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What is (are) Majeed syndrome ?
Majeed syndrome is a rare condition characterized by recurrent episodes of fever and inflammation in the bones and skin. One of the major features of Majeed syndrome is an inflammatory bone condition known as chronic recurrent multifocal osteomyelitis (CRMO). This condition causes recurrent episodes of pain and joint swelling beginning in infancy or early childhood. These symptoms persist into adulthood, although they may improve for short periods. CRMO can lead to complications such as slow growth and the development of joint deformities called contractures, which restrict the movement of certain joints. Another feature of Majeed syndrome is a blood disorder called congenital dyserythropoietic anemia. This disorder is one of many types of anemia, all of which involve a shortage of red blood cells. Without enough of these cells, the blood cannot carry an adequate supply of oxygen to the body's tissues. The resulting symptoms can include tiredness (fatigue), weakness, pale skin, and shortness of breath. Complications of congenital dyserythropoietic anemia can range from mild to severe. Most people with Majeed syndrome also develop inflammatory disorders of the skin, most often a condition known as Sweet syndrome. The symptoms of Sweet syndrome include fever and the development of painful bumps or blisters on the face, neck, back, and arms.
Majeed syndrome
How many people are affected by Majeed syndrome ?
Majeed syndrome appears to be very rare; it has been reported in three families, all from the Middle East.
Majeed syndrome
What are the genetic changes related to Majeed syndrome ?
Majeed syndrome results from mutations in the LPIN2 gene. This gene provides instructions for making a protein called lipin-2. Researchers believe that this protein may play a role in the processing of fats (lipid metabolism). However, no lipid abnormalities have been found with Majeed syndrome. Lipin-2 also may be involved in controlling inflammation and in cell division. Mutations in the LPIN2 gene alter the structure and function of lipin-2. It is unclear how these genetic changes lead to bone disease, anemia, and inflammation of the skin in people with Majeed syndrome.
Majeed syndrome
Is Majeed syndrome inherited ?
This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene. Although carriers typically do not show signs and symptoms of the condition, some parents of children with Majeed syndrome have had an inflammatory skin disorder called psoriasis.
Majeed syndrome
What are the treatments for Majeed syndrome ?
These resources address the diagnosis or management of Majeed syndrome: - Gene Review: Gene Review: Majeed Syndrome - Genetic Testing Registry: Majeed syndrome - MedlinePlus Encyclopedia: Osteomyelitis - MedlinePlus Encyclopedia: Psoriasis These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
Majeed syndrome
What is (are) renal coloboma syndrome ?
Renal coloboma syndrome (also known as papillorenal syndrome) is a condition that primarily affects kidney (renal) and eye development. People with this condition typically have kidneys that are small and underdeveloped (hypoplastic), which can lead to end-stage renal disease (ESRD). This serious disease occurs when the kidneys are no longer able to filter fluids and waste products from the body effectively. It has been estimated that approximately ten percent of children with hypoplastic kidneys may have renal coloboma syndrome. The kidney problems can affect one or both kidneys. Additionally, people with renal coloboma syndrome may have a malformation in the optic nerve, a structure that carries information from the eye to the brain. Optic nerve malformations are sometimes associated with a gap or hole (coloboma) in the light-sensitive tissue at the back of the eye (the retina). The vision problems caused by these abnormalities can vary depending on the size and location of the malformation. Some people have no visual problems, while others may have severely impaired vision. Less common features of renal coloboma syndrome include backflow of urine from the bladder (vesicoureteral reflux), multiple kidney cysts, loose joints, and mild hearing loss.
renal coloboma syndrome
How many people are affected by renal coloboma syndrome ?
The prevalence of renal coloboma syndrome is unknown; at least 60 cases have been reported in the scientific literature.
renal coloboma syndrome
What are the genetic changes related to renal coloboma syndrome ?
Renal coloboma syndrome is caused by mutations in the PAX2 gene. The PAX2 gene provides instructions for making a protein that is involved in the early development of the eyes, ears, brain and spinal cord (central nervous system), kidneys, and genital tract. The PAX2 protein attaches (binds) to specific regions of DNA and regulates the activity of other genes. On the basis of this role, the PAX2 protein is called a transcription factor. After birth, the PAX2 protein is thought to protect against cell death during periods of cellular stress. Mutations in the PAX2 gene lead to the production of a nonfunctional PAX2 protein that is unable to aid in development, causing incomplete formation of certain tissues. Why the kidneys and eyes are specifically affected by PAX2 gene mutations is unclear. Approximately half of those affected with renal coloboma syndrome do not have an identified mutation in the PAX2 gene. In these cases, the cause of the disorder is unknown.
renal coloboma syndrome
Is renal coloboma syndrome inherited ?
This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder.
renal coloboma syndrome
What are the treatments for renal coloboma syndrome ?
These resources address the diagnosis or management of renal coloboma syndrome: - Gene Review: Gene Review: Renal Coloboma Syndrome - Genetic Testing Registry: Renal coloboma syndrome These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
renal coloboma syndrome
What is (are) 22q11.2 duplication ?
22q11.2 duplication is a condition caused by an extra copy of a small piece of chromosome 22. The duplication occurs near the middle of the chromosome at a location designated q11.2. The features of this condition vary widely, even among members of the same family. Affected individuals may have developmental delay, intellectual disability, slow growth leading to short stature, and weak muscle tone (hypotonia). Many people with the duplication have no apparent physical or intellectual disabilities.
22q11.2 duplication
How many people are affected by 22q11.2 duplication ?
The prevalence of the 22q11.2 duplication in the general population is difficult to determine. Because many individuals with this duplication have no associated symptoms, their duplication may never be detected. Most people tested for the 22q11.2 duplication have come to medical attention as a result of developmental delay or other problems affecting themselves or a family member. In one study, about 1 in 700 people tested for these reasons had the 22q11.2 duplication. Overall, more than 60 individuals with the duplication have been identified.
22q11.2 duplication
What are the genetic changes related to 22q11.2 duplication ?
People with 22q11.2 duplication have an extra copy of some genetic material at position q11.2 on chromosome 22. In most cases, this extra genetic material consists of a sequence of about 3 million DNA building blocks (base pairs), also written as 3 megabases (Mb). The 3 Mb duplicated region contains 30 to 40 genes. For many of these genes, little is known about their function. A small percentage of affected individuals have a shorter duplication in the same region. Researchers are working to determine which duplicated genes may contribute to the developmental delay and other problems that sometimes affect people with this condition.
22q11.2 duplication
Is 22q11.2 duplication inherited ?
The inheritance of 22q11.2 duplication is considered autosomal dominant because the duplication affects one of the two copies of chromosome 22 in each cell. About 70 percent of affected individuals inherit the duplication from a parent. In other cases, the duplication is not inherited and instead occurs as a random event during the formation of reproductive cells (eggs and sperm) or in early fetal development. These affected people typically have no history of the disorder in their family, although they can pass the duplication to their children.
22q11.2 duplication
What are the treatments for 22q11.2 duplication ?
These resources address the diagnosis or management of 22q11.2 duplication: - Gene Review: Gene Review: 22q11.2 Duplication - Genetic Testing Registry: 22q11.2 duplication syndrome These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
22q11.2 duplication
What is (are) short QT syndrome ?
Short QT syndrome is a condition that can cause a disruption of the heart's normal rhythm (arrhythmia). In people with this condition, the heart (cardiac) muscle takes less time than usual to recharge between beats. The term "short QT" refers to a specific pattern of heart activity that is detected with an electrocardiogram (EKG), which is a test used to measure the electrical activity of the heart. In people with this condition, the part of the heartbeat known as the QT interval is abnormally short. If untreated, the arrhythmia associated with short QT syndrome can lead to a variety of signs and symptoms, from dizziness and fainting (syncope) to cardiac arrest and sudden death. These signs and symptoms can occur any time from early infancy to old age. This condition may explain some cases of sudden infant death syndrome (SIDS), which is a major cause of unexplained death in babies younger than 1 year. However, some people with short QT syndrome never experience any health problems associated with the condition.
short QT syndrome
How many people are affected by short QT syndrome ?
Short QT syndrome appears to be rare. At least 70 cases have been identified worldwide since the condition was discovered in 2000. However, the condition may be underdiagnosed because some affected individuals never experience symptoms.
short QT syndrome
What are the genetic changes related to short QT syndrome ?
Mutations in the KCNH2, KCNJ2, and KCNQ1 genes can cause short QT syndrome. These genes provide instructions for making channels that transport positively charged atoms (ions) of potassium out of cells. In cardiac muscle, these ion channels play critical roles in maintaining the heart's normal rhythm. Mutations in the KCNH2, KCNJ2, or KCNQ1 gene increase the activity of the channels, which enhances the flow of potassium ions across the membrane of cardiac muscle cells. This change in ion transport alters the electrical activity of the heart and can lead to the abnormal heart rhythms characteristic of short QT syndrome. Some affected individuals do not have an identified mutation in the KCNH2, KCNJ2, or KCNQ1 gene. Changes in other genes that have not been identified may cause the disorder in these cases.
short QT syndrome
Is short QT syndrome inherited ?
Short QT syndrome appears to have an autosomal dominant pattern of inheritance, which means one copy of the altered gene in each cell is sufficient to cause the disorder. Some affected individuals have a family history of short QT syndrome or related heart problems and sudden cardiac death. Other cases of short QT syndrome are classified as sporadic and occur in people with no apparent family history of related heart problems.
short QT syndrome
What are the treatments for short QT syndrome ?
These resources address the diagnosis or management of short QT syndrome: - Genetic Testing Registry: Short QT syndrome 1 - Genetic Testing Registry: Short QT syndrome 2 - Genetic Testing Registry: Short QT syndrome 3 - MedlinePlus Encyclopedia: Arrhythmias These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
short QT syndrome
What is (are) congenital hemidysplasia with ichthyosiform erythroderma and limb defects ?
Congenital hemidysplasia with ichthyosiform erythroderma and limb defects, more commonly known by the acronym CHILD syndrome, is a condition that affects the development of several parts of the body. The signs and symptoms of this disorder are typically limited to either the right side or the left side of the body. ("Hemi-" means "half," and "dysplasia" refers to abnormal growth.) The right side is affected about twice as often as the left side. People with CHILD syndrome have a skin condition characterized by large patches of skin that are red and inflamed (erythroderma) and covered with flaky scales (ichthyosis). This condition is most likely to occur in skin folds and creases and usually does not affect the face. The skin abnormalities are present at birth and persist throughout life. CHILD syndrome also disrupts the formation of the arms and legs during early development. Children with this disorder may be born with one or more limbs that are shortened or missing. The limb abnormalities occur on the same side of the body as the skin abnormalities. Additionally, CHILD syndrome may affect the development of the brain, heart, lungs, and kidneys.
congenital hemidysplasia with ichthyosiform erythroderma and limb defects
How many people are affected by congenital hemidysplasia with ichthyosiform erythroderma and limb defects ?
CHILD syndrome is a rare disorder; it has been reported in about 60 people worldwide. This condition occurs almost exclusively in females.
congenital hemidysplasia with ichthyosiform erythroderma and limb defects
What are the genetic changes related to congenital hemidysplasia with ichthyosiform erythroderma and limb defects ?
Mutations in the NSDHL gene cause CHILD syndrome. This gene provides instructions for making an enzyme that is involved in the production of cholesterol. Cholesterol is a type of fat that is produced in the body and obtained from foods that come from animals, particularly egg yolks, meat, fish, and dairy products. Although high cholesterol levels are a well-known risk factor for heart disease, the body needs some cholesterol to develop and function normally both before and after birth. Cholesterol is an important component of cell membranes and the protective substance covering nerve cells (myelin). Additionally, cholesterol plays a role in the production of certain hormones and digestive acids. The mutations that underlie CHILD syndrome eliminate the activity of the NSDHL enzyme, which disrupts the normal production of cholesterol within cells. A shortage of this enzyme may also allow potentially toxic byproducts of cholesterol production to build up in the body's tissues. Researchers suspect that low cholesterol levels and/or an accumulation of other substances disrupt the growth and development of many parts of the body. It is not known, however, how a disturbance in cholesterol production leads to the specific features of CHILD syndrome.
congenital hemidysplasia with ichthyosiform erythroderma and limb defects
Is congenital hemidysplasia with ichthyosiform erythroderma and limb defects inherited ?
This condition has an X-linked dominant pattern of inheritance. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. The inheritance is dominant if one copy of the altered gene in each cell is sufficient to cause the condition. Most cases of CHILD syndrome occur sporadically, which means only one member of a family is affected. Rarely, the condition can run in families and is passed from mother to daughter. Researchers believe that CHILD syndrome occurs almost exclusively in females because affected males die before birth. Only one male with CHILD syndrome has been reported.
congenital hemidysplasia with ichthyosiform erythroderma and limb defects
What are the treatments for congenital hemidysplasia with ichthyosiform erythroderma and limb defects ?
These resources address the diagnosis or management of CHILD syndrome: - Gene Review: Gene Review: NSDHL-Related Disorders - Genetic Testing Registry: Child syndrome These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
congenital hemidysplasia with ichthyosiform erythroderma and limb defects
What is (are) congenital leptin deficiency ?
Congenital leptin deficiency is a condition that causes severe obesity beginning in the first few months of life. Affected individuals are of normal weight at birth, but they are constantly hungry and quickly gain weight. Without treatment, the extreme hunger continues and leads to chronic excessive eating (hyperphagia) and obesity. Beginning in early childhood, affected individuals develop abnormal eating behaviors such as fighting with other children over food, hoarding food, and eating in secret. People with congenital leptin deficiency also have hypogonadotropic hypogonadism, which is a condition caused by reduced production of hormones that direct sexual development. Without treatment, affected individuals experience delayed puberty or do not go through puberty, and may be unable to conceive children (infertile).
congenital leptin deficiency
How many people are affected by congenital leptin deficiency ?
Congenital leptin deficiency is a rare disorder. Only a few dozen cases have been reported in the medical literature.
congenital leptin deficiency
What are the genetic changes related to congenital leptin deficiency ?
Congenital leptin deficiency is caused by mutations in the LEP gene. This gene provides instructions for making a hormone called leptin, which is involved in the regulation of body weight. Normally, the body's fat cells release leptin in proportion to their size. As fat accumulates in cells, more leptin is produced. This rise in leptin indicates that fat stores are increasing. Leptin attaches (binds) to and activates a protein called the leptin receptor, fitting into the receptor like a key into a lock. The leptin receptor protein is found on the surface of cells in many organs and tissues of the body including a part of the brain called the hypothalamus. The hypothalamus controls hunger and thirst as well as other functions such as sleep, moods, and body temperature. It also regulates the release of many hormones that have functions throughout the body. In the hypothalamus, the binding of leptin to its receptor triggers a series of chemical signals that affect hunger and help produce a feeling of fullness (satiety). LEP gene mutations that cause congenital leptin deficiency lead to an absence of leptin. As a result, the signaling that triggers feelings of satiety does not occur, leading to the excessive hunger and weight gain associated with this disorder. Because hypogonadotropic hypogonadism occurs in congenital leptin deficiency, researchers suggest that leptin signaling is also involved in regulating the hormones that control sexual development. However, the specifics of this involvement and how it may be altered in congenital leptin deficiency are unknown. Congenital leptin deficiency is a rare cause of obesity. Researchers are studying the factors involved in more common forms of obesity.
congenital leptin deficiency
Is congenital leptin deficiency inherited ?
This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
congenital leptin deficiency
What are the treatments for congenital leptin deficiency ?
These resources address the diagnosis or management of congenital leptin deficiency: - Eunice Kennedy Shriver National Institute of Child Health and Human Development: How Are Obesity and Overweight Diagnosed? - Genetic Testing Registry: Obesity, severe, due to leptin deficiency - Genetics of Obesity Study - National Heart, Lung, and Blood Institute: How Are Overweight and Obesity Treated? These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
congenital leptin deficiency
What is (are) lysinuric protein intolerance ?
Lysinuric protein intolerance is a disorder caused by the body's inability to digest and use certain protein building blocks (amino acids), namely lysine, arginine, and ornithine. Because the body cannot effectively break down these amino acids, which are found in many protein-rich foods, nausea and vomiting are typically experienced after ingesting protein. People with lysinuric protein intolerance have features associated with protein intolerance, including an enlarged liver and spleen (hepatosplenomegaly), short stature, muscle weakness, impaired immune function, and progressively brittle bones that are prone to fracture (osteoporosis). A lung disorder called pulmonary alveolar proteinosis may also develop. This disorder is characterized by protein deposits in the lungs, which interfere with lung function and can be life-threatening. An accumulation of amino acids in the kidneys can cause end-stage renal disease (ESRD) in which the kidneys become unable to filter fluids and waste products from the body effectively. A lack of certain amino acids can cause elevated levels of ammonia in the blood. If ammonia levels are too high for too long, they can cause coma and intellectual disability. The signs and symptoms of lysinuric protein intolerance typically appear after infants are weaned and receive greater amounts of protein from solid foods.
lysinuric protein intolerance
How many people are affected by lysinuric protein intolerance ?
Lysinuric protein intolerance is estimated to occur in 1 in 60,000 newborns in Finland and 1 in 57,000 newborns in Japan. Outside these populations this condition occurs less frequently, but the exact incidence is unknown.
lysinuric protein intolerance
What are the genetic changes related to lysinuric protein intolerance ?
Mutations in the SLC7A7 gene cause lysinuric protein intolerance. The SLC7A7 gene provides instructions for producing a protein called y+L amino acid transporter 1 (y+LAT-1), which is involved in transporting lysine, arginine, and ornithine between cells in the body. The transportation of amino acids from the small intestines and kidneys to the rest of the body is necessary for the body to be able to use proteins. Mutations in the y+LAT-1 protein disrupt the transportation of amino acids, leading to a shortage of lysine, arginine, and ornithine in the body and an abnormally large amount of these amino acids in urine. A shortage of lysine, arginine, and ornithine disrupts many vital functions. Arginine and ornithine are involved in a cellular process called the urea cycle, which processes excess nitrogen (in the form of ammonia) that is generated when protein is used by the body. The lack of arginine and ornithine in the urea cycle causes elevated levels of ammonia in the blood. Lysine is particularly abundant in collagen molecules that give structure and strength to connective tissues such as skin, tendons, and ligaments. A deficiency of lysine contributes to the short stature and osteoporosis seen in people with lysinuric protein intolerance. Other features of lysinuric protein intolerance are thought to result from abnormal protein transport (such as protein deposits in the lungs) or a lack of protein that can be used by the body (protein malnutrition).
lysinuric protein intolerance
Is lysinuric protein intolerance inherited ?
This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
lysinuric protein intolerance
What are the treatments for lysinuric protein intolerance ?
These resources address the diagnosis or management of lysinuric protein intolerance: - Gene Review: Gene Review: Lysinuric Protein Intolerance - Genetic Testing Registry: Lysinuric protein intolerance - MedlinePlus Encyclopedia: Aminoaciduria - MedlinePlus Encyclopedia: Malabsorption These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
lysinuric protein intolerance
What is (are) beta-ketothiolase deficiency ?
Beta-ketothiolase deficiency is an inherited disorder in which the body cannot effectively process a protein building block (amino acid) called isoleucine. This disorder also impairs the body's ability to process ketones, which are molecules produced during the breakdown of fats. The signs and symptoms of beta-ketothiolase deficiency typically appear between the ages of 6 months and 24 months. Affected children experience episodes of vomiting, dehydration, difficulty breathing, extreme tiredness (lethargy), and, occasionally, seizures. These episodes, which are called ketoacidotic attacks, sometimes lead to coma. Ketoacidotic attacks are frequently triggered by infections, periods without food (fasting), or increased intake of protein-rich foods.
beta-ketothiolase deficiency
How many people are affected by beta-ketothiolase deficiency ?
Beta-ketothiolase deficiency appears to be very rare. It is estimated to affect fewer than 1 in 1 million newborns.
beta-ketothiolase deficiency
What are the genetic changes related to beta-ketothiolase deficiency ?
Mutations in the ACAT1 gene cause beta-ketothiolase deficiency. This gene provides instructions for making an enzyme that is found in the energy-producing centers within cells (mitochondria). This enzyme plays an essential role in breaking down proteins and fats from the diet. Specifically, the ACAT1 enzyme helps process isoleucine, which is a building block of many proteins, and ketones, which are produced during the breakdown of fats. Mutations in the ACAT1 gene reduce or eliminate the activity of the ACAT1 enzyme. A shortage of this enzyme prevents the body from processing proteins and fats properly. As a result, related compounds can build up to toxic levels in the blood. These substances cause the blood to become too acidic (ketoacidosis), which can damage the body's tissues and organs, particularly in the nervous system.
beta-ketothiolase deficiency
Is beta-ketothiolase deficiency inherited ?
This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
beta-ketothiolase deficiency
What are the treatments for beta-ketothiolase deficiency ?
These resources address the diagnosis or management of beta-ketothiolase deficiency: - Baby's First Test - Genetic Testing Registry: Deficiency of acetyl-CoA acetyltransferase These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
beta-ketothiolase deficiency
What is (are) hypermanganesemia with dystonia, polycythemia, and cirrhosis ?
Hypermanganesemia with dystonia, polycythemia, and cirrhosis (HMDPC) is an inherited disorder in which excessive amounts of the element manganese accumulate in the body, particularly in the brain, liver, and blood (hypermanganesemia). Signs and symptoms of this condition can appear in childhood (early-onset), typically between ages 2 and 15, or in adulthood (adult-onset). Manganese accumulates in a region of the brain responsible for the coordination of movement, causing neurological problems that make controlling movement difficult. Most children with the early-onset form of HMDPC experience involuntary tensing of the muscles in the arms and legs (four-limb dystonia), which often leads to a characteristic high-stepping walk described as a "cock-walk gait." Other neurological symptoms in affected children include involuntary trembling (tremor), unusually slow movement (bradykinesia), and slurred speech (dysarthria). The adult-onset form of HMDPC is characterized by a pattern of movement abnormalities known as parkinsonism, which includes bradykinesia, tremor, muscle rigidity, and an inability to hold the body upright and balanced (postural instability). Affected individuals have an increased number of red blood cells (polycythemia) and low levels of iron stored in the body. Additional features of HMDPC can include an enlarged liver (hepatomegaly), scarring (fibrosis) in the liver, and irreversible liver disease (cirrhosis).
hypermanganesemia with dystonia, polycythemia, and cirrhosis
How many people are affected by hypermanganesemia with dystonia, polycythemia, and cirrhosis ?
The prevalence of HMDPC is unknown. A small number of cases have been described in the scientific literature.
hypermanganesemia with dystonia, polycythemia, and cirrhosis
What are the genetic changes related to hypermanganesemia with dystonia, polycythemia, and cirrhosis ?
Mutations in the SLC30A10 gene cause HMDPC. This gene provides instructions for making a protein that transports manganese across cell membranes. Manganese is important for many cellular functions, but large amounts are toxic, particularly to brain and liver cells. The SLC30A10 protein is found in the membranes surrounding liver cells and nerve cells in the brain, as well as in the membranes of structures within these cells. The protein protects these cells from high concentrations of manganese by removing manganese when levels become elevated. Mutations in the SLC30A10 gene impair the transport of manganese out of cells, allowing the element to build up in the brain and liver. Manganese accumulation in the brain leads to the movement problems characteristic of HMDPC. Damage from manganese buildup in the liver leads to liver abnormalities in people with this condition. High levels of manganese help increase the production of red blood cells, so excess amounts of this element also result in polycythemia.
hypermanganesemia with dystonia, polycythemia, and cirrhosis
Is hypermanganesemia with dystonia, polycythemia, and cirrhosis inherited ?
This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
hypermanganesemia with dystonia, polycythemia, and cirrhosis
What are the treatments for hypermanganesemia with dystonia, polycythemia, and cirrhosis ?
These resources address the diagnosis or management of HMDPC: - Gene Review: Gene Review: Dystonia/Parkinsonism, Hypermanganesemia, Polycythemia, and Chronic Liver Disease - Genetic Testing Registry: Hypermanganesemia with dystonia, polycythemia and cirrhosis These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
hypermanganesemia with dystonia, polycythemia, and cirrhosis
What is (are) 1q21.1 microdeletion ?
1q21.1 microdeletion is a chromosomal change in which a small piece of chromosome 1 is deleted in each cell. The deletion occurs on the long (q) arm of the chromosome in a region designated q21.1. This chromosomal change increases the risk of delayed development, intellectual disability, physical abnormalities, and neurological and psychiatric problems. However, some people with a 1q21.1 microdeletion do not appear to have any associated features. About 75 percent of all children with a 1q21.1 microdeletion have delayed development, particularly affecting the development of motor skills such as sitting, standing, and walking. The intellectual disability and learning problems associated with this genetic change are usually mild. Distinctive facial features can also be associated with 1q21.1 microdeletions. The changes are usually subtle and can include a prominent forehead; a large, rounded nasal tip; a long space between the nose and upper lip (philtrum); and a high, arched roof of the mouth (palate). Other common signs and symptoms of 1q21.1 microdeletions include an unusually small head (microcephaly), short stature, and eye problems such as clouding of the lenses (cataracts). Less frequently, 1q21.1 microdeletions are associated with heart defects, abnormalities of the genitalia or urinary system, bone abnormalities (particularly in the hands and feet), and hearing loss. Neurological problems that have been reported in people with a 1q21.1 microdeletion include seizures and weak muscle tone (hypotonia). Psychiatric or behavioral problems affect a small percentage of people with this genetic change. These include developmental conditions called autism spectrum disorders that affect communication and social interaction, attention deficit hyperactivity disorder (ADHD), and sleep disturbances. Studies suggest that deletions of genetic material from the 1q21.1 region may also be risk factors for schizophrenia. Some people with a 1q21.1 microdeletion do not have any of the intellectual, physical, or psychiatric features described above. In these individuals, the microdeletion is often detected when they undergo genetic testing because they have a relative with the chromosomal change. It is unknown why 1q21.1 microdeletions cause cognitive and physical changes in some individuals but few or no health problems in others, even within the same family.
1q21.1 microdeletion
How many people are affected by 1q21.1 microdeletion ?
1q21.1 microdeletion is a rare chromosomal change; only a few dozen individuals with this deletion have been reported in the medical literature.
1q21.1 microdeletion
What are the genetic changes related to 1q21.1 microdeletion ?
Most people with a 1q21.1 microdeletion are missing a sequence of about 1.35 million DNA building blocks (base pairs), also written as 1.35 megabases (Mb), in the q21.1 region of chromosome 1. However, the exact size of the deleted region varies. This deletion affects one of the two copies of chromosome 1 in each cell. The signs and symptoms that can result from a 1q21.1 microdeletion are probably related to the loss of several genes in this region. Researchers are working to determine which missing genes contribute to the specific features associated with the deletion. Because some people with a 1q21.1 microdeletion have no obvious related features, additional genetic or environmental factors are thought to be involved in the development of signs and symptoms. Researchers sometimes refer to 1q21.1 microdeletion as the recurrent distal 1.35-Mb deletion to distinguish it from the genetic change that causes thrombocytopenia-absent radius syndrome (TAR syndrome). TAR syndrome results from the deletion of a different, smaller DNA segment in the chromosome 1q21.1 region near the area where the 1.35-Mb deletion occurs. The chromosomal change related to TAR syndrome is often called the 200-kb deletion.
1q21.1 microdeletion
Is 1q21.1 microdeletion inherited ?
1q21.1 microdeletion is inherited in an autosomal dominant pattern, which means that missing genetic material from one of the two copies of chromosome 1 in each cell is sufficient to increase the risk of delayed development, intellectual disability, and other signs and symptoms. In at least half of cases, individuals with a 1q21.1 microdeletion inherit the chromosomal change from a parent. In general, parents who carry a 1q21.1 microdeletion have milder signs and symptoms than their children who inherit the deletion, even though the deletion is the same size. About one-quarter of these parents have no associated features. A 1q21.1 microdeletion can also occur in people whose parents do not carry the chromosomal change. In this situation, the deletion occurs most often as a random event during the formation of reproductive cells (eggs or sperm) in a parent or in early embryonic development.
1q21.1 microdeletion
What are the treatments for 1q21.1 microdeletion ?
These resources address the diagnosis or management of 1q21.1 microdeletion: - Gene Review: Gene Review: 1q21.1 Recurrent Microdeletion - Genetic Testing Registry: 1q21.1 recurrent microdeletion These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
1q21.1 microdeletion
What is (are) rapid-onset dystonia parkinsonism ?
Rapid-onset dystonia parkinsonism is a rare movement disorder. "Rapid-onset" refers to the abrupt appearance of signs and symptoms over a period of hours to days. Dystonia is a condition characterized by involuntary, sustained muscle contractions. Parkinsonism can include tremors, unusually slow movement (bradykinesia), rigidity, an inability to hold the body upright and balanced (postural instability), and a shuffling walk that can cause recurrent falls. Rapid-onset dystonia parkinsonism causes movement abnormalities that can make it difficult to walk, talk, and carry out other activities of daily life. In this disorder, dystonia affects the arms and legs, causing muscle cramping and spasms. Facial muscles are often affected, resulting in problems with speech and swallowing. The movement abnormalities associated with rapid-onset dystonia parkinsonism tend to begin near the top of the body and move downward, first affecting the facial muscles, then the arms, and finally the legs. The signs and symptoms of rapid-onset dystonia parkinsonism most commonly appear in adolescence or young adulthood. In some affected individuals, signs and symptoms can be triggered by an infection, physical stress (such as prolonged exercise), emotional stress, or alcohol consumption. The signs and symptoms tend to stabilize within about a month, but they typically do not improve much after that. In some people with this condition, the movement abnormalities abruptly worsen during a second episode several years later. Some people with rapid-onset dystonia parkinsonism have been diagnosed with anxiety, social phobias, depression, and seizures. It is unclear whether these disorders are related to the genetic changes that cause rapid-onset dystonia parkinsonism.
rapid-onset dystonia parkinsonism
How many people are affected by rapid-onset dystonia parkinsonism ?
Rapid-onset dystonia parkinsonism appears to be a rare disorder, although its prevalence is unknown. It has been diagnosed in individuals and families from the United States, Europe, and Korea.
rapid-onset dystonia parkinsonism
What are the genetic changes related to rapid-onset dystonia parkinsonism ?
Rapid-onset dystonia parkinsonism is caused by mutations in the ATP1A3 gene. This gene provides instructions for making one part of a larger protein called Na+/K+ ATPase, also known as the sodium pump. This protein is critical for the normal function of nerve cells (neurons) in the brain. It transports charged atoms (ions) into and out of neurons, which is an essential part of the signaling process that controls muscle movement. Mutations in the ATP1A3 gene reduce the activity of the Na+/K+ ATPase or make the protein unstable. Studies suggest that the defective protein is unable to transport ions normally, which disrupts the electrical activity of neurons in the brain. However, it is unclear how a malfunctioning Na+/K+ ATPase causes the movement abnormalities characteristic of rapid-onset dystonia parkinsonism. In some people with rapid-onset dystonia parkinsonism, no mutation in the ATP1A3 gene has been identified. The genetic cause of the disorder is unknown in these individuals. Researchers believe that mutations in at least one other gene, which has not been identified, can cause this disorder.
rapid-onset dystonia parkinsonism
Is rapid-onset dystonia parkinsonism inherited ?
This condition is inherited in an autosomal dominant pattern, which means one copy of the altered ATP1A3 gene in each cell is sufficient to cause the disorder. In most cases, an affected person inherits a mutation from one affected parent. Other cases result from new mutations in the gene and occur in people with no history of the disorder in their family. Not everyone who has an ATP1A3 mutation will ultimately develop the signs and symptoms of rapid-onset dystonia parkinsonism. It is unclear why some people with a gene mutation develop movement abnormalities and others do not.
rapid-onset dystonia parkinsonism
What are the treatments for rapid-onset dystonia parkinsonism ?
These resources address the diagnosis or management of rapid-onset dystonia parkinsonism: - Gene Review: Gene Review: Rapid-Onset Dystonia-Parkinsonism - Genetic Testing Registry: Dystonia 12 These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
rapid-onset dystonia parkinsonism
What is (are) glucose-galactose malabsorption ?
Glucose-galactose malabsorption is a condition in which the cells lining the intestine cannot take in the sugars glucose and galactose, which prevents proper digestion of these molecules and larger molecules made from them. Glucose and galactose are called simple sugars, or monosaccharides. Sucrose (table sugar) and lactose (the sugar found in milk) are called disaccharides because they are made from two simple sugars, and are broken down into these simple sugars during digestion. Sucrose is broken down into glucose and another simple sugar called fructose, and lactose is broken down into glucose and galactose. As a result, lactose, sucrose and other compounds made from sugar molecules (carbohydrates) cannot be digested by individuals with glucose-galactose malabsorption. Glucose-galactose malabsorption generally becomes apparent in the first few weeks of a baby's life. Affected infants experience severe diarrhea resulting in life-threatening dehydration, increased acidity of the blood and tissues (acidosis), and weight loss when fed breast milk or regular infant formulas. However, they are able to digest fructose-based formulas that do not contain glucose or galactose. Some affected children are better able to tolerate glucose and galactose as they get older. Small amounts of glucose in the urine (mild glucosuria) may occur intermittently in this disorder. Affected individuals may also develop kidney stones or more widespread deposits of calcium within the kidneys.
glucose-galactose malabsorption
How many people are affected by glucose-galactose malabsorption ?
Glucose-galactose malabsorption is a rare disorder; only a few hundred cases have been identified worldwide. However, as many as 10 percent of the population may have a somewhat reduced capacity for glucose absorption without associated health problems. This condition may be a milder variation of glucose-galactose malabsorption.
glucose-galactose malabsorption
What are the genetic changes related to glucose-galactose malabsorption ?
Mutations in the SLC5A1 gene cause glucose-galactose malabsorption. The SLC5A1 gene provides instructions for producing a sodium/glucose cotransporter protein called SGLT1. This protein is found mainly in the intestinal tract and, to a lesser extent, in the kidneys, where it is involved in transporting glucose and the structurally similar galactose across cell membranes. The sodium/glucose cotransporter protein is important in the functioning of intestinal epithelial cells, which are cells that line the walls of the intestine. These cells have fingerlike projections called microvilli that absorb nutrients from food as it passes through the intestine. Based on their appearance, groups of these microvilli are known collectively as the brush border. The sodium/glucose cotransporter protein is involved in the process of using energy to move glucose and galactose across the brush border membrane for absorption, a mechanism called active transport. Sodium and water are transported across the brush border along with the sugars in this process. Mutations that prevent the sodium/glucose cotransporter protein from performing this function result in a buildup of glucose and galactose in the intestinal tract. This failure of active transport prevents the glucose and galactose from being absorbed and providing nourishment to the body. In addition, the water that normally would have been transported across the brush border with the sugar instead remains in the intestinal tract to be expelled with the stool, resulting in dehydration of the body's tissues and severe diarrhea.
glucose-galactose malabsorption
Is glucose-galactose malabsorption inherited ?
This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. In some cases, individuals with one altered gene have reduced levels of glucose absorption capacity as measured in laboratory tests, but this has not generally been shown to have significant health effects.
glucose-galactose malabsorption
What are the treatments for glucose-galactose malabsorption ?
These resources address the diagnosis or management of glucose-galactose malabsorption: - Genetic Testing Registry: Congenital glucose-galactose malabsorption These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
glucose-galactose malabsorption
What is (are) mandibulofacial dysostosis with microcephaly ?
Mandibulofacial dysostosis with microcephaly (MFDM) is a disorder that causes abnormalities of the head and face. People with this disorder often have an unusually small head at birth, and the head does not grow at the same rate as the rest of the body, so it appears that the head is getting smaller as the body grows (progressive microcephaly). Affected individuals have developmental delay and intellectual disability that can range from mild to severe. Speech and language problems are also common in this disorder. Facial abnormalities that occur in MFDM include underdevelopment of the middle of the face and the cheekbones (midface and malar hypoplasia) and an unusually small lower jaw (mandibular hypoplasia, also called micrognathia). The external ears are small and abnormally shaped, and they may have skin growths in front of them called preauricular tags. There may also be abnormalities of the ear canal, the tiny bones in the ears (ossicles), or a part of the inner ear called the semicircular canals. These ear abnormalities lead to hearing loss in most affected individuals. Some people with MFDM have an opening in the roof of the mouth (cleft palate), which may also contribute to hearing loss by increasing the risk of ear infections. Affected individuals can also have a blockage of the nasal passages (choanal atresia) that can cause respiratory problems. Heart problems, abnormalities of the thumbs, and short stature are other features that can occur in MFDM. Some people with this disorder also have blockage of the esophagus (esophageal atresia). In esophageal atresia, the upper esophagus does not connect to the lower esophagus and stomach. Most babies born with esophageal atresia (EA) also have a tracheoesophageal fistula (TEF), in which the esophagus and the trachea are abnormally connected, allowing fluids from the esophagus to get into the airways and interfere with breathing. Esophageal atresia/tracheoesophageal fistula (EA/TEF) is a life-threatening condition; without treatment, it prevents normal feeding and can cause lung damage from repeated exposure to esophageal fluids.
mandibulofacial dysostosis with microcephaly
How many people are affected by mandibulofacial dysostosis with microcephaly ?
MFDM is a rare disorder; its exact prevalence is unknown. More than 60 affected individuals have been described in the medical literature.
mandibulofacial dysostosis with microcephaly
What are the genetic changes related to mandibulofacial dysostosis with microcephaly ?
MFDM is caused by mutations in the EFTUD2 gene. This gene provides instructions for making one part (subunit) of two complexes called the major and minor spliceosomes. Spliceosomes help process messenger RNA (mRNA), which is a chemical cousin of DNA that serves as a genetic blueprint for making proteins. The spliceosomes recognize and then remove regions called introns to help produce mature mRNA molecules. EFTUD2 gene mutations that cause MFDM result in the production of little or no functional enzyme from one copy of the gene in each cell. A shortage of this enzyme likely impairs mRNA processing. The relationship between these mutations and the specific symptoms of MFDM is not well understood.
mandibulofacial dysostosis with microcephaly
Is mandibulofacial dysostosis with microcephaly inherited ?
This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. Most cases result from new mutations in the gene and occur in people with no history of the disorder in their family. In other cases, an affected person inherits the mutation from a parent. The parent may be mildly affected or may be unaffected. Sometimes the parent has the gene mutation only in some or all of their sperm or egg cells, which is known as germline mosaicism. In these cases, the parent has no signs or symptoms of the condition.
mandibulofacial dysostosis with microcephaly
What are the treatments for mandibulofacial dysostosis with microcephaly ?
These resources address the diagnosis or management of MFDM: - Gene Review: Gene Review: Mandibulofacial Dysostosis with Microcephaly - Genetic Testing Registry: Growth and mental retardation, mandibulofacial dysostosis, microcephaly, and cleft palate These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
mandibulofacial dysostosis with microcephaly
What is (are) craniofacial microsomia ?
Craniofacial microsomia is a term used to describe a spectrum of abnormalities that primarily affect the development of the skull (cranium) and face before birth. Microsomia means abnormal smallness of body structures. Most people with craniofacial microsomia have differences in the size and shape of facial structures between the right and left sides of the face (facial asymmetry). In about two-thirds of cases, both sides of the face have abnormalities, which usually differ from one side to the other. Other individuals with craniofacial microsomia are affected on only one side of the face. The facial characteristics in craniofacial microsomia typically include underdevelopment of one side of the upper or lower jaw (maxillary or mandibular hypoplasia), which can cause dental problems and difficulties with feeding and speech. In cases of severe mandibular hypoplasia, breathing may also be affected. People with craniofacial microsomia usually have ear abnormalities affecting one or both ears, typically to different degrees. They may have growths of skin (skin tags) in front of the ear (preauricular tags), an underdeveloped or absent external ear (microtia or anotia), or a closed or absent ear canal; these abnormalities may lead to hearing loss. Eye problems are less common in craniofacial microsomia, but some affected individuals have an unusually small eyeball (microphthalmia) or other eye abnormalities that result in vision loss. Abnormalities in other parts of the body, such as malformed bones of the spine (vertebrae), abnormally shaped kidneys, and heart defects, may also occur in people with craniofacial microsomia. Many other terms have been used for craniofacial microsomia. These other names generally refer to forms of craniofacial microsomia with specific combinations of signs and symptoms, although sometimes they are used interchangeably. Hemifacial microsomia often refers to craniofacial microsomia with maxillary or mandibular hypoplasia. People with hemifacial microsomia and noncancerous (benign) growths in the eye called epibulbar dermoids may be said to have Goldenhar syndrome or oculoauricular dysplasia.
craniofacial microsomia
How many people are affected by craniofacial microsomia ?
Craniofacial microsomia has been estimated to occur in between 1 in 5,600 and 1 in 26,550 newborns. However, this range may be an underestimate because not all medical professionals agree on the criteria for diagnosis of this condition, and because mild cases may never come to medical attention. For reasons that are unclear, the disorder occurs about 50 percent more often in males than in females.
craniofacial microsomia
What are the genetic changes related to craniofacial microsomia ?
It is unclear what genes are involved in craniofacial microsomia. This condition results from problems in the development of structures in the embryo called the first and second pharyngeal arches (also called branchial or visceral arches). Tissue layers in the six pairs of pharyngeal arches give rise to the muscles, arteries, nerves, and cartilage of the face and neck. Specifically, the first and second pharyngeal arches develop into the lower jaw, the nerves and muscles used for chewing and facial expression, the external ear, and the bones of the middle ear. Interference with the normal development of these structures can result in the abnormalities characteristic of craniofacial microsomia. There are several factors that can disrupt the normal development of the first and second pharyngeal arches and lead to craniofacial microsomia. Some individuals with this condition have chromosomal abnormalities such as deletions or duplications of genetic material; these individuals often have additional developmental problems or malformations. Occasionally, craniofacial microsomia occurs in multiple members of a family in a pattern that suggests inheritance of a causative gene mutation, but the gene or genes involved are unknown. In other families, individuals seem to inherit a predisposition to the disorder. The risk of craniofacial microsomia can also be increased by environmental factors, such as certain drugs taken by the mother during pregnancy. In most affected individuals, the cause of the disorder is unknown. It is not well understood why certain disruptions to development affect the first and second pharyngeal arches in particular. Researchers suggest that these structures may develop together in such a way that they respond as a unit to these disruptions.
craniofacial microsomia
Is craniofacial microsomia inherited ?
Craniofacial microsomia most often occurs in a single individual in a family and is not inherited. If the condition is caused by a chromosomal abnormality, it may be inherited from one affected parent or it may result from a new abnormality in the chromosome and occur in people with no history of the disorder in their family. In 1 to 2 percent of cases, craniofacial microsomia is inherited in an autosomal dominant pattern, which means one copy of an altered gene in each cell is sufficient to cause the disorder. In rare cases, the condition is inherited in an autosomal recessive pattern, which means both copies of a gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The gene or genes involved in craniofacial microsomia are unknown. In some affected families, people seem to inherit an increased risk of developing craniofacial microsomia, not the condition itself. In these cases, some combination of genetic changes and environmental factors may be involved.
craniofacial microsomia
What are the treatments for craniofacial microsomia ?
These resources address the diagnosis or management of craniofacial microsomia: - Children's Hospital and Medical Center of the University of Nebraska - Gene Review: Gene Review: Craniofacial Microsomia Overview - Genetic Testing Registry: Goldenhar syndrome - Seattle Children's Hospital - Virginia Commonwealth University These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
craniofacial microsomia
What is (are) branchio-oculo-facial syndrome ?
Branchio-oculo-facial syndrome is a condition that affects development before birth, particularly of structures in the face and neck. Its characteristic features include skin anomalies on the neck, malformations of the eyes and ears, and distinctive facial features. "Branchio-" refers to the branchial arches, which are structures in the developing embryo that give rise to tissues in the face and neck. In people with branchio-oculo-facial syndrome, the first and second branchial arches do not develop properly, leading to abnormal patches of skin, typically on the neck or near the ears. These patches can be unusually thin, hairy, or red and densely packed with blood vessels (hemangiomatous). In a small number of individuals, tissue from a gland called the thymus is abnormally located on the skin of the neck (dermal thymus). Problems with branchial arch development underlie many of the other features of branchio-oculo-facial syndrome. "Oculo-" refers to the eyes. Many people with branchio-oculo-facial syndrome have malformations of the eyes that can lead to vision impairment. These abnormalities include unusually small eyeballs (microphthalmia), no eyeballs (anophthalmia), a gap or split in structures that make up the eyes (coloboma), or blockage of the tear ducts (nasolacrimal duct stenosis). Problems with development of the face lead to distinctive facial features in people with branchio-oculo-facial syndrome. Many affected individuals have a split in the upper lip (cleft lip) or a pointed upper lip that resembles a poorly repaired cleft lip (often called a pseudocleft lip) with or without an opening in the roof of the mouth (cleft palate). Other facial characteristics include widely spaced eyes (hypertelorism), an increased distance between the inner corners of the eyes (telecanthus), outside corners of the eyes that point upward (upslanting palpebral fissures), a broad nose with a flattened tip, and weakness of the muscles in the lower face. The ears are also commonly affected, resulting in malformed or prominent ears. Abnormalities of the inner ear or of the tiny bones in the ears (ossicles) can cause hearing loss in people with this condition. Branchio-oculo-facial syndrome can affect other structures and tissues as well. Some affected individuals have kidney abnormalities, such as malformed kidneys or multiple kidney cysts. Nail and teeth abnormalities also occur, and some people with this condition have prematurely graying hair.
branchio-oculo-facial syndrome
How many people are affected by branchio-oculo-facial syndrome ?
Branchio-oculo-facial syndrome is a rare condition, although the prevalence is unknown.
branchio-oculo-facial syndrome
What are the genetic changes related to branchio-oculo-facial syndrome ?
Branchio-oculo-facial syndrome is caused by mutations in the TFAP2A gene. This gene provides instructions for making a protein called transcription factor AP-2 alpha (AP-2). As its name suggests, this protein is a transcription factor, which means it attaches (binds) to specific regions of DNA and helps control the activity of particular genes. Transcription factor AP-2 regulates genes that are involved in several cellular processes, such as cell division and the self-destruction of cells that are no longer needed (apoptosis). This protein is critical during development before birth, particularly of the branchial arches, which form the structures of the face and neck. Most TFAP2A gene mutations that cause branchio-oculo-facial syndrome change single protein building blocks (amino acids) in the transcription factor AP-2 protein. These changes tend to occur in a region of the protein that allows it to bind to DNA. Without this function, transcription factor AP-2 cannot control the activity of genes during development, which disrupts the development of the eyes, ears, and face and causes the features of branchio-oculo-facial syndrome.
branchio-oculo-facial syndrome
Is branchio-oculo-facial syndrome inherited ?
Branchio-oculo-facial syndrome is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In about half of cases, an affected person inherits the mutation from one affected parent. The remaining cases occur in people whose parents do not have a mutation in the TFAP2A gene. In these situations, the mutation likely occurs as a random event during the formation of reproductive cells (eggs and sperm) in a parent or in early fetal development of the affected individual.
branchio-oculo-facial syndrome
What are the treatments for branchio-oculo-facial syndrome ?
These resources address the diagnosis or management of branchio-oculo-facial syndrome: - Gene Review: Gene Review: Branchiooculofacial Syndrome - Genetic Testing Registry: Branchiooculofacial syndrome - MedlinePlus Encyclopedia: Cleft Lip and Palate These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
branchio-oculo-facial syndrome
What is (are) tumor necrosis factor receptor-associated periodic syndrome ?
Tumor necrosis factor receptor-associated periodic syndrome (commonly known as TRAPS) is a condition characterized by recurrent episodes of fever. These fevers typically last about 3 weeks but can last from a few days to a few months. The frequency of the episodes varies greatly among affected individuals; fevers can occur anywhere between every 6 weeks to every few years. Some individuals can go many years without having a fever episode. Fever episodes usually occur spontaneously, but sometimes they can be brought on by a variety of triggers, such as minor injury, infection, stress, exercise, or hormonal changes. During episodes of fever, people with TRAPS can have additional signs and symptoms. These include abdominal and muscle pain and a spreading skin rash, typically found on the limbs. Affected individuals may also experience puffiness or swelling in the skin around the eyes (periorbital edema); joint pain; and inflammation in various areas of the body including the eyes, heart muscle, certain joints, throat, or mucous membranes such as the moist lining of the mouth and digestive tract. Occasionally, people with TRAPS develop amyloidosis, an abnormal buildup of a protein called amyloid in the kidneys that can lead to kidney failure. It is estimated that 15 to 20 percent of people with TRAPS develop amyloidosis, typically in mid-adulthood. The fever episodes characteristic of TRAPS can begin at any age, from infancy to late adulthood, but most people have their first episode in childhood.
tumor necrosis factor receptor-associated periodic syndrome
How many people are affected by tumor necrosis factor receptor-associated periodic syndrome ?
TRAPS has an estimated prevalence of one per million individuals; it is the second most common inherited recurrent fever syndrome, following a similar condition called familial Mediterranean fever. More than 1,000 people worldwide have been diagnosed with TRAPS.
tumor necrosis factor receptor-associated periodic syndrome
What are the genetic changes related to tumor necrosis factor receptor-associated periodic syndrome ?
TRAPS is caused by mutations in the TNFRSF1A gene. This gene provides instructions for making a protein called tumor necrosis factor receptor 1 (TNFR1). This protein is found within the membrane of cells, where it attaches (binds) to another protein called tumor necrosis factor (TNF). This binding sends signals that can trigger the cell either to initiate inflammation or to self-destruct. Signaling within the cell initiates a pathway that turns on a protein called nuclear factor kappa B that triggers inflammation and leads to the production of immune system proteins called cytokines. The self-destruction of the cell (apoptosis) is initiated when the TNFR1 protein, bound to the TNF protein, is brought into the cell and triggers a process known as the caspase cascade. Most TNFRSF1A gene mutations that cause TRAPS result in a TNFR1 protein that is folded into an incorrect 3-dimensional shape. These misfolded proteins are trapped within the cell and are not able to get to the cell surface to interact with TNF. Inside the cell, these proteins clump together and are thought to trigger alternative pathways that initiate inflammation. The clumps of protein constantly activate these alternative inflammation pathways, leading to excess inflammation in people with TRAPS. Additionally, because only one copy of the TNFRSF1A gene has a mutation, some normal TNFR1 proteins are produced and can bind to the TNF protein, leading to additional inflammation. It is unclear if disruption of the apoptosis pathway plays a role in the signs and symptoms of TRAPS.
tumor necrosis factor receptor-associated periodic syndrome
Is tumor necrosis factor receptor-associated periodic syndrome inherited ?
This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. However, some people who inherit the altered gene never develop features of TRAPS. (This situation is known as reduced penetrance.) It is unclear why some people with a mutated gene develop the disease and other people with the mutated gene do not. In most cases, an affected person inherits the mutation from one affected parent. Other cases result from new mutations in the gene and occur in people with no history of the disorder in their family.
tumor necrosis factor receptor-associated periodic syndrome
What are the treatments for tumor necrosis factor receptor-associated periodic syndrome ?
These resources address the diagnosis or management of TRAPS: - Genetic Testing Registry: TNF receptor-associated periodic fever syndrome (TRAPS) - University College London: National Amyloidosis Center (UK) These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
tumor necrosis factor receptor-associated periodic syndrome
What is (are) deafness and myopia syndrome ?
Deafness and myopia syndrome is a disorder that causes problems with both hearing and vision. People with this disorder have moderate to profound hearing loss in both ears that may worsen over time. The hearing loss may be described as sensorineural, meaning that it is related to changes in the inner ear, or it may be caused by auditory neuropathy, which is a problem with the transmission of sound (auditory) signals from the inner ear to the brain. The hearing loss is either present at birth (congenital) or begins in infancy, before the child learns to speak (prelingual). Affected individuals also have severe nearsightedness (high myopia). These individuals are able to see nearby objects clearly, but objects that are farther away appear blurry. The myopia is usually diagnosed by early childhood.
deafness and myopia syndrome
How many people are affected by deafness and myopia syndrome ?
The prevalence of deafness and myopia syndrome is unknown. Only a few affected families have been described in the medical literature.
deafness and myopia syndrome
What are the genetic changes related to deafness and myopia syndrome ?
Deafness and myopia syndrome is caused by mutations in the SLITRK6 gene. The protein produced from this gene is found primarily in the inner ear and the eye. This protein promotes growth and survival of nerve cells (neurons) in the inner ear that transmit auditory signals. It also controls (regulates) the growth of the eye after birth. In particular, the SLITRK6 protein influences the length of the eyeball (axial length), which affects whether a person will be nearsighted or farsighted, or will have normal vision. The SLITRK6 protein spans the cell membrane, where it is anchored in the proper position to perform its function. SLITRK6 gene mutations that cause deafness and myopia syndrome result in an abnormally short SLITRK6 protein that is not anchored properly to the cell membrane. As a result, the protein is unable to function normally. Impaired SLITRK6 protein function leads to abnormal nerve development in the inner ear and improperly controlled eyeball growth, resulting in the hearing loss and nearsightedness that occur in deafness and myopia syndrome.
deafness and myopia syndrome
Is deafness and myopia syndrome inherited ?
This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
deafness and myopia syndrome
What are the treatments for deafness and myopia syndrome ?
These resources address the diagnosis or management of deafness and myopia syndrome: - Baby's First Test: Hearing Loss - EyeSmart: Eyeglasses for Vision Correction - Gene Review: Gene Review: Deafness and Myopia Syndrome - Harvard Medical School Center for Hereditary Deafness - KidsHealth: Hearing Evaluation in Children - MedlinePlus Encyclopedia: Cochlear Implant - MedlinePlus Health Topic: Cochlear Implants - MedlinePlus Health Topic: Hearing Aids - MedlinePlus Health Topic: Newborn Screening These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
deafness and myopia syndrome
What is (are) hyperkalemic periodic paralysis ?
Hyperkalemic periodic paralysis is a condition that causes episodes of extreme muscle weakness or paralysis, usually beginning in infancy or early childhood. Most often, these episodes involve a temporary inability to move muscles in the arms and legs. Episodes tend to increase in frequency until mid-adulthood, after which they occur less frequently. Factors that can trigger attacks include rest after exercise, potassium-rich foods such as bananas and potatoes, stress, fatigue, alcohol, pregnancy, exposure to cold temperatures, certain medications, and periods without food (fasting). Muscle strength usually returns to normal between attacks, although many affected people continue to experience mild stiffness (myotonia), particularly in muscles of the face and hands. Most people with hyperkalemic periodic paralysis have increased levels of potassium in their blood (hyperkalemia) during attacks. Hyperkalemia results when the weak or paralyzed muscles release potassium ions into the bloodstream. In other cases, attacks are associated with normal blood potassium levels (normokalemia). Ingesting potassium can trigger attacks in affected individuals, even if blood potassium levels do not go up.
hyperkalemic periodic paralysis
How many people are affected by hyperkalemic periodic paralysis ?
Hyperkalemic periodic paralysis affects an estimated 1 in 200,000 people.
hyperkalemic periodic paralysis
What are the genetic changes related to hyperkalemic periodic paralysis ?
Mutations in the SCN4A gene can cause hyperkalemic periodic paralysis. The SCN4A gene provides instructions for making a protein that plays an essential role in muscles used for movement (skeletal muscles). For the body to move normally, these muscles must tense (contract) and relax in a coordinated way. One of the changes that helps trigger muscle contractions is the flow of positively charged atoms (ions), including sodium, into muscle cells. The SCN4A protein forms channels that control the flow of sodium ions into these cells. Mutations in the SCN4A gene alter the usual structure and function of sodium channels. The altered channels stay open too long or do not stay closed long enough, allowing more sodium ions to flow into muscle cells. This increase in sodium ions triggers the release of potassium from muscle cells, which causes more sodium channels to open and stimulates the flow of even more sodium ions into these cells. These changes in ion transport reduce the ability of skeletal muscles to contract, leading to episodes of muscle weakness or paralysis. In 30 to 40 percent of cases, the cause of hyperkalemic periodic paralysis is unknown. Changes in other genes, which have not been identified, likely cause the disorder in these cases.
hyperkalemic periodic paralysis
Is hyperkalemic periodic paralysis inherited ?
This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder.
hyperkalemic periodic paralysis
What are the treatments for hyperkalemic periodic paralysis ?
These resources address the diagnosis or management of hyperkalemic periodic paralysis: - Gene Review: Gene Review: Hyperkalemic Periodic Paralysis - Genetic Testing Registry: Familial hyperkalemic periodic paralysis - Genetic Testing Registry: Hyperkalemic Periodic Paralysis Type 1 - MedlinePlus Encyclopedia: Hyperkalemic Periodic Paralysis - Periodic Paralysis International: How is Periodic Paralysis Diagnosed? These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
hyperkalemic periodic paralysis
What is (are) Meesmann corneal dystrophy ?
Meesmann corneal dystrophy is an eye disease that affects the cornea, which is the clear front covering of the eye. This condition is characterized by the formation of tiny round cysts in the outermost layer of the cornea, called the corneal epithelium. This part of the cornea acts as a barrier to help prevent foreign materials, such as dust and bacteria, from entering the eye. In people with Meesmann corneal dystrophy, cysts can appear as early as the first year of life. They usually affect both eyes and increase in number over time. The cysts usually do not cause any symptoms until late adolescence or adulthood, when they start to break open (rupture) on the surface of the cornea and cause irritation. The resulting symptoms typically include increased sensitivity to light (photophobia), twitching of the eyelids (blepharospasm), increased tear production, the sensation of having a foreign object in the eye, and an inability to tolerate wearing contact lenses. Some affected individuals also have temporary episodes of blurred vision.
Meesmann corneal dystrophy
How many people are affected by Meesmann corneal dystrophy ?
Meesmann corneal dystrophy is a rare disorder whose prevalence is unknown. It was first described in a large, multi-generational German family with more than 100 affected members. Since then, the condition has been reported in individuals and families worldwide.
Meesmann corneal dystrophy
What are the genetic changes related to Meesmann corneal dystrophy ?
Meesmann corneal dystrophy can result from mutations in either the KRT12 gene or the KRT3 gene. These genes provide instructions for making proteins called keratin 12 and keratin 3, which are found in the corneal epithelium. The two proteins interact to form the structural framework of this layer of the cornea. Mutations in either the KRT12 or KRT3 gene weaken this framework, causing the corneal epithelium to become fragile and to develop the cysts that characterize the disorder. The cysts likely contain clumps of abnormal keratin proteins and other cellular debris. When the cysts rupture, they cause eye irritation and the other symptoms of Meesmann corneal dystrophy.
Meesmann corneal dystrophy
Is Meesmann corneal dystrophy inherited ?
This condition is inherited in an autosomal dominant pattern, which means one copy of an altered KRT12 or KRT3 gene in each cell is sufficient to cause the disorder. In most cases, an affected person inherits the condition from an affected parent.
Meesmann corneal dystrophy
What are the treatments for Meesmann corneal dystrophy ?
These resources address the diagnosis or management of Meesmann corneal dystrophy: - Genetic Testing Registry: Meesman's corneal dystrophy - Merck Manual Home Health Handbook: Tests for Eye Disorders: The Eye Examination These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
Meesmann corneal dystrophy
What is (are) achondroplasia ?
Achondroplasia is a form of short-limbed dwarfism. The word achondroplasia literally means "without cartilage formation." Cartilage is a tough but flexible tissue that makes up much of the skeleton during early development. However, in achondroplasia the problem is not in forming cartilage but in converting it to bone (a process called ossification), particularly in the long bones of the arms and legs. Achondroplasia is similar to another skeletal disorder called hypochondroplasia, but the features of achondroplasia tend to be more severe. All people with achondroplasia have short stature. The average height of an adult male with achondroplasia is 131 centimeters (4 feet, 4 inches), and the average height for adult females is 124 centimeters (4 feet, 1 inch). Characteristic features of achondroplasia include an average-size trunk, short arms and legs with particularly short upper arms and thighs, limited range of motion at the elbows, and an enlarged head (macrocephaly) with a prominent forehead. Fingers are typically short and the ring finger and middle finger may diverge, giving the hand a three-pronged (trident) appearance. People with achondroplasia are generally of normal intelligence. Health problems commonly associated with achondroplasia include episodes in which breathing slows or stops for short periods (apnea), obesity, and recurrent ear infections. In childhood, individuals with the condition usually develop a pronounced and permanent sway of the lower back (lordosis) and bowed legs. Some affected people also develop abnormal front-to-back curvature of the spine (kyphosis) and back pain. A potentially serious complication of achondroplasia is spinal stenosis, which is a narrowing of the spinal canal that can pinch (compress) the upper part of the spinal cord. Spinal stenosis is associated with pain, tingling, and weakness in the legs that can cause difficulty with walking. Another uncommon but serious complication of achondroplasia is hydrocephalus, which is a buildup of fluid in the brain in affected children that can lead to increased head size and related brain abnormalities.
achondroplasia
How many people are affected by achondroplasia ?
Achondroplasia is the most common type of short-limbed dwarfism. The condition occurs in 1 in 15,000 to 40,000 newborns.
achondroplasia
What are the genetic changes related to achondroplasia ?
Mutations in the FGFR3 gene cause achondroplasia. The FGFR3 gene provides instructions for making a protein that is involved in the development and maintenance of bone and brain tissue. Two specific mutations in the FGFR3 gene are responsible for almost all cases of achondroplasia. Researchers believe that these mutations cause the FGFR3 protein to be overly active, which interferes with skeletal development and leads to the disturbances in bone growth seen with this disorder.
achondroplasia
Is achondroplasia inherited ?
Achondroplasia is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. About 80 percent of people with achondroplasia have average-size parents; these cases result from new mutations in the FGFR3 gene. In the remaining cases, people with achondroplasia have inherited an altered FGFR3 gene from one or two affected parents. Individuals who inherit two altered copies of this gene typically have a severe form of achondroplasia that causes extreme shortening of the bones and an underdeveloped rib cage. These individuals are usually stillborn or die shortly after birth from respiratory failure.
achondroplasia
What are the treatments for achondroplasia ?
These resources address the diagnosis or management of achondroplasia: - Gene Review: Gene Review: Achondroplasia - GeneFacts: Achondroplasia: Diagnosis - GeneFacts: Achondroplasia: Management - Genetic Testing Registry: Achondroplasia - MedlinePlus Encyclopedia: Achondroplasia - MedlinePlus Encyclopedia: Hydrocephalus - MedlinePlus Encyclopedia: Lordosis - MedlinePlus Encyclopedia: Spinal Stenosis These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
achondroplasia