (Illumina) (HCS) in prenatal diagnosis. In total, 64 samples were used to validate the Illumina platform (20 with a known (sub) microscopic chromosome abnormality, 5 with known maternal cell contamination (MCC) and 39 normal control samples). There were no false-positive or false-negative results. In addition to the diagnostic possibilities of arrayCGH, the HCS allows detection of regions of homozygosity (ROH), triploidy and helps recognising MCC. Moreover, in two cases of MCC, a deletion was correctly detected. Furthermore we found out that only about 50?ng of DNA is required, which allows a reporting time of only 3 days. We also present a prospective pilot study of 61 fetuses with ultrasound abnormalities and a normal karyotype tested with HCS. In 4 out of 61 (6.5%) fetuses, a clinically relevant abnormality was detected. We designed and present pre-test genetic counselling information on categories of possible test outcomes. On the basis of this information, about 90% of the parents chose to be informed about adverse health outcomes of their future child at infancy and childhood, and 55% also about outcomes at an adult stage. The latter issue regarding the right of the future child itself to decide whether or not to know this information needs to be addressed.
Srebniak, Malgorzata; Boter, Marjan; Oudesluijs, Gretel; Joosten, Marieke; Govaerts, Lutgarde; Van Opstal, Diane; Galjaard, Robert-Jan H
Different approaches for noninvasive prenatal diagnosis of genetic diseases based on PNA-mediated enriched PCR.
The aim of this work was to develop advanced and accessible protocols for noninvasive prenatal diagnosis of genetic diseases. We are evaluating different technologies for mutation detection, based on fluorescent probe hybridization of the amplified product and pyrosequencing, a technique that relies on the incorporation of nucleotides in a primer-directed polymerase extension reaction. In a previous investigation, we have already proven that these approaches are sufficiently sensitive to detect a few copies of a minority-mutated allele in the presence of an excess of wild-type DNA, In this work, in order to further enhance the sensitivity, we have employed a mutant enrichment amplification strategy based on the use of peptide nucleic acids (PNAs). These DNA analogues bind wild-type DNA, thus interfering with its amplification while still allowing the mutant DNA to become detectable. We have synthesized different PNAs, which are highly effective in clamping wild-type DNA in the beta-globin gene region, where four beta-thalassemia mutations are located (IVSI.110, CD39, IVSI.1, IVSI.6) plus HbS. The fluorescence microchip readout allows us to monitor the extent of wild-type allele inhibition, thus facilitating the assessment of the optimal PNA concentration. PMID:17108203
Galbiati, Silvia; Restagno, Gabriella; Foglieni, Barbara; Bonalumi, Sara; Travi, Maurizio; Piga, Antonio; Sbaiz, Luca; Chiari, Marcella; Damin, Francesco; Smid, Maddalena; Valsecchi, Luca; Pasi, Federica; Ferrari, Augusto; Ferrari, Maurizio; Cremonesi, Laura
Distorted Conversations: On and Offline Explorations of Genomic Art
This paper explores the metaphors of pre-implantation genetic diagnosis (PGD), or the genetic engineering of human embryos, through genomic art. Conversations about technologies like PGD typically center on issues of genetic determinism and autonomy. \\
Holly Longstaff
Combined Genetic Analysis of Sputum and Computed Tomography for Noninvasive Diagnosis of Non-Small-Cell Lung Cancer
Summary CT plays an important role in diagnosis of lung cancer, however has been limited by uncertain diagnostic rate for early stage of non�small-cell lung cancer (NSCLC), particularly central tumors. Genetic analysis of sputum has proven to be useful in diagnosis of NSCLC. We proposed to evaluate efficacy of combing CT and genetic analysis of sputum for noninvasive diagnosis of stage I NSCLC. Genomic copy changes of a panel of lung cancer-related genes, HYAL2, FHIT, p16, and SP-A were analyzed by a mini-chip in sputum from 33 patients with stage I NSCLC and 49 cancer-free controls. The genetic and CT diagnoses were compared with surgical-pathologic stage. CT had higher sensitivity (85%) in detection of lung cancer compared with the mini-chip (70%) (p<0.05), while there was no significant difference in specificity between the two tests (89 vs. 92%, p=0.09). Similarly, CT showed considerably higher sensitivity (93%) in identifying peripheral tumors than did the mini-chip (64%) (p<0.05), whereas there was no difference in specificity between them (98 vs. 96%, p=0.28). However, in detecting central tumors, CT had lower specificity (90%) compared with the mini-chip (98%) (P<0.05), although its sensitivity (79%) was higher than that of the mini-chip (73%) (P=0.05). Combining both tests offered higher sensitivity (91%) than did any single one (85%, 70%, all <0.05), while still keeping 92% sensitivity. In particular, this combined approach yielded higher sensitivity, specificity, and accuracy for diagnosing central cancers compared with CT alone (all p<0.05). The integration of the genetic assay with CT led to improvements in noninvasive diagnosis of stage I NSCLCs, especially central tumors.
Jiang, Feng; Todd, Nevins W.; Qiu, Qi; Liu, Zhenqiu; Katz, Ruth L.; Stass, Sanford A.
Combining fetal sonography with genetic and allele pathogenicity studies to secure a neonatal diagnosis of Bardet-Biedl syndrome
Bardet�Biedl syndrome (BBS) is a rare pediatric ciliopathy characterized by marked clinical variability and extensive genetic heterogeneity. Typical diagnosis of BBS is secured at a median of 9 years of age, and sometimes well into adolescence. Here, we report a patient in whom prenatal detection of increased nuchal fold, enlarged echogenic kidneys, and polydactyly prompted us to screen the most commonly mutated genes in BBS and the phenotypically and genetically overlapping ciliopathy, Meckel�Gruber syndrome (MKS). We identified the common Met390Arg mutation in BBS1 in compound heterozygosity with a novel intronic variant of unknown significance (VUS). Testing of mRNA harvested from primary foreskin fibroblasts obtained shortly after birth revealed the VUS to induce a cryptic splice site, which in turn led to a premature termination and mRNA degradation. To our knowledge, this is the earliest diagnosis of BBS in the absence of other affected individuals in the family, and exemplifies how combining clinical assessment with genetic and timely assays of variant pathogenicity can inform clinical diagnosis and assist with patient management in the prenatal and neonatal setting.
Ashkinadze, E.; Rosen, T.; Brooks, SS.; Katsanis, N.; Davis, EE.
A model reduction technique based on the PGD for elastic-viscoplastic computational analysis
In this paper a model reduction approach for elastic-viscoplastic evolution problems is considered. Enhancement of the PGD reduced model by a new iterative technique involving only elastic problems is investigated and allows to reduce CPU cost. The accuracy of the solution and convergence properties are tested on an academic example and a calculation time comparison with the commercial finite element code Abaqus is presented in the case of an industrial structure.
Relun, N.; N�ron, D.; Boucard, P. A.
Selection at 6-PGD locus in laboratory populations of Bactrocera oleae.
We have previously shown that laboratory populations of the olive fruitfly Bactrocera oleae come to equilibrium with allele frequencies at the 6-phosphogluconate dehydrogenase (6-PGD) locus markedly different from those of wild populations. In this study, we present new evidence from perturbation experiments in support of the notion that the locus is under selective pressure under laboratory conditions. Eleven populations were started with frequencies at the 6-PGD locus different from the laboratory equilibrium. Over 12 generations, the populations showed a return to the previous equilibrium, indicating a direct and powerful selection pressure on the naturally occurring allozymes of this locus. That is, a marked increase of the F allele followed by a compensatory decrease of allele I. Populations were set up to minimize the effects of associative overdominance, and we discuss the possible influence of this factor. Nucleotide sequence for the 6-PGD F and I alleles revealed two missense mutations at positions 501 and 730 leading to different amino acids among the two alleles. PMID:19061528
Cosmidis, Nikos; Goulielmos, George; Eliopoulos, Elias; Loukas, Michael
Are There Cultural Differences in Parental Interest in Early Diagnosis and Genetic Risk Assessment for Autism Spectrum Disorder?
Background: There are many societal and cultural differences between healthcare systems and the use of genetic testing in the US and France. These differences may affect the diagnostic process for autism spectrum disorder (ASD) in each country and influence parental opinions regarding the use of genetic screening tools for ASD. Methods: Using an internet-based tool, a survey of parents with at least one child with ASD was conducted. A total of 162 participants from the US completed an English version of the survey and 469 participants from France completed a French version of the survey. Respondents were mainly females (90%) and biological parents (94.3% in the US and 97.2% in France). Results: The mean age of ASD diagnosis reported was not significantly different between France (57.5?�?38.4?months) and the US (56.5?�?52.7?months) (p?=?0.82) despite significant difference in the average age at which a difference in development was first suspected [29.7?months (�28.4) vs. 21.4?months (�18.1), respectively, p?=?7?�?10?4]. Only 27.8% of US participants indicated that their child diagnosed with ASD had undergone diagnostic genetic testing, whereas 61.7% of the French participants indicated this was the case (p?=?2.7?�?10?12). In both countries, the majority of respondents (69.3% and 80% from France and the US, respectively) indicated high interest in the use of a genetic screening test for autism. Conclusion: Parents from France and the US report a persistent delay between the initial suspicion of a difference in development and the diagnosis of ASD. Significantly fewer US participants underwent genetic testing although this result should be regarded as exploratory given the limitations. The significance of these between country differences will be discussed.
Amiet, Claire; Couchon, Elizabeth; Carr, Kelly; Carayol, Jerome; Cohen, David
The genetic screening of preimplantation embryos by comparative genomic hybridisation.
Comparative genomic hybridization (CGH) is an indirect DNA-based test which allows for the accurate analysis of aneuploidy involving any of the 24 types of chromosomes present (22 autosomes and the X and Y sex chromosomes). Traditionally, embryos have been screened using fluorescence in situ hybridization (FISH)--a technique that was limited in the number of chromosomes able to be identified in any one sample. Early CGH reports on aneuploidy in preimplantation embryos showed that any of the 24 chromosomes could be involved and so FISH methods were going to be ineffective in screening out abnormal embryos. Our results from routine clinical application of array CGH in preimplantation genetic diagnosis (PGD) patients confirm previous reports on patterns of chromosomal contribution to aneuploidy. The pregnancy outcomes following embryo transfer also indicate that despite the requirement to freeze embryos, rates are encouraging, and successful ongoing pregnancies can be achieved. PMID:22200879
Traversa, Maria V; Marshall, James; McArthur, Steven; Leigh, Don
Assisted procreation and its relationship to genetics and eugenics.
The article below is intended to reflect on whether or not a eugenic tendency constitutes an intrinsic element of human fertilization in vitro. The author outlines ideas and circumstances which characterized the foundation and propagation of eugenics between the eighteenth and nineteenth centuries. A brief discussion follows on some of the standard procedures of in vitro fertilization, and in particular, those which manifest a trace or hint of eugenics--heterologous fertilization and sperm banking, preimplantation genetic diagnosis (PGD) and embryo selection--practices which, nonetheless, are used on a large scale and shed light on both the essence of procreative medicine and on the current cultural environment. The objective of the article is to explore whether it is possible to eliminate the eugenic connotations without foregoing the benefits of technical and scientific progress. PMID:19580100
Ricci, Mariella Lombardi
An automatic scanning method for high throughput microscopic system to facilitate medical genetic diagnosis: an initial study
The purpose of this paper is to report a new automatic scanning scheme for high throughput microscopic systems aiming to facilitate disease diagnosis in genetic laboratories. To minimize the impact of the random vibration and mechanical drifting of the scanning stage in microscopic image acquisition, auto-focusing operations are usually applied repeatedly during the scanning process. Such methods ensure the acquisition of well focused images for clinical diagnosis, but are time consuming. The technique investigated in this preliminary study applies the auto-focusing operations at a limited number of locations on the slide. For the rest of the imaging field, the focusing position is quickly adjusted through linear interpolation. In this initial validation study, blood pathological slides containing both metaphase and interphase cells are scanned. For a selected area of 6.9mm�6.9mm, a number of 2�2, 3�2, 3�3, and 4�4 positions are evenly sampled for auto-focusing operations. Respectively, 25, 29, 40, and 41 clinically meaningful cells are identified for each sampling scheme. For the specific case investigated, the results demonstrate that the 4 position auto-focusing scheme could obtain the adequate number of clinically meaningful cells for the diagnosis. The schemes with more auto-focusing operations provide an option for high reliability diagnosis when clinically necessary. More comprehensive research is planned, and that may lead to optimal design of trade-off for developing the scanning scheme of the high throughput microscopic systems.
Qiu, Yuchen; Chen, Xiaodong; Li, Zheng; Li, Yuhua; Chen, Wei R.; Zheng, Bin; Li, Shibo; Liu, Hong
Genetic Diagnosis in Consanguineous Families With Kidney Disease by Homozygosity Mapping Coupled With Whole-Exome Sequencing
Background Accurate diagnosis of the primary cause of an individual�s kidney disease can be essential for proper management. Some kidney diseases have overlapping histopathological features despite being caused by defects in different genes. In this report we describe two consanguineous Saudi Arabian families in which individuals presented with kidney failure and mixed clinical and histological features initially thought consistent with focal segmental glomerulosclerosis. Study Design Case series. Setting and participants We studied members of two apparently unrelated families from Saudi Arabia with kidney disease. Measurements Whole-genome single-nucleotide polymorphism analysis followed by targeted isolation and sequencing of exons using genomic DNA samples from affected members of these families, followed by additional focused genotyping and sequence analysis. Results The two apparently unrelated families shared a region of homozygosity on chromosome 2q13. Exome sequence from the affected individuals lacked any sequence reads from the NPHP1 gene, which is located within this homozygous region. Additional PCR based genotyping confirmed that affected individuals had NPHP1 deletions, rather than defects in a known FSGS-associated gene. Limitations The methods used here may not result in a clear genetic diagnosis in many cases of apparent familial kidney disease. Conclusions This analysis demonstrates the power of new high-throughput genotyping and sequencing technologies to aid in the rapid genetic diagnosis of individuals with an inherited form of kidney disease. We believe it is likely that such tools may become useful clinical genetic tools and alter the manner in which diagnoses are made in nephrology.
Al-Romaih, Khaldoun I.; Genovese, Giulio; Al-Mojalli, Hamad; Al-Othman, Saleh; Al-Manea, Hadeel; Al-Suleiman, Mohammed; Al-Jondubi, Mohammed; Atallah, Nourah; Al-Rodhyan, Maha; Weins, Astrid; Pollak, Martin R.; Adra, Chaker N.
[The progress and strategy of molecular diagnosis for human genetic diseases].
Recently, the human genome project has progressed and the responsible genes for many diseases have been discovered. Molecular diagnosis based on gene analysis techniques has developed. In this paper, the methods in molecular diagnosis were explained, taking as examples of several pediatric neurological diseases such as GM1- gangliosidosis, fragile X syndrome and congenital myotonic dystrophy. Next, we stressed the importance of the study on the gene function in related to the gene mutation. Finally the strategy to establish the molecular diagnosis of polygenic diseases, such as mental retardation and autism, was considered. PMID:9545776
Nanba, E
How can genetics and epigenetics help the nephrologist improve the diagnosis and treatment of chronic kidney disease patients?
Discovery of novel improved tools for diagnosis, prevention and therapy of chronic kidney disease (CKD) is an important task for the nephrology community and it is likely that scientific breakthroughs, to a large extent, will be based on genomics. The rapid growth of the number of genome-wide association studies, major advances in DNA sequencing and omics profiling, and accelerating biomedical research efforts in this area have greatly expanded the knowledge base needed for applied genomics. However, translating and implementing genotype-phenotype data into gene-based medicine in CKD populations is still in an early phase and will require continuous research efforts with integrated approaches and intensified investigations that focus on the biological pathways, which causatively link a genetic variant with the disease phenotype. In this article, we review some current strategies to unravel these translational gaps as well as prospects for the implementation of genetic and epigenetic methods into novel clinical practice. PMID:24569498
Witasp, Anna; Ekstr�m, Tomas J; Schalling, Martin; Lindholm, Bengt; Stenvinkel, Peter; Nordfors, Louise
Hematopoietic-Prostaglandin D2 synthase through PGD2 production is involved in the adult ovarian physiology
Background The prostaglandin D2 (PGD2) pathway is involved in numerous biological processes and while it has been identified as a partner of the embryonic sex determining male cascade, the roles it plays in ovarian function remain largely unknown. PGD2 is secreted by two prostaglandin D synthases (Pgds); the male-specific lipocalin (L)-Pgds and the hematopoietic (H)-Pgds. Methods To study the expression of the Pgds in the adult ovary, in situ hybridization were performed. Then, to evaluate the role of H-Pgds produced PGD2 in the ovarian physiology, adult female mice were treated with HQL-79, a specific inhibitor of H-Pgds enzymatic activity. The effects on expression of the gonadotrophin receptors FshR and LhR, steroidogenic genes Cyp11A1, StAR and on circulating progesterone and estradiol, were observed. Results We report the localization of H-Pgds mRNA in the granulosa cells from the primary to pre-ovulatory follicles. We provide evidence of the role of H-Pgds-produced PGD2 signaling in the FSH signaling through increased FshR and LhR receptor expression. This leads to the activation of steroidogenic Cyp11A1 and StAR gene expression leading to progesterone secretion, independently on other prostanoid-synthetizing mechanisms. We also identify a role whereby H-Pgds-produced PGD2 is involved in the regulation of follicular growth through inhibition of granulosa cell proliferation in the growing follicles. Conclusions Together, these results show PGD2 signaling to interfere with FSH action within granulosa cells, thus identifying an important and unappreciated role for PGD2 signaling in modulating the balance of proliferation, differentiation and steroidogenic activity of granulosa cells.
Access to medical-assisted reproduction and pgd in Italian law: a deadly blow to an illiberal statute? commentary to the European Court on Human Rights's decision Costa and Pavan v Italy (ECtHR, 28 August 2012, App. 54270/2010).
This article provides an account of the European Court on Human Rights' Second Section decision in the case Costa and Pavan v Italy. The judgment found that the Italian Statute on Assisted Reproduction (Law 40/2004), and particularly its prohibition to use in vitro fertilisation and pre-implantation genetic diagnosis (PGD) to prevent the birth of children affected by genetically transmissible conditions, breached Article 8 of the European Convention on Human Rights (ECHR). In fact, the statute in question permits only infertile people to access medically assisted reproduction techniques and forbids PGD and embryo selection. The Court regarded that the rationale of these prohibitions-identified by the Italian Government with the need to prevent eugenic practices as well as to protect the health of the unborn and of the woman-was at odds with the fact that Italian law allows pre-natal screening and therapeutic abortions in case foetal abnormalities are diagnosed. In order to clarify the decision's significance, the paper goes on to analyse the rationale of Law 40/2004 in the Italian legal and political context. Emphasis is placed on the fact that this statute is extremely controversial at domestic level, because many of its provisions-including those considered by the Strasbourg Court-are inherently contradictory and contrast with the settled constitutional principles on abortion, as many domestic authorities highlighted. In this context, should the commented decision be confirmed by the Grand Chamber, it may provide a basis to bring consistency back to the Italian regulation of assisted reproduction. Finally, the paper considers the appeal lodged by the Italian Government to the Grand Chamber, and in particular the contention that the European Court had failed to respect Italy's margin of appreciation. In this regard, it is argued that, under Law 40/2004, individuals face illogical and discriminatory restrictions to their right to private and family life and that therefore, even if an outright violation of Article 8 ECHR could not be found, there appears to be at least a breach of Article 8 in conjunction with Article 14 ECHR. PMID:23552505
Biondi, Stefano
Analysis of five polymorphic DNA markers for indirect genetic diagnosis of haemophilia A in the Brazilian population.
Hemophilia A is an X-linked, inherited, bleeding disorder caused by the partial or total inactivity of the coagulation factor VIII (FVIII). Due to difficulties in the direct recognition of the disease-associated mutation in the F8 gene, indirect diagnosis using polymorphic markers located inside or close to the gene is used as an alternative for determining the segregation of the mutant gene within families and thus for detecting carrier individuals and/or assisting in prenatal diagnosis. This study characterizes the allelic and haplotype frequencies, genetic diversity, population differentiation and linkage disequilibrium of five microsatellites (F8Int1, F8Int13, F8Int22, F8Int25.3 and IKBKG) in samples of healthy individuals from S�o Paulo, Rio Grande do Sul and Pernambuco and of patients from S�o Paulo with haemophilia A to determine the degree of informativeness of these microsatellites for diagnostic purposes. The interpopulational diversity parameters highlight the differences among the analyzed population samples. Regional differences in allelic frequencies must be taken into account when conducting indirect diagnosis of haemophilia A. With the exception of IKBKG, all of the microsatellites presented high heterozygosity levels. Using the markers described, diagnosis was possible in 10 of 11 families. The F8Int22, F8Int1, F8Int13, F8Int25.3 and IKBKG microsatellites were informative in seven, six, five and two of the cases, respectively, demonstrating the effectiveness of using these microsatellites in prenatal diagnosis and in carrier identification in the Brazilian population. PMID:21649803
Massaro, J D; Wiezel, C E V; Muniz, Y C N; Rego, E M; de Oliveira, L C O; Mendes-Junior, C T; Sim�es, A L
Genetic testing: predictive value of genotyping for diagnosis and management of disease
This article describes predictive, preventive value of genetic tests and the implication of the use of testing for personalized\\u000a treatment. This year marks the 10th anniversity of publishing of the sequence of the human genome. One important area of application\\u000a of this mega project is a development of genetic tests for mutation detection in single gene disorders that has impact
Meral �zg��
KRT9 gene mutation as a reliable indicator in the prenatal molecular diagnosis of epidermolytic palmoplantar keratoderma.
Epidermolytic palmoplantar keratoderma (EPPK) is the most frequent form of such keratodermas. It is inherited in an autosomal dominant pattern and is clinically characterized by diffuse yellowish thickening of the skin on the palms and soles with erythematous borders during the first weeks or months after birth. EPPK is generally caused by mutations of the KRT9 gene. More than 26 KRT9 gene mutations responsible for EPPK have been described (Human Intermediate Filament Database, www.interfil.org), and many of these variants are located within the highly-conserved coil 1A region of the ?-helical rod domain of keratin 9. Unfortunately, there is no satisfactory treatment for EPPK. Thus, prenatal molecular diagnosis or pre-pregnancy diagnosis is crucial and benefits those affected who seek healthy descendants. In the present study, we performed amniotic fluid-DNA-based prenatal testing for three at-risk pregnant EPPK women from three unrelated southern Chinese families who carried the KRT9 missense mutations p.Arg163Trp and p.Arg163Gln, and successfully helped two families to bear normal daughters. We suggest that before the successful application of preimplantation genetic diagnosis (PGD), and noninvasive prenatal diagnosis of EPPK that analyzes fetal cells or cell-free DNA in maternal blood, prenatal genetic diagnosis by amniocentesis or chorionic villus sampling (CVS) offers a quite acceptable option for EPPK couples-at-risk to avoid the birth of affected offspring, especially in low- and middle-income countries. PMID:24862219
Ke, Hai-Ping; Jiang, Hu-Ling; Lv, Ya-Su; Huang, Yi-Zhou; Liu, Rong-Rong; Chen, Xiao-Ling; Du, Zhen-Fang; Luo, Yu-Qin; Xu, Chen-Ming; Fan, Qi-Hui; Zhang, Xian-Ning
The clinical application of non-genetic biomarkers for differential diagnosis of monogenic diabetes
Diabetes mellitus is not a single disorder but rather a heterogeneous group of diseases that differ in respect to pathogenesis, the clinical picture and the response to dietary and pharmacological treatments. Thus, the differential diagnosis of various types and forms of diabetes is of great practical importance. This is particularly true for monogenic disease forms where some spectacular applications of
Katharine R. Owen; Jan Skupien; Maciej T. Malecki
When a person at risk of having a child with a genetic illness or disease wishes to have an unaffected child, this can involve difficult choices. If the pregnancy is established by sexual intercourse, the fetus can be tested early in pregnancy, and if affected a decision can be made to abort in the hope that a future pregnancy with
C Cameron; R Williamson
Prenatal Diagnosis of Thanatophoric Dysplasia by 3-D Helical Computed Tomography and Genetic Analysis
Objective: We report the first case of thanatophoric dysplasia (TD) successfully diagnosed in utero by a combination of 2-D ultrasound, computed tomography (CT) 3-D imaging and genetic analysis at 26 weeks� gestation. Methods: Prenatal sonographic examinations performed at 23 weeks� gestation revealed micromelic shortening of the limbs, reduced thoracic cavity and a presence of cloverleaf skull deformity. Based on these
Seiji Tsutsumi; Hideaki Sawai; Gen Nishimura; Kiyoshi Hayasaka; Hirohisa Kurachi
Review The long QT syndrome: Therapeutic implications of a genetic diagnosisB
The congenital long QT syndrome (LQTS) is a hereditary disorder characterized by a prolonged QT interval and a polymorphic ventricular tachycardia, known as Torsade de Pointes (TdP), leading to severe cardiac events such as syncope and\\/or sudden cardiac death. Molecular genetic studies have revealed a total of eight forms of congenital LQTS caused by mutations in genes of the potassium,
Wataru Shimizu
Diagnosis of Alexander disease in a Japanese patient by molecular genetic analysis
Alexander disease is a leukodystrophy that is neuropathologically characterized by the presence of numerous Rosenthal fibers\\u000a in astrocytes. Recently, mutations in the gene encoding glial fibrillary acidic protein (GFAP) were identified in patients\\u000a with Alexander disease. We sequenced the GFAP gene of a Japanese girl who presented with typical symptoms of Alexander disease but in whom the diagnosis was not
Naohide Shiroma; Naomi Kanazawa; Mina Izumi; Kenji Sugai; Michio Fukumizu; Masayuki Sasaki; Shigeru Hanaoka; Makiko Kaga; Seiichi Tsujino
Ichthyosis bullosa of Siemens: its correct diagnosis facilitated by molecular genetic testing.
Ichthyosis bullosa of Siemens (IBS, MIM 146800) is a unique congenital ichthyosis characterized by mild epidermal hyperkeratosis over flexural areas, blister formation and the development of superficially denuded areas of hyperkeratotic skin. It is clinically difficult to distinguish severe IBS from mild bullous congenital ichthyosiform erythroderma (BCIE, MIM 113800). In the current literature, 19 IBS families with keratin 2e (K2e) mutations have been reported, despite only five IBS families having been reported before the first identification of K2e mutation in 1994. We studied four patients from three Japanese IBS families. They had previously been misdiagnosed as having BCIE before the correct diagnosis was made after mutation detection. To detect the pathogenic mutations, we performed direct sequencing of the entire coding regions of KRT2E encoding K2e in the patients and healthy family members. K2e mutations, a 1469T-->C transition (L490P) and a 1477G-->A transition (E493K) within the conserved 2B helix termination motif of the rod domain were detected in the families and the definite diagnosis of IBS was made in the four cases. The present results indicate that IBS is not such a rare entity as was previously thought, and accurate diagnosis is now available by mutation analysis. PMID:15949009
Akiyama, M; Tsuji-Abe, Y; Yanagihara, M; Nakajima, K; Kodama, H; Yaosaka, M; Abe, M; Sawamura, D; Shimizu, H
... Inheritance; Heterozygous; Inheritance patterns; Heredity and disease; Heritable; Genetic markers ... The chromosomes are made up of strands of genetic information called DNA. Genes are sections of DNA. ...
Molecular Marker Studies in Riverine Buffaloes, for Characterization and Diagnosis of Genetic Defects
The buffalo is probably the last livestock species to have been domesticated, with many genetic, physiological and behavioural\\u000a traits not yet well understood. Molecular markers have been used for characterizing animals and breeds, diagnosing diseases\\u000a and identifying anatomical and physiological anomalies. RFLP studies showed low heterozygosity, but genomic and oligonucleotide\\u000a probes showed species-specific bands useful for identification of carcass or
B. R. Yadav
Pituitary Tumors in Childhood: an update in their diagnosis, treatment and molecular genetics
Pituitary tumors are rare in childhood and adolescence, with a reported prevalence of up to 1 per million children. Only 2 - 6% of surgically treated pituitary tumors occur in children. Although pituitary tumors in children are almost never malignant and hormonal secretion is rare, these tumors may result in significant morbidity. Tumors within the pituitary fossa are of two types mainly, craniopharyngiomas and adenomas; craniopharyngiomas cause symptoms by compressing normal pituitary, causing hormonal deficiencies and producing mass effects on surrounding tissues and the brain; adenomas produce a variety of hormonal conditions such as hyperprolactinemia, Cushing disease and acromegaly or gigantism. Little is known about the genetic causes of sporadic lesions, which comprise the majority of pituitary tumors, but in children, more frequently than in adults, pituitary tumors may be a manifestation of genetic conditions such as multiple endocrine neoplasia type 1 (MEN 1), Carney complex, familial isolated pituitary adenoma (FIPA), and McCune-Albright syndrome. The study of pituitary tumorigenesis in the context of these genetic syndromes has advanced our knowledge of the molecular basis of pituitary tumors and may lead to new therapeutic developments.
Keil, Margaret F.; Stratakis, Constantine A.
Purification and characterization of 6-phosphogluconate dehydrogenase (6-PGD) from grass carp (Ctenopharyngodon idella) hepatopancreas.
6-Phosphogluconate dehydrogenase (6-PGD, E.C.: 22.214.171.124) was purified and characterized from the hepatopancreas of grass carp (Ctenopharyngodon idella) for the first time. Grass carp represents the second largest aquaculture industry in the world after silver carp, constituting 14.7% of the world aquaculture production, with an average annual increase of 14% in China, mainly as a source of food. The purification procedure involved a single 2', 5'-ADP-Sepharose 4B affinity chromatographic step by using different elution buffers. The enzyme was purified 309-fold with a specific activity of 5.259 U/mg protein and yield of 68%. The purity and subunit molecular weights of the 6-PGD were checked on SDS-PAGE and purified enzyme showed a single band on the gel. The subunit molecular mass was 57 kDa, with an optimum pH, temperature and ionic strength at 7.96, 50 degrees C and 100 mM Tris-HCl, respectively. The Km values of 6-PGA and NADP+ were 0.019 and 0.0052 mM, respectively, while Vm of 6-PGA and NADP+ was 0.69 U/ml. Dissociation constants (Ki) for 6-PGA and NADP+ were 2.05 and 0.12 mM, respectively. NADPH inhibited the enzyme in a competitive manner and its Ki value was 0.032 mM. The Cu2+, Zn2+, Cd2+ and Al3+ showed inhibitory effects on the enzyme with IC50 values of 0.293, 0.099, 0.045 and 1.526 mM, respectively. All tested metals inhibited the enzyme in a competitive manner, indicating that these metals might be toxic even at low concentrations for the 6-PGD. As the fish is one of valuable foodstuff of animal sources for human consumption, under certain environmental conditions, metal ions accumulated in fish up to a lethal concentration may be harmful for human health. Therefore, it is impending to reduce the concentration of metal ions in contaminated lakes and rivers for fishery and also for human health. PMID:24772981
Sun, Lin-Dan; Luo, Zhi; Hu, Wei; Zhuo, Mei-Qin; Zheng, Jia-Lang; Chen, Qi-Liang; Liang, Xu-Fang; Xiong, Bang-Xi
PGD and separated space variables representation for linear elasticity in 3D representation of plate domains
In this paper, we focus on the simulation of linear elastic behaviour of plates using a 3D approach which numerical cost only scales like a 2D one. In the case of plates, the kinematic hypothesis introduced in plate theories to go from 3D to 2D is usually unsatisfactory where one cannot rely on St Venant's principle (usually close to the plate edges). We propose to apply the PGD (Proper Generalized Decomposition) method [1] to the simulation of the linear elastic behavior of plates. This method allows us to separately search for the in-plane and the out-of plane contributions to the 3D solution, yielding significant savings in computational cost. The method is validated on a simple case and its full potential is then presented for the simulation of the behavior of laminated composite plates.
Bognet, B.; Leygue, A.; Chinesta, F.; Poitou, A.
Linkage disequilibrium pattern and age-at-diagnosis are critical for replicating genetic associations across ethnic groups in leprosy.
One of the persistent challenges of genetic association studies is the replication of genetic marker-disease associations across ethnic groups. Here, we conducted high-density association mapping of PARK2/PACRG SNPs with leprosy and identified 69 SNPs significantly associated with leprosy in 198 single-case Vietnamese leprosy families. A total of 56 associated SNPs localized to the overlapping promoter regions of PARK2/PACRG. For this region, multivariate analysis identified four SNPs belonging to two major SNP bins (rs1333955, rs7744433) and two single SNP bins (rs2023004, rs6936895) that capture the combined statistical evidence (P = 1.1 � 10(-5)) for association among Vietnamese patients. Next, we enrolled a case-control sample of 364 leprosy cases and 370 controls from Northern India. We genotyped all subjects for 149 SNPs that capture >80 % of the genetic variation in the Vietnamese sample and found 24 SNPs significantly associated with leprosy. Multivariate analysis identified three SNPs (rs1333955, rs9356058 and rs2023004) that capture the association with leprosy (P < 10(-8)). Hence, two SNPs (rs1333955 and rs2023004) were replicated by multivariate analysis between both ethnic groups. Marked differences in the linkage disequilibrium pattern explained some of the differences in univariate analysis between the two ethnic groups. In addition, the strength of association for two promoter region SNP bins was significantly stronger among young leprosy patients in the Vietnamese sample. The same trend was observed in the Indian sample, but due to the higher age-at-diagnosis of the patients the age effect was less pronounced. PMID:23052943
Alter, Andrea; Fava, Vinicius Medeiros; Huong, Nguyen Thu; Singh, Meenakshi; Orlova, Marianna; Van Thuc, Nguyen; Katoch, Kiran; Thai, Vu Hong; Ba, Nguyen Ngoc; Abel, Laurent; Mehra, Narinder; Alca�s, Alexandre; Schurr, Erwin
The Effect of Ddt on the Polymorphism at the G6pd and Pgd Loci in DROSOPHILA MELANOGASTER
For the degradation of DDT and other chlorohydrocarbon insecticides energy in the form of NADPH is needed which for the greater part is supplied by the pentose phosphate shunt. Therefore the influence of DDT on the polymorphism at the G6pd and Pgd loci in Drosophila melanogaster was investigated by studying its effect on egg to adult survival and adult survival. The results show the existence of significant differences in fitness between the different genotypes of the two loci for both components. It is found that the effect of DDT supplementation differs significantly from the effect of sodium octanoate addition. DDT treatment also increases the activity of the pentose phosphate shunt as measured by the activity of G6PD and 6PGD. In larvae a 50% increase in activity is found and in adults a 100% increase. As there is little doubt that the activities of G6PD and 6PGD are somehow correlated with the fitness of flies, the data are discussed in relation to the in vitro and in vivo differences in activity between the different allozymes of both G6PD and 6PGD.
Bijlsma, R.; Kerver, J. W. M.
Polymorphism at the G6pd and 6Pgd loci in Drosophila melanogaster . III. Developmental and biochemical aspects
The electrophoretic variants of G6PD and 6PGD isolated from the Bogota Drosophila melanogaster population were characterized developmentally and biochemically. Changes in in vitro enzyme activity during development were comparable to those found for other dehydrogenases: an increase in the larval and adult stage and a decrease in the pupal stage. During the whole life cycle the �S� enzyme of both
R. Bijlsma; C. van der Meulen-Bruijns
The effect of DDT on the polymorphism at the G6pd and Pgd loci in Drosophila melanogaster.
For the degradation of DDT and other chlorohydrocarbon insecticides energy in the form of NADPH is needed which for the greater part is supplied by the pentose phosphate shunt. Therefore the influence of DDT on the polymorphism at the G6pd and Pgd loci in Drosophila melanogaster was investigated by studying its effect on egg to adult survival and adult survival. The results show the existence of significant differences in fitness between the different genotypes of the two loci for both components. It is found that the effect of DDT supplementation differs significantly from the effect of sodium octanoate addition. DDT treatment also increases the activity of the pentose phosphate shunt as measured by the activity of G6PD and 6PGD. In larvae a 50% increase in activity is found and in adults a 100% increase. As there is little doubt that the activities of G6PD and 6PGD are somehow correlated with the fitness of flies, the data are discussed in relation to the in vitro and in vivo differences in activity between the different allozymes of both G6PD and 6PGD. PMID:6404694
Bijlsma, R; Kerver, J W
Diagnosis of Fanconi Anemia: Mutation Analysis by Multiplex Ligation-Dependent Probe Amplification and PCR-Based Sanger Sequencing
Fanconi anemia (FA) is a rare inherited disease characterized by developmental defects, short stature, bone marrow failure, and a high risk of malignancies. FA is heterogeneous: 15 genetic subtypes have been distinguished so far. A clinical diagnosis of FA needs to be confirmed by testing cells for sensitivity to cross-linking agents in a chromosomal breakage test. As a second step, DNA testing can be employed to elucidate the genetic subtype of the patient and to identify the familial mutations. This knowledge allows preimplantation genetic diagnosis (PGD) and enables prenatal DNA testing in future pregnancies. Although simultaneous testing of all FA genes by next generation sequencing will be possible in the near future, this technique will not be available immediately for all laboratories. In addition, in populations with strong founder mutations, a limited test using Sanger sequencing and MLPA will be a cost-effective alternative. We describe a strategy and optimized conditions for the screening of FANCA, FANCB, FANCC, FANCE, FANCF, and FANCG and present the results obtained in a cohort of 54 patients referred to our diagnostic service since 2008. In addition, the follow up with respect to genetic counseling and carrier screening in the families is discussed.
Gille, Johan J. P.; Floor, Karijn; Kerkhoven, Lianne; Ameziane, Najim; Joenje, Hans; de Winter, Johan P.
A homozygous double mutation in SMN1: a complicated genetic diagnosis of SMA
Spinal muscular atrophy (SMA), the most common autosomal recessive cause of infant death, is typically diagnosed by determination of SMN1 copy number. Approximately 3�5% of patients with SMA retain at least one copy of the SMN1 gene carrying pathogenic insertions, deletions, or point mutations. We report a patient with SMA who is homozygous for two mutations carried in cis: an 8 bp duplication (c.48_55dupGGATTCCG; p.Val19fs*24) and a point mutation (c.662C>T; p.Pro221Leu). The consanguineous parents carry the same two mutations within one SMN1 gene copy. We demonstrate that a more accurate diagnosis of the disease is obtained through a novel diagnostic assay and development of a capillary electrophoresis method to determine the copy number of their mutant alleles. This illustrates the complexity of SMN mutations and suggests additional testing (gene sequencing) may be appropriate when based on family lines.
Kirwin, Susan M; Vinette, Kathy M B; Gonzalez, Iris L; Abdulwahed, Hind Al; Al-Sannaa, Nouriya; Funanage, Vicky L
Telethon Network of Genetic Biobanks: a key service for diagnosis and research on rare diseases
Several examples have always illustrated how access to large numbers of biospecimens and associated data plays a pivotal role in the identification of disease genes and the development of pharmaceuticals. Hence, allowing researchers to access to significant numbers of quality samples and data, genetic biobanks are a powerful tool in basic, translational and clinical research into rare diseases. Recently demand for well-annotated and properly-preserved specimens is growing at a high rate, and is expected to grow for years to come. The best effective solution to this issue is to enhance the potentialities of well-managed biobanks by building a network. Here we report a 5-year experience of the Telethon Network of Genetic Biobanks (TNGB), a non-profit association of Italian repositories created in 2008 to form a virtually unique catalogue of biospecimens and associated data, which presently lists more than 750 rare genetic defects. The process of TNGB harmonisation has been mainly achieved through the adoption of a unique, centrally coordinated, IT infrastructure, which has enabled (i) standardisation of all the TNGB procedures and activities; (ii) creation of an updated TNGB online catalogue, based on minimal data set and controlled terminologies; (iii) sample access policy managed via a shared request control panel at web portal. TNGB has been engaged in disseminating information on its services into both scientific/biomedical - national and international - contexts, as well as associations of patients and families. Indeed, during the last 5-years national and international scientists extensively used the TNGB with different purposes resulting in more than 250 scientific publications. In addition, since its inception the TNGB is an associated member of the Biobanking and Biomolecular Resources Research Infrastructure and recently joined the EuroBioBank network. Moreover, the involvement of patients and families, leading to the formalization of various agreements between TNGB and Patients� Associations, has demonstrated how promoting Biobank services can be instrumental in gaining a critical mass of samples essential for research, as well as, raising awareness, trust and interest of the general public in Biobanks. This article focuses on some fundamental aspects of networking and demonstrates how the translational research benefits from a sustained infrastructure.
Saudi Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Genetics of pulmonary hypertension
Pulmonary hypertension (PH) is a phenotype characterized by functional and structural changes in the pulmonary vasculature, leading to increased vascular resistance.[12] The World Health Organization has classified PH into five different types: arterial, venous, hypoxic, thromboembolic or miscellaneous; details are available in the main guidelines. Group I of this classification, designated as pulmonary arterial hypertension (PAH), will remain the main focus here. The pathophysiology involves signaling, endothelial dysfunction, activation of fibroblasts and smooth muscle cells, interaction between cells within the vascular wall, and the circulating cells; as a consequence plexiform lesions are formed, which is common to both idiopathic and heritable PAH but are also seen in other forms of PAH.[234] As the pathology of PAH in the lung is well known, this article focuses on the genetic aspects associated with the disease and is a gist of several available articles in literature.
Pasha, Qadar
Exome sequencing improves genetic diagnosis of structural fetal abnormalities revealed by ultrasound.
The genetic etiology of non-aneuploid fetal structural abnormalities is typically investigated by karyotyping and array-based detection of microscopically detectable rearrangements, and submicroscopic copy-number variants (CNVs), which collectively yield a pathogenic finding in up to 10% of cases. We propose that exome sequencing may substantially increase the identification of underlying etiologies. We performed exome sequencing on a cohort of 30 non-aneuploid fetuses and neonates (along with their parents) with diverse structural abnormalities first identified by prenatal ultrasound. We identified candidate pathogenic variants with a range of inheritance models, and evaluated these in the context of detailed phenotypic information. We identified 35 de novo single-nucleotide variants (SNVs), small indels, deletions or duplications, of which three (accounting for 10% of the cohort) are highly likely to be causative. These are de novo missense variants in FGFR3 and COL2A1, and a de novo 16.8 kb deletion that includes most of OFD1. In five further cases (17%) we identified de novo or inherited recessive or X-linked variants in plausible candidate genes, which require additional validation to determine pathogenicity. Our diagnostic yield of 10% is comparable to, and supplementary to, the diagnostic yield of existing microarray testing for large chromosomal rearrangements and targeted CNV detection. The de novo nature of these events could enable couples to be counseled as to their low recurrence risk. This study outlines the way for a substantial improvement in the diagnostic yield of prenatal genetic abnormalities through the application of next-generation sequencing. PMID:24476948
Carss, Keren J; Hillman, Sarah C; Parthiban, Vijaya; McMullan, Dominic J; Maher, Eamonn R; Kilby, Mark D; Hurles, Matthew E
Exome sequencing improves genetic diagnosis of structural fetal abnormalities revealed by ultrasound
The genetic etiology of non-aneuploid fetal structural abnormalities is typically investigated by karyotyping and array-based detection of microscopically detectable rearrangements, and submicroscopic copy-number variants (CNVs), which collectively yield a pathogenic finding in up to 10% of cases. We propose that exome sequencing may substantially increase the identification of underlying etiologies. We performed exome sequencing on a cohort of 30 non-aneuploid fetuses and neonates (along with their parents) with diverse structural abnormalities first identified by prenatal ultrasound. We identified candidate pathogenic variants with a range of inheritance models, and evaluated these in the context of detailed phenotypic information. We identified 35 de novo single-nucleotide variants (SNVs), small indels, deletions or duplications, of which three (accounting for 10% of the cohort) are highly likely to be causative. These are de novo missense variants in FGFR3 and COL2A1, and a de novo 16.8 kb deletion that includes most of OFD1. In five further cases (17%) we identified de novo or inherited recessive or X-linked variants in plausible candidate genes, which require additional validation to determine pathogenicity. Our diagnostic yield of 10% is comparable to, and supplementary to, the diagnostic yield of existing microarray testing for large chromosomal rearrangements and targeted CNV detection. The de novo nature of these events could enable couples to be counseled as to their low recurrence risk. This study outlines the way for a substantial improvement in the diagnostic yield of prenatal genetic abnormalities through the application of next-generation sequencing.
Carss, Keren J.; Hillman, Sarah C.; Parthiban, Vijaya; McMullan, Dominic J.; Maher, Eamonn R.; Kilby, Mark D.; Hurles, Matthew E.
Direct detection of common and rare inversion mutations in the genetic diagnosis of severe hemophilia A
Approximately 50% of the cases of severe hemophilia A (factor VIII:C < 0.01 units/ml) may be due to gross rearrangements of the factor VIII gene. The mutation involves homologous sequences upstream of the factor VIII locus and within intron 22 in an intrachromosomal recombination, inversion, event. The rearrangements can readily be detected on a Southern blot using a probe that is complementary to sequences from within intron 22. We describe here the analysis of this mutation in 71 severe hemophilia A patients. Thirty two of the patients (45%) showed evidence of a rearrangement. Five different patterns of rearrangements were seen, two of which have previously been described and account for the majority of cases (pattern 1, 70% and pattern 2, 16%). Three other abnormal patterns were observed. The inversion mechanism does not usually result in the loss or gain of any genetic material, but in one patient, in whom a unique rearrangement pattern was observed (pattern 3), we have previously documented a gross deletion which removes exons 1-22 of the factor VII gene as well as sequences 5{prime} to the gene. In another individual a fourth pattern in which an extra 19.0 kb band is present was detected. In this case it is unclear as to whether the rearrangement is responsible for the disease or is simply coincident normal variation. A fifth pattern, in which an extra 16.0 kb band was detected, was observed in a family with a new mutation causing hemophilia A. The affected individual and his mother inherited a de novo rearrangement of the factor VIII gene from his unaffected grandfather, implicating it as the cause of the disease. In conclusion, testing for the factor VIII inversion mutation was positive in approximately 45% of severe hemophiliacs, 72% of whom were isolated cases, and as such should constitute the initial stage in the genetic testing protocol for these patients` families.
Windsor, A.S.; Lillicrap, D.P.; Taylor, S.A.M. [Queen`s Univ., Ontario (Canada)
In vitro fertilization (IVF)
... a child may consider pre-implantation genetic diagnosis (PGD). The procedure is done about 3 -4 days ... According to the American Society for Reproductive Medicine, PGD can help parents decide which embryos to implant, ...
Hereditary Papillary Renal Cell Carcinoma
... for this hereditary cancer syndrome. Preimplantation Genetic Diagnosis (PGD) is a medical procedure done in conjunction with ... transfer embryos which do not have the mutation. PGD has been in use for over a decade, ...
A homozygous double mutation in SMN1: a complicated genetic diagnosis of SMA.
Spinal muscular atrophy (SMA), the most common autosomal recessive cause of infant death, is typically diagnosed by determination of SMN1 copy number. Approximately 3-5% of patients with SMA retain at least one copy of the SMN1 gene carrying pathogenic insertions, deletions, or point mutations. We report a patient with SMA who is homozygous for two mutations carried in cis: an 8 bp duplication (c.48_55dupGGATTCCG; p.Val19fs*24) and a point mutation (c.662C>T; p.Pro221Leu). The consanguineous parents carry the same two mutations within one SMN1 gene copy. We demonstrate that a more accurate diagnosis of the disease is obtained through a novel diagnostic assay and development of a capillary electrophoresis method to determine the copy number of their mutant alleles. This illustrates the complexity of SMN mutations and suggests additional testing (gene sequencing) may be appropriate when based on family lines. PMID:24498607
Histologic and Genetic Advances in Refining the Diagnosis of "Undifferentiated Pleomorphic Sarcoma"
Undifferentiated pleomorphic sarcoma (UPS) is an inclusive term used for sarcomas that defy formal sub-classification. The frequency with which this diagnosis is assigned has decreased in the last twenty years. This is because when implemented, careful histologic assessment, immunohistochemistry, and ultra-structural evaluation can often determine lineage of differentiation. Further attrition in the diagnostic frequency of UPS may arise by using array-comparative genomic hybridization. Gene expression arrays are also of potential use as they permit hierarchical gene clustering. Appraisal of the literature is difficult due to a historical perspective in which specific molecular diagnostic methods were previously unavailable. The American Joint Committee on Cancer (AJCC) classification has changed with different inclusion criteria. Taxonomy challenges also exist with the older term �malignant fibrous histiocytoma� being replaced by �UPS�. In 2010 an analysis of multiple sarcoma expression databases using a 170-gene predictor, re-classified most MFH and �not-otherwise-specified� (NOS) tumors as liposarcomas, leiomyosarcomas or fibrosarcomas. Interestingly, some of the classifier genes are potential molecular therapeutic targets including Insulin-like growth factor 1 (IGF-1), Peroxisome proliferator-activated receptor ? (PPAR?), Nerve growth factor ? (NGF ?) and Fibroblast growth factor receptor (FGFR).
Kelleher, Fergal C.; Viterbo, Antonella
Review of the Lynch syndrome: history, molecular genetics, screening, differential diagnosis, and medicolegal ramifications
More than one million patients will manifest colorectal cancer (CRC) this year of which, conservatively, approximately 3% (~30,700 cases) will have Lynch syndrome (LS), the most common hereditary CRC predisposing syndrome. Each case belongs to a family with clinical needs that require genetic counseling, DNA testing for mismatch repair genes (most frequently MLH1 or MSH2) and screening for CRC. Colonoscopy is mandated, given CRC�s proximal occurrence (70�80% proximal to the splenic flexure). Due to its early age of onset (average 45 years of age), colonoscopy needs to start by age 25, and because of its accelerated carcinogenesis, it should be repeated every 1 to 2 years through age 40 and then annually thereafter. Should CRC occur, subtotal colectomy may be necessary, given the marked frequency of synchronous and metachronous CRC. Because 40�60% of female patients will manifest endometrial cancer, tailored management is essential. Additional extracolonic cancers include ovary, stomach, small bowel, pancreas, hepatobiliary tract, upper uroepithelial tract, brain (Turcot variant) and sebaceous adenomas/carcinomas (Muir-Torre variant). LS explains only 10�25% of familial CRC.
Lynch, HT; Lynch, PM; Lanspa, SJ; Snyder, CL; Lynch, JF; Boland, CR
Genetic parameters for somatic cell score according to udder infection status in Valle del Belice dairy sheep and impact of imperfect diagnosis of infection
Background Somatic cell score (SCS) has been promoted as a selection criterion to improve mastitis resistance. However, SCS from healthy and infected animals may be considered as separate traits. Moreover, imperfect sensitivity and specificity could influence animals' classification and impact on estimated variance components. This study was aimed at: (1) estimating the heritability of bacteria negative SCS, bacteria positive SCS, and infection status, (2) estimating phenotypic and genetic correlations between bacteria negative and bacteria positive SCS, and the genetic correlation between bacteria negative SCS and infection status, and (3) evaluating the impact of imperfect diagnosis of infection on variance component estimates. Methods Data on SCS and udder infection status for 1,120 ewes were collected from four Valle del Belice flocks. The pedigree file included 1,603 animals. The SCS dataset was split according to whether animals were infected or not at the time of sampling. A repeatability test-day animal model was used to estimate genetic parameters for SCS traits and the heritability of infection status. The genetic correlation between bacteria negative SCS and infection status was estimated using an MCMC threshold model, implemented by Gibbs Sampling. Results The heritability was 0.10 for bacteria negative SCS, 0.03 for bacteria positive SCS, and 0.09 for infection status, on the liability scale. The genetic correlation between bacteria negative and bacteria positive SCS was 0.62, suggesting that they may be genetically different traits. The genetic correlation between bacteria negative SCS and infection status was 0.51. We demonstrate that imperfect diagnosis of infection leads to underestimation of differences between bacteria negative and bacteria positive SCS, and we derive formulae to predict impacts on estimated genetic parameters. Conclusions The results suggest that bacteria negative and bacteria positive SCS are genetically different traits. A positive genetic correlation between bacteria negative SCS and liability to infection was found, suggesting that the approach of selecting animals for decreased SCS should help to reduce mastitis prevalence. However, the results show that imperfect diagnosis of infection has an impact on estimated genetic parameters, which may reduce the efficiency of selection strategies aiming at distinguishing between bacteria negative and bacteria positive SCS.
Identification of defensin-encoding genes of Picea glauca: characterization of PgD5, a conserved spruce defensin with strong antifungal activity
Background Plant defensins represent a major innate immune protein superfamily that displays strong inhibitory effects on filamentous fungi. The total number of plant defensins in a conifer species is unknown since there are no sequenced conifer genomes published, however the genomes of several angiosperm species provide an insight on the diversity of plant defensins. Here we report the identification of five new defensin-encoding genes from the Picea glauca genome and the characterization of two of their gene products, named PgD5 and endopiceasin. Results Screening of a P. glauca EST database with sequences of known plant defensins identified four genes with homology to the known P. glauca defensin PgD1, which were designated PgD2-5. Whereas in the mature PgD2-4 only 7�9 amino acids differed from PgD1, PgD5 had only 64% sequence identity. PgD5 was amplified from P. glauca genomic DNA by PCR. It codes for a precursor of 77-amino acid that is fully conserved within the Picea genus and has similarity to plant defensins. Recombinant PgD5, produced in Escherichia coli, had a molecular mass of 5.721 kDa, as determined by mass spectrometry. The PgD5 peptide exhibited strong antifungal activity against several phytopathogens without any effect on the morphology of the treated fungal hyphae, but strongly inhibited hyphal elongation. A SYTOX uptake assay suggested that the inhibitory activity of PgD5 could be associated with altering the permeability of the fungal membranes. Another completely unrelated defensin gene was identified in the EST library and named endopiceasin. Its gene codes for a 6-cysteine peptide that shares high similarity with the fungal defensin plectasin. Conclusions Screening of a P. glauca EST database resulted in the identification of five new defensin-encoding genes. PgD5 codes for a plant defensin that displays non-morphogenic antifungal activity against the phytopathogens tested, probably by altering membrane permeability. PgD5 has potential for application in the plant biotechnology sector. Endopiceasin appears to derive from an endo- or epiphytic fungal strain rather than from the plant itself.
Genetic diagnosis of severe myoclonic epilepsy of infancy (Dravet syndrome) with SCN1A mutations in the Hong Kong Chinese patients.
Epilepsy is a clinically and genetically heterogeneous group of disorders. The advent of molecular genetics brings unprecedented advancement in diagnostic molecular pathology and reduces over-reliance on traditional clinical classification. Severe myoclonic epilepsy of infancy or Dravet syndrome is a catastrophic infantile-onset epilepsy. We report two unrelated Hong Kong Chinese patients with this condition presenting with febrile seizures, epilepsy with different semiologies, psychomotor retardation, and recurrent status epilepticus. Two different mutations were characterised, viz NM_001165963.1: c.680T>G; NP_001159435.1: p.I227S and NM_001165963.1: c.3953T>G; NP_001159435.1: p.L1318R (novel). Genetic characterisation conveys a definitive diagnosis and is important from the perspective of selecting anti-epileptic drug therapy and genetic counselling. PMID:22147323
Mak, Chloe M; Chan, K Y; Yau, Eric K C; Chen, Sammy P L; Siu, W K; Law, C Y; Lam, C W; Chan, Albert Y W
This Genetics activity helps students to understand the basic principles of genetics, including concepts of recessive and dominant alleles, relationships of phenotype to genotype, Punnett squares, and pedigree analysis. The introductory section on inheritance of albinism demonstrates how understanding meiosis and fertilization provides the basis for understanding inheritance and Punnett squares. The next two sections, Coin Toss Genetics and analysis of class data on the sex makeup of sibships, help students understand the probabilistic nature of Punnett square predictions. The final activities analyze the genetics of sickle cell anemia and pedigrees for families with albinism and achondroplasia.
Doherty, Jennifer; Waldron, Ingrid; Poethig, Scott
Conflict between values and technology: perceptions of preimplantation genetic diagnosis among women at increased risk for hereditary breast and ovarian cancer
Members of families affected by hereditary cancer are often concerned about passing on risk to offspring. Preimplantation\\u000a genetic diagnosis is a procedure performed to identify embryos that inherit mutations placing them at risk for hereditary\\u000a conditions. Little is known about attitudes toward the use of this technology among individuals at risk for hereditary breast\\u000a and ovarian cancer. We sought to
Gwendolyn P. Quinn; Susan T. Vadaparampil; Lindsey M. King; Cheryl A. Miree; Sue Friedman
Geoelectrical investigation of old/abandoned, covered landfill sites in urban areas: model development with a genetic diagnosis approach
Geoelectrical methods have an important, albeit difficult role to play in landfill investigations. In the present economic conditions, with the environmentally sensitive regime, adequate desk-study and model development are essential ingredients for a successful site investigation of landfills. This paper attempts to develop a genetic investigative model for old/abandoned landfill sites where the records of operations are not available. The main elements of the model are the site boundaries, age and nature of anthropogenic deposits, depth and dip of the layers of refuse and sealing materials, the integrity and shape of the capping zones or separating walls and basal floor slopes, the position of concealed access roads in the site, the water table (or perched water bodies within the refuse) and the presence of leachate. The attendant geotechnical, hydrogeological, and bio-geochemical constraints at such sites are also incorporated in the model for consistency of practical solutions to landfill problems. The nature of anthropogenic deposits and the spatial-temporal characteristics of leachates are reviewed in a geoelectrical context. The analogy between waste degradation and leaching, and the well-known weathering processes of supergene mineral enrichment and saprolite formation in crystalline rocks is explored, and used to develop a conceptual resistivity-vs.-depth model for landfill sites. The main tenet of the model is that vertical conductivity profiles will attain maximum values in the zone of mineral enrichment near the water table and tail-off away from it. This conceptual resistivity model is shown to be consistent with non-invasive observations in landfill sites in different geographical environments. Power-law relationships are found to exist between some geoelectrically important hydrochemical parameters (fluid conductivity, chloride content and total dissolved solids) in leachates and leachate-contaminated groundwater from some landfill sites. Since some chemical parameters of fill are known to vary consistently with time, a plausible hydrochemical and age-deductive scheme for saturated fill is proposed for geoelectrical models of landfills without significant amounts of metal. Practical suggestions are made for a consistent approach in geoelectrical investigation and diagnosis of old landfill sites. A few field examples are used to illustrate the diagnosis approach.
Meju, Maxwell A.
Medical genetics
This book on the subject of medical genetics is a textbook aimed at a very broad audience: principally, medical students, nursing students, graduate, and undergraduate students. The book is actually a primer of general genetics as applied to humans and provides a well-balanced introduction to the scientific and clinical basis of human genetics. The twelve chapters include: Introduction, Basic Cell Biology, Genetic Variation, Autosomal Dominant and Recessive Inheritance, Sex-linked and Mitochondrial Inheritance, Clinical Cytogenetics, Gene Mapping, Immunogenetics, Cancer Genetics, Multifactorial Inheritance and Common Disease, Genetic Screening, Genetic Diagnosis and Gene Therapy, and Clinical Genetics and Genetic Counseling.
Jorde, L.B.; Carey, J.C.; White, R.L.
Neuroendocrine Tumors of the Gastro-Entero-Pancreatic System: The Role of Early Diagnosis, Genetic Testing and Preventive Surgery
Surgery is the only curative approach in neuroendocrine gastro-entero-pancreatic (GEP) tumors. As cure is highly dependent of tumor size, early diagnosis is a prerequisite for surgical success. Diagnosis of nonfunctioning tumors of the pancreas or midgut origin is due to symptoms related to the tumor burden, thus early diagnosis is mostly incidental. Functioning pancreatic tumors should be operated early in
U. Pl�ckinger; B. Wiedenmann
Specific detection of deleted and non-deleted dystrophin exons together with gender assignment in preimplantation genetic diagnosis of Duchenne muscular dystrophy
rates ranged from 90.2% for exon 6 to 96.7% for exons 8 and 32. At least four of the five sequences were successfully amplified in 95.8% of single cells, and sexing was possible in 98.5%. This 5-plex assay was found to be robust enough to be used in a PGD clinical procedure and was therefore applied to a family whose
A. Girardet; S. Hamamah; H. Dechaud; T. Anahory; C. Coubes; B. Hedon; J. Demaille; M. Claustres
Use of parthenogenetic activation of human oocytes as an experimental model for evaluation of polar body based PGD assay performance
Purpose��To develop an experimental model to assess the feasibility of polar body preimplantation genetic diagnosis without requiring\\u000a oocyte fertilization.\\u000a \\u000a \\u000a \\u000a \\u000a Methods��First polar body was removed from donated oocytes and second polar body was biopsied after parthenogenetic activation. Molecular\\u000a analysis on both polar bodies involved a fluorescent multiplex polymerase chain reaction of short-tandem repeat markers, closely\\u000a linked to genes of interest. Main
Alessio Paffoni; Valentina Paracchini; Stefania Ferrari; Claudia Scarduelli; Manuela Seia; Domenico A. Coviello; Guido Ragni
Genetic Diagnosis of Familial Hypercholesterolemia in a South European Outbreed Population: Influence of Low Density Lipoprotein (LDL) Receptor Gene Mutations on Treatment Response to Simvastatin in Total, LDL, and High-Density Lipoprotein Cholesterol
The aims of this study were to examine the presence of mu- tations in the low-density lipoprotein receptor gene among subjects clinically diagnosed with familial hypercholesterol- emia and to analyze whether the molecular diagnosis helps to predict the response to simvastatin treatment in our familial hypercholesterolemia population. Fifty-five probands and 128 related subjects with familial hypercholesterolemia were studied. Genetic diagnosis
learning about our genetic make up We've been learning about DNA. Go to each web site, read and follow the instructions of the activities provided. On a piece of paper write your answers to the following questions and submit your work. Put the site for each of the questions you are answering. The first site is, ...
Curran, Carolyn
Observations of phase transitions in the mixed crystal system Dy pGd 1-pVO 4
The low temperature crystallographic and magnetic phase transitions in the mixed crystal system Dy pGd 1- pVO 4 (0 ? p ? 1) have been studied using thermal expansion measurements and M�ssbauer spectroscopy. The introduction of magnetic Gd 3+ ions into the DyVO 4 host causes an anomalous dip in the N�el temperature T N( p), and a rapid reduction of the distortion temperature T D( p) which differs from results on similar mixed systems. A number of pseudo-spin Hamiltonians that model these observations are discussed.
Bingham, D.; Morgan, M. J.; Cashion, J. D.
The genetic basis of modulation by dietary sucrose of the enzyme activities glucose 6-phosphate dehydrogenase (GGPD) and 6-phosphogluconate dehydro- genase (6PGD) activities in third instar larvae of Drosophila melanogaster was investigated, using isogenic lines derived from wild populations. Considerable genetically determined variation in response was detected among lines that differed only in their third chromosome constitution. Comparison of cross- reacting
Prune-belly syndrome: case series and review of the literature regarding early prenatal diagnosis, epidemiology, genetic factors, treatment, and prognosis.
Prune-belly syndrome (PBS) is a rare congenital syndrome characterized by deficient abdominal muscles, urinary tract malformation, and in males, cryptorchidism and has an estimated incidence of 1 in 35,000 to 1 in 50,000 live births. The syndrome might be due to severe bladder outlet obstruction or to abdominal muscle deficiency secondary to a migrational defect of the lateral mesoblast between weeks 6 and 7 of pregnancy. The current review of the medical record reports a special focus on epidemiology, genetic factors, early prenatal diagnosis clusters, treatment, and prognosis of PBS. PMID:22506933
Tonni, Gabriele; Ida, Vito; Alessandro, Ventura; Bonasoni, Maria Paola
Polymorphism at the G6pd and 6Pgd loci in Drosophila melanogaster. III. Developmental and biochemical aspects.
The electrophoretic variants of G6PD and 6PGD isolated from the Bogota Drosophila melanogaster population were characterized developmentally and biochemically. Changes in in vitro enzyme activity during development were comparable to those found for other dehydrogenases: an increase in the larval and adult stage and a decrease in the pupal stage. During the whole life cycle the "S" enzyme of both loci showed a higher activity than the "F" enzyme. MgCl2 had a stimulating effect on the activity of both enzymes whereas their heat stability was decreased. The allozymes of 6PGD had different Vmax's but were comparable with respect to Km values, pH optimum, and stability at 45 C. the allozymes of G6PD showed different Vmax's and differed in stability at 35 C, but had similar Km values and pH optima. As the difference in stability was probably due to differences in molecular structure of the allozymes, the differences in activity found at high pH and high MgCl2 concentration were most probably due to this difference in stability. PMID:44188
Bijlsma, R; van der Meulen-Bruijns, C
"Important to test, important to support": attitudes toward disability rights and prenatal diagnosis among leaders of support groups for genetic disorders in Israel.
To situate the North American, and to some extent, European debate regarding disability rights and prenatal diagnosis in a social and cross-cultural context, this pilot study explored the views of leaders of organizations for disability rights and support groups for people with genetic conditions in Israel, where a similar debate has not emerged. Unlike many of their counterparts in North America, Israeli respondents were generally in favor of prenatal genetic testing as well as selective abortion, while at the same time expressing their commitment for already-born disabled individuals. The religious, legal, economic and socio-cultural context of this two-fold view of disability--which separates prenatal (preventive testing) and postnatal (supporting disability)--is discussed in order to further situate the debate in cross-cultural perspective. It is hypothesized that prenatal diagnosis and selective abortion are supported in secular Israeli society independently of the rabbinical stance, which forbids selective abortion, and in a way that reflects society's non-acceptance of congenital disability, veneration of the healthy body, and medical directiveness. PMID:15312920
Raz, Aviad
Preimplantation Polar Body Diagnosis
Preimplantation polar body diagnosis makes it possible to detect and avoid genetic and chromosomal disorders before pregnancy. We have shown that the polar body biopsy does not affect fertilization and viability of the resulting embryos. Our present experience of polar body diagnosis includes 187 clinical cycles, performed for preimplantation diagnosis of cystic fibrosis, ?-1-antitrypsin deficiency, Tay-Sach's disease, retinitis pigmentosa, hemophilia
Genetic technology: Promises and problems
NASA Technical Reports Server (NTRS)
Issues concerning the use of genetic technology are discussed. Some areas discussed include treating genetic disease, prenatal diagnosis and selective abortion, screening for genetic disease, and genetic counseling. Policy issues stemming from these capabilities are considered.
Frankel, M. S.
Genetic characterization of Epimedium species using random amplified polymorphic DNA (RAPD) and PCR-restriction fragment length polymorphism (RFLP) diagnosis.
Total DNA was extracted from the leaves of seven Epimedium species grown in different places in Japan. Their genetic characterization was performed by DNA analyses of random amplified polymorphic DNA (RAPD) using 32 random primers having 10 base sequences, and by restriction fragment length polymorphism (RFLP). E. sagittatum and E. koreanum were easily distinguished by a representative amplified band pattern. It became evident that E. sagittatum had extremely different genetic composition compared to the other species. A dendrogram obtained from the similarity matrix by cluster analysis indicates that E. sagittatum can be completely isolated from the other species. Moreover, it became evident that E. grandiflorum var. higoense, E. trifoliatobinatum and E. koreanum are independent species, contrary to the previous assumption that they are subspecies or a variety. The geographical variation of E. sempervirens was confirmed by cluster analysis. E. diphyllum showed wide genetic variations, in spite of sampling from the same area. PMID:8820914
Nakai, R; Shoyama, Y; Shiraishi, S
A Family Perspective of the Value of a Diagnosis for Intellectual Disability: Experiences from a Genetic Research Study
Many professionals working with individuals with intellectual disability are unconcerned with why someone has the impairment. Genetic aspects may be viewed as, at best irrelevant, but more often, potentially negative. However, where the intellectual disability may be inherited, there are implications for family members and the individual. The data�
Statham, Helen; Ponder, Maggie; Richards, Martin; Hallowell, Nina; Raymond, Frances Lucy
Developing a Knowledge-Based System Using Rough Set Theory and Genetic Algorithms for Substation Fault Diagnosis
Supervisory Control and Data Acquisition (SCADA) systems are fundamental tools for quick fault diagnosis and efficient restoration\\u000a of power systems. When multiple faults, or malfunctions of protection devices occur in the system, the SCADA system issues\\u000a many alarm signals rapidly and relays these to the control center. The original cause and location of the fault can be difficult\\u000a to determine
Ching Lai Hor; Peter Crossley; Simon Watson; Dean Millar
Genetic polymorphisms of multiple DNA repair pathways impact age at diagnosis and TP53 mutations in breast cancer
Defective DNA repair may contribute to early age and late stage at time of diagnosis and mutations in critical tumor suppressor genes, such as TP53 in breast cancer. Using DNA samples from 436 breast cancer cases (374 Caucasians and 62 African-Americans), we tested these associations with 18 non-synonymous single-nucleotide polymorphisms (nsSNPs) in four DNA repair pathways: (i) base excision repair: ADPRT V762A, APE1 D148E, XRCC1 R194W/R280H/R399Q and POLD1 R119H; (ii) double-strand break repair: NBS1 E185Q and XRCC3 T241M; (iii) mismatch repair: MLH1 I219V, MSH3 R940Q/T1036A and MSH6 G39E and (iv) nucleotide excision repair: ERCC2 D312N/K751Q, ERCC4 R415Q, ERCC5 D1104H and XPC A499V/K939Q. Younger age at diagnosis (<50) was associated with ERCC2 312 DN/NN genotypes [odds ratio (OR) = 1.76; 95% confidence interval (CI) = 1.10, 2.81] and NBS1 185 QQ genotype (OR = 3.09; 95% CI = 1.47, 6.49). The XPC 939 QQ genotype was associated with TP53 mutations (OR = 5.80; 95% CI = 2.23, 15.09). There was a significant trend associating younger age at diagnosis (<50) with increasing numbers of risk genotypes for ERCC2 312 DN/NN, MSH6 39 EE and NBS1 185 QQ (Ptrend < 0.001). A similar significant trend was also observed associating TP53 mutations with increasing numbers of risk genotypes for XRCC1 399 QQ, XPC 939 QQ, ERCC4 415 QQ and XPC 499 AA (Ptrend < 0.001). Our pilot data suggest that nsSNPs of multiple DNA repair pathways are associated with younger age at diagnosis and TP53 mutations in breast cancer and larger studies are warranted to further evaluate these associations.
Smith, Tasha R.; Liu-Mares, Wen; Van Emburgh, Beth O.; Levine, Edward A.; Allen, Glenn O.; Hill, Jeff W.; Reis, Isildinha M.; Kresty, Laura A.; Pegram, Mark D.; Hu, Jennifer J.
Distinct outcomes of chloride diarrhoea in two siblings with identical genetic background of the disease: implications for early diagnosis and treatment
BACKGROUND�Congenital chloride diarrhoea (CLD, OMIM 214700) is a serious inherited defect of intestinal electrolyte absorption transmitted in an autosomal recessive fashion. The major clinical manifestation is diarrhoea with high chloride content which can be balanced by substitution. The molecular pathology involves an epithelial Cl /HCO3 exchanger protein, encoded by the solute carrier family 26,�member 3�gene (SLC26A3), previously known as CLD or DRA (downregulated in adenomas). To date, almost 30�different mutations in the SLC26A3 gene have been identified throughout the world. No clear genotype-phenotype correlation has been established.?PATIENTS/METHODS�Two siblings presenting with CLD were studied for disease history, supplementation, or other treatments, and for mutations in the SLC26A3 gene.?RESULTS�Mutation analysis revealed a homozygous I544N mutation in both patients. However, despite the uniform genetic background of CLD in this family, the clinical picture and outcome of the disease were remarkably different between siblings. The older sibling had a late diagnosis and chronic course of the disease whereas the younger one, who was diagnosed soon after birth and immediately received supplementation therapy, grows and develops normally.?CONCLUSION�Time of diagnosis, substitution therapy, compliance, and compensatory mechanisms are more important modulators of the clinical picture of CLD than the type of mutation in the SLC26A3 gene.???Keywords: chloride diarrhoea; SLC26A3 gene;
Hoglund, P; Holmberg, C; Sherman, P; Kere, J
Challenges in virological diagnosis of HIV -1 transmission from sexual abuse--HIV-1 genetic links are mandatory.
The purpose of this article is to set forth possible strategies and techniques of analysis to diagnose or identify the source of HIV transmission in victims of sexual abuse. Diagnosis of HIV-1 transmission from sexual abuse is complicated. Timely blood samples are important. The right to confidentiality of the HIV diagnosis may prevent sampling from the offender. Hideous rapes occur during war, which victimize many women. Women delivering a child, seeking an abortion, or having a miscarriage may include victims of sexual abuse. HIV-infected children, where vertical transmission has been excluded, are important for investigation. Men who have sex with men may abuse young men. HIV-infected teenagers with signs of early infection should also be considered. Hundreds of single HIV-1 sequences can be created from one or more blood samples from the case and the alleged abuser. The more HIV-1 genes and sequences that are included, the better the outcomes of the phylogenetic relation. Evidence in support of transmission may be obtained from phylogenetic tree analysis and may also free someone from suspicion. PMID:23387930
Ehrnst, Anneka
New diagnosis of multiple myeloma in a patient with mantle cell lymphoma: Shared genetic factors or simple coincidence?
Multiple Myeloma and Mantle Cell Lymphoma are well defined hematological malignancies. Understanding of their pathogeneses has led to new therapies and increased survival. We report on a 64-yr-old female who was diagnosed with mantle cell lymphoma in 2003, then multiple myeloma in 2010. We identified only few other cases of concomitant MM and MCL. We also explored the importance of t(11;14)(q13;q32). The development of these two disorders in the same patient may simply be due to chance; however, it may also represent a common genetic hit affecting the B-cell population leading to development of two different malignancies.
Sikuyayenga, Mutende J.; Reeder, Craig B.; Mikhael, Joseph R.
Genetic diagnosis of Hailey-Hailey disease in two Chinese families: novel mutations in the ATP2C1 gene.
Hailey-Hailey disease (HHD; OMIM 169600), is an autosomal dominantly inherited disorder characterized by suprabasal cell separation of the epidermis. Mutations in ATP2C1, which encodes the human secretory pathway Ca(2+)/ Mn(2) +/- ATPase protein 1 (hSPCA1), have been identified as the pathogenic gene of HHD without evidence of genetic heterogeneity. In this study, the ATP2C1 gene was screened in two typical Chinese pedigrees with HHD, and two specific novel mutations of the ATP2CL gene were identified. Family 1 had a 16-base deletion mutation c.1068-1083del16 and family 2 had a substitution mutation c.1982T>G (p.Met661Arg). DNA sequencing of the three descendants of the probands revealed that they all had the normal genotype, indicating that there had been no transmission of the mutation. PMID:20055875
Ding, Y G; Fang, H; Lao, L M; Jiang, X J; Chen, H C
Infantile-onset glycogen storage disease type II (Pompe disease): report of a case with genetic diagnosis and pathological findings.
Glycogen storage disease type II (GSD-II), also known as Pompe disease, is a rare autosomial recessive disease due to deficiency of lysosomal acid alpha-glucosidase (GAA). The infantile-onset form is the most severe, and most patients present with hypotonia and cardiomyopathy in early infancy. We report on a typical case of Pompe disease in a patient who died at 8 months of age due to aspiration pneumonia and hypertrophic cardiomyopathy. Genetic studies showed deficient GAA activity and mutation of the GAA gene with Gly615Arg (exon 13, G1845A). On autopsy, glycogen had markedly accumulated in the liver, myocardium and skeletal muscle. The neurons of the anterior horn of the spinal cord and medulla were also involved, but the cortex was spared. These neurological-histologic findings may explain the clinical features of poor motor function, decreased deep tendon reflexes and lack of mental retardation. PMID:15366815
Teng, Yao-Tun; Su, Wen-Jen; Hou, Jia-Wei; Huang, Shiu-Feng
Accurate and rapid novel genetic diagnosis for detection of sentinel lymph node metastasis in breast cancer patients
Background: The transcription-reverse transcription concerted reaction (TRC) test is a novel molecular-based procedure, which can assess nodal metastasis accurately and quickly. We examined the usefulness of the TRC test with a double marker, cytokeratin 19 (CK19) and carcinoembryonic antigen (CEA) mRNA, to detect sentinel lymph nodes (SLN) metastasis in breast cancer patients. Methods: A total of 264 SLNs from 131 breast cancer patients were assigned to a training set (109 SLNs from 50 patients) and validation set (155 SLNs from 81 patients). Cytokeratin 19 and CEA mRNA were detected by TRC tests, and the sensitivity and specificity of the SLN metastasis between the TRC and histology cohorts were compared. Results: Mean copy numbers of CK19 and CEA by TRC tests were increased according to the metastatic size. In the training set, TRC test showed 100% sensitivity, specificity and concordance rates against the permanent histopathology test. In the validation set, sensitivity was 97.1%, specificity was 99.2% and the concordance rate was 99.4%. Conclusion: Our results showed that the detection of CK19 and CEA mRNA using the TRC test is, an accurate and rapid method for detection of SLN metastasis and can be applied as an intraoperative molecular diagnosis in breast cancer patients.
Iinuma, H; Tamura, J; Omoto, D; Kamo, N; Ohnaka, S; Mitoma, Y; Miyazawa, Y; Okinaga, K; Imamura, T; Fukushima, R; Watanabe, T; Ikeda, T
Le diagnostic pr�implantatoire coupl� au typage HLA : l'exp�rience parisienne
Preimplantation genetic diagnosis (PGD) consists in the genetic analysis of one or two cells. These cells (blastomeres) are sampled from embryos, obtained by in vitro fertilization, at the third day of development. Since 1998, the bioethical laws (1994) and their decrees restricted PGD practices in France, strictly to the avoidance of the birth of a child affected with a genetic
J. Steffann; N. Frydman; P. Burlet; N. Gigarel; E. Feyereisen; V. Kerbrat; G. Tachdjian; A. Munnich; R. Frydman
Visna/Maedi virus genetic characterization and serological diagnosis of infection in sheep from a neurological outbreak.
An extensive outbreak characterized by the appearance of neurological symptoms in small ruminant lentivirus (SRLV) infected sheep has been identified in Spain, but the genetic characteristics of the strain involved and differential diagnostic tools for this outbreak remain unexplored. In this work, 23 Visna-affected naturally infected animals from the outbreak, 11 arthritic animals (both groups presenting anti-Visna/Maedi virus serum antibodies), and 100 seronegative animals were used. Eight of the Visna-affected animals were further studied post-mortem by immunohistochemistry. All had lesions in spinal cord, being the most affected part of the central nervous system in six of them. A representative strain of the outbreak was isolated. Together with other proviral sequences from the outbreak the virus was assigned to genotype A2/A3. In vitro culture of the isolate revealed that viral production was slow/low in fibroblast-like cells but it was high in blood monocyte-derived macrophages. The long terminal repeat (LTR) of the viral genome of this isolate lacked an U3-duplication, but its promoter activity in fibroblast-like cells was normal compared to other strains. Thus, viral production could not be inferred from the LTR promoter activity in this isolate. Analysis of the viral immunodominant epitopes among SRLV sequences of the outbreak and other known sequences allowed the design of a synthetic SU peptide ELISA that detected the Visna affected animals, representing a tool of epidemiological interest to control viral spread of this highly pathogenic strain. PMID:21940116
Glaria, I; Reina, R; Ram�rez, H; de Andr�s, X; Crespo, H; Jauregui, P; Salazar, E; Luj�n, L; P�rez, M M; Benavides, J; P�rez, V; Polledo, L; Garc�a-Mar�n, J F; Riezu, J I; Borr�s, F; Amorena, B; de Andr�s, D