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What is (are) hypomagnesemia with secondary hypocalcemia ?
Hypomagnesemia with secondary hypocalcemia is an inherited condition caused by the body's inability to absorb and retain magnesium that is taken in through the diet. As a result, magnesium levels in the blood are severely low (hypomagnesemia). Hypomagnesemia impairs the function of the parathyroid glands, which are small hormone-producing glands located in the neck. Normally, the parathyroid glands release a hormone that increases blood calcium levels when they are low. Magnesium is required for the production and release of parathyroid hormone, so when magnesium is too low, insufficient parathyroid hormone is produced and blood calcium levels are also reduced (hypocalcemia). The hypocalcemia is described as "secondary" because it occurs as a consequence of hypomagnesemia. Shortages of magnesium and calcium can cause neurological problems that begin in infancy, including painful muscle spasms (tetany) and seizures. If left untreated, hypomagnesemia with secondary hypocalcemia can lead to developmental delay, intellectual disability, a failure to gain weight and grow at the expected rate (failure to thrive), and heart failure.
hypomagnesemia with secondary hypocalcemia
How many people are affected by hypomagnesemia with secondary hypocalcemia ?
Hypomagnesemia with secondary hypocalcemia is thought to be a rare condition, but its prevalence is unknown.
hypomagnesemia with secondary hypocalcemia
What are the genetic changes related to hypomagnesemia with secondary hypocalcemia ?
Hypomagnesemia with secondary hypocalcemia is caused by mutations in the TRPM6 gene. This gene provides instructions for making a protein that acts as a channel, which allows charged atoms (ions) of magnesium (Mg2+) to flow into cells; the channel may also allow small amounts of calcium ions (Ca2+) to pass into cells. Magnesium is involved in many cell processes, including production of cellular energy, maintenance of DNA building blocks (nucleotides), protein production, and cell growth and death. Magnesium and calcium are also required for the normal functioning of nerve cells that control muscle movement (motor neurons). The TRPM6 channel is embedded in the membrane of epithelial cells that line the large intestine, structures in the kidneys known as distal convoluted tubules, the lungs, and the testes in males. When the body needs additional Mg2+, the TRPM6 channel allows it to be absorbed in the intestine and filtered from the fluids that pass through the kidneys by the distal convoluted tubules. When the body has sufficient or too much Mg2+, the TRPM6 channel does not filter out the Mg2+ from fluids but allows the ion to be released from the kidney cells into the urine. The channel also helps to regulate Ca2+, but to a lesser degree. Most TRPM6 gene mutations that cause hypomagnesemia with secondary hypocalcemia result in a lack of functional protein. A loss of functional TRPM6 channels prevent Mg2+ absorption in the intestine and cause excessive amounts of Mg2+ to be excreted by the kidneys and released in the urine. A lack of Mg2+ in the body impairs the production of parathyroid hormone, which likely reduces blood Ca2+ levels. Additionally, hypomagnesemia and hypocalcemia can disrupt many cell processes and impair the function of motor neurons, leading to neurological problems and movement disorders. If the condition is not effectively treated and low Mg2+ levels persist, signs and symptoms can worsen over time and may lead to early death.
hypomagnesemia with secondary hypocalcemia
Is hypomagnesemia with secondary hypocalcemia 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.
hypomagnesemia with secondary hypocalcemia
What are the treatments for hypomagnesemia with secondary hypocalcemia ?
These resources address the diagnosis or management of hypomagnesemia with secondary hypocalcemia: - Genetic Testing Registry: Hypomagnesemia 1, intestinal - MedlinePlus Encyclopedia: Hypomagnesemia 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
hypomagnesemia with secondary hypocalcemia
What is (are) X-linked adrenoleukodystrophy ?
X-linked adrenoleukodystrophy is a genetic disorder that occurs primarily in males. It mainly affects the nervous system and the adrenal glands, which are small glands located on top of each kidney. In this disorder, the fatty covering (myelin) that insulates nerves in the brain and spinal cord is prone to deterioration (demyelination), which reduces the ability of the nerves to relay information to the brain. In addition, damage to the outer layer of the adrenal glands (adrenal cortex) causes a shortage of certain hormones (adrenocortical insufficiency). Adrenocortical insufficiency may cause weakness, weight loss, skin changes, vomiting, and coma. There are three distinct types of X-linked adrenoleukodystrophy: a childhood cerebral form, an adrenomyeloneuropathy type, and a form called Addison disease only. Children with the cerebral form of X-linked adrenoleukodystrophy experience learning and behavioral problems that usually begin between the ages of 4 and 10. Over time the symptoms worsen, and these children may have difficulty reading, writing, understanding speech, and comprehending written material. Additional signs and symptoms of the cerebral form include aggressive behavior, vision problems, difficulty swallowing, poor coordination, and impaired adrenal gland function. The rate at which this disorder progresses is variable but can be extremely rapid, often leading to total disability within a few years. The life expectancy of individuals with this type depends on the severity of the signs and symptoms and how quickly the disorder progresses. Individuals with the cerebral form of X-linked adrenoleukodystrophy usually survive only a few years after symptoms begin but may survive longer with intensive medical support. Signs and symptoms of the adrenomyeloneuropathy type appear between early adulthood and middle age. Affected individuals develop progressive stiffness and weakness in their legs (paraparesis), experience urinary and genital tract disorders, and often show changes in behavior and thinking ability. Most people with the adrenomyeloneuropathy type also have adrenocortical insufficiency. In some severely affected individuals, damage to the brain and nervous system can lead to early death. People with X-linked adrenoleukodystrophy whose only symptom is adrenocortical insufficiency are said to have the Addison disease only form. In these individuals, adrenocortical insufficiency can begin anytime between childhood and adulthood. However, most affected individuals develop the additional features of the adrenomyeloneuropathy type by the time they reach middle age. The life expectancy of individuals with this form depends on the severity of the signs and symptoms, but typically this is the mildest of the three types. Rarely, individuals with X-linked adrenoleukodystrophy develop multiple features of the disorder in adolescence or early adulthood. In addition to adrenocortical insufficiency, these individuals usually have psychiatric disorders and a loss of intellectual function (dementia). It is unclear whether these individuals have a distinct form of the condition or a variation of one of the previously described types. For reasons that are unclear, different forms of X-linked adrenoleukodystrophy can be seen in affected individuals within the same family.
X-linked adrenoleukodystrophy
How many people are affected by X-linked adrenoleukodystrophy ?
The prevalence of X-linked adrenoleukodystrophy is 1 in 20,000 to 50,000 individuals worldwide. This condition occurs with a similar frequency in all populations.
X-linked adrenoleukodystrophy
What are the genetic changes related to X-linked adrenoleukodystrophy ?
Mutations in the ABCD1 gene cause X-linked adrenoleukodystrophy. The ABCD1 gene provides instructions for producing the adrenoleukodystrophy protein (ALDP), which is involved in transporting certain fat molecules called very long-chain fatty acids (VLCFAs) into peroxisomes. Peroxisomes are small sacs within cells that process many types of molecules, including VLCFAs. ABCD1 gene mutations result in a shortage (deficiency) of ALDP. When this protein is lacking, the transport and subsequent breakdown of VLCFAs is disrupted, causing abnormally high levels of these fats in the body. The accumulation of VLCFAs may be toxic to the adrenal cortex and myelin. Research suggests that the accumulation of VLCFAs triggers an inflammatory response in the brain, which could lead to the breakdown of myelin. The destruction of these tissues leads to the signs and symptoms of X-linked adrenoleukodystrophy.
X-linked adrenoleukodystrophy
Is X-linked adrenoleukodystrophy inherited ?
X-linked adrenoleukodystrophy is inherited in an X-linked pattern. 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 in each cell. In males (who have only one X chromosome), one altered copy of the ABCD1 gene in each cell is sufficient to cause X-linked adrenoleukodystrophy. Because females have two copies of the X chromosome, one altered copy of the ABCD1 gene in each cell usually does not cause any features of X-linked adrenoleukodystrophy; however, some females with one altered copy of the gene have health problems associated with this disorder. The signs and symptoms of X-linked adrenoleukodystrophy tend to appear at a later age in females than in males. Affected women usually develop features of the adrenomyeloneuropathy type.
X-linked adrenoleukodystrophy
What are the treatments for X-linked adrenoleukodystrophy ?
These resources address the diagnosis or management of X-linked adrenoleukodystrophy: - Gene Review: Gene Review: X-Linked Adrenoleukodystrophy - Genetic Testing Registry: Adrenoleukodystrophy - Genomics Education Programme (UK) - MedlinePlus Encyclopedia: Adrenoleukodystrophy - National Marrow Donor Program - X-linked Adrenoleukodystrophy Database: Diagnosis of X-ALD 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
X-linked adrenoleukodystrophy
What is (are) glycogen storage disease type 0 ?
Glycogen storage disease type 0 (also known as GSD 0) is a condition caused by the body's inability to form a complex sugar called glycogen, which is a major source of stored energy in the body. GSD 0 has two types: in muscle GSD 0, glycogen formation in the muscles is impaired, and in liver GSD 0, glycogen formation in the liver is impaired. The signs and symptoms of muscle GSD 0 typically begin in early childhood. Affected individuals often experience muscle pain and weakness or episodes of fainting (syncope) following moderate physical activity, such as walking up stairs. The loss of consciousness that occurs with fainting typically lasts up to several hours. Some individuals with muscle GSD 0 have a disruption of the heart's normal rhythm (arrhythmia) known as long QT syndrome. In all affected individuals, muscle GSD 0 impairs the heart's ability to effectively pump blood and increases the risk of cardiac arrest and sudden death, particularly after physical activity. Sudden death from cardiac arrest can occur in childhood or adolescence in people with muscle GSD 0. Individuals with liver GSD 0 usually show signs and symptoms of the disorder in infancy. People with this disorder develop low blood sugar (hypoglycemia) after going long periods of time without food (fasting). Signs of hypoglycemia become apparent when affected infants begin sleeping through the night and stop late-night feedings; these infants exhibit extreme tiredness (lethargy), pale skin (pallor), and nausea. During episodes of fasting, ketone levels in the blood may increase (ketosis). Ketones are molecules produced during the breakdown of fats, which occurs when stored sugars (such as glycogen) are unavailable. These short-term signs and symptoms of liver GSD 0 often improve when food is eaten and sugar levels in the body return to normal. The features of liver GSD 0 vary; they can be mild and go unnoticed for years, or they can include developmental delay and growth failure.
glycogen storage disease type 0
How many people are affected by glycogen storage disease type 0 ?
The prevalence of GSD 0 is unknown; fewer than 10 people with the muscle type and fewer than 30 people with the liver type have been described in the scientific literature. Because some people with muscle GSD 0 die from sudden cardiac arrest early in life before a diagnosis is made and many with liver GSD 0 have mild signs and symptoms, it is thought that GSD 0 may be underdiagnosed.
glycogen storage disease type 0
What are the genetic changes related to glycogen storage disease type 0 ?
Mutations in the GYS1 gene cause muscle GSD 0, and mutations in the GYS2 gene cause liver GSD 0. These genes provide instructions for making different versions of an enzyme called glycogen synthase. Both versions of glycogen synthase have the same function, to form glycogen molecules by linking together molecules of the simple sugar glucose, although they perform this function in different regions of the body. The GYS1 gene provides instructions for making muscle glycogen synthase; this form of the enzyme is produced in most cells, but it is especially abundant in heart (cardiac) muscle and the muscles used for movement (skeletal muscles). During cardiac muscle contractions or rapid or sustained movement of skeletal muscle, glycogen stored in muscle cells is broken down to supply the cells with energy. The GYS2 gene provides instructions for making liver glycogen synthase, which is produced solely in liver cells. Glycogen that is stored in the liver can be broken down rapidly when glucose is needed to maintain normal blood sugar levels between meals. Mutations in the GYS1 or GYS2 gene lead to a lack of functional glycogen synthase, which prevents the production of glycogen from glucose. Mutations that cause GSD 0 result in a complete absence of glycogen in either liver or muscle cells. As a result, these cells do not have glycogen as a source of stored energy to draw upon following physical activity or fasting. This shortage of glycogen leads to the signs and symptoms of GSD 0.
glycogen storage disease type 0
Is glycogen storage disease type 0 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.
glycogen storage disease type 0
What are the treatments for glycogen storage disease type 0 ?
These resources address the diagnosis or management of glycogen storage disease type 0: - Genetic Testing Registry: Glycogen storage disease 0, muscle - Genetic Testing Registry: Hypoglycemia with deficiency of glycogen synthetase in the liver 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
glycogen storage disease type 0
What is (are) mucopolysaccharidosis type II ?
Mucopolysaccharidosis type II (MPS II), also known as Hunter syndrome, is a condition that affects many different parts of the body and occurs almost exclusively in males. It is a progressively debilitating disorder; however, the rate of progression varies among affected individuals. At birth, individuals with MPS II do not display any features of the condition. Between ages 2 and 4, they develop full lips, large rounded cheeks, a broad nose, and an enlarged tongue (macroglossia). The vocal cords also enlarge, which results in a deep, hoarse voice. Narrowing of the airway causes frequent upper respiratory infections and short pauses in breathing during sleep (sleep apnea). As the disorder progresses, individuals need medical assistance to keep their airway open. Many other organs and tissues are affected in MPS II. Individuals with this disorder often have a large head (macrocephaly), a buildup of fluid in the brain (hydrocephalus), an enlarged liver and spleen (hepatosplenomegaly), and a soft out-pouching around the belly-button (umbilical hernia) or lower abdomen (inguinal hernia). People with MPS II usually have thick skin that is not very stretchy. Some affected individuals also have distinctive white skin growths that look like pebbles. Most people with this disorder develop hearing loss and have recurrent ear infections. Some individuals with MPS II develop problems with the light-sensitive tissue in the back of the eye (retina) and have reduced vision. Carpal tunnel syndrome commonly occurs in children with this disorder and is characterized by numbness, tingling, and weakness in the hand and fingers. Narrowing of the spinal canal (spinal stenosis) in the neck can compress and damage the spinal cord. The heart is also significantly affected by MPS II, and many individuals develop heart valve problems. Heart valve abnormalities can cause the heart to become enlarged (ventricular hypertrophy) and can eventually lead to heart failure. Children with MPS II grow steadily until about age 5, and then their growth slows and they develop short stature. Individuals with this condition have joint deformities (contractures) that significantly affect mobility. Most people with MPS II also have dysostosis multiplex, which refers to multiple skeletal abnormalities seen on x-ray. Dysostosis multiplex includes a generalized thickening of most long bones, particularly the ribs. There are two types of MPS II, called the severe and mild types. While both types affect many different organs and tissues as described above, people with severe MPS II also experience a decline in intellectual function and a more rapid disease progression. Individuals with the severe form begin to lose basic functional skills (developmentally regress) between the ages of 6 and 8. The life expectancy of these individuals is 10 to 20 years. Individuals with mild MPS II also have a shortened lifespan, but they typically live into adulthood and their intelligence is not affected. Heart disease and airway obstruction are major causes of death in people with both types of MPS II.
mucopolysaccharidosis type II
How many people are affected by mucopolysaccharidosis type II ?
MPS II occurs in approximately 1 in 100,000 to 1 in 170,000 males.
mucopolysaccharidosis type II
What are the genetic changes related to mucopolysaccharidosis type II ?
Mutations in the IDS gene cause MPS II. The IDS gene provides instructions for producing the I2S enzyme, which is involved in the breakdown of large sugar molecules called glycosaminoglycans (GAGs). GAGs were originally called mucopolysaccharides, which is where this condition gets its name. Mutations in the IDS gene reduce or completely eliminate the function of the I2S enzyme. Lack of I2S enzyme activity leads to the accumulation of GAGs within cells, specifically inside the lysosomes. Lysosomes are compartments in the cell that digest and recycle different types of molecules. Conditions that cause molecules to build up inside the lysosomes, including MPS II, are called lysosomal storage disorders. The accumulation of GAGs increases the size of the lysosomes, which is why many tissues and organs are enlarged in this disorder. Researchers believe that the GAGs may also interfere with the functions of other proteins inside the lysosomes and disrupt the movement of molecules inside the cell.
mucopolysaccharidosis type II
Is mucopolysaccharidosis type II inherited ?
This condition is inherited in an X-linked recessive pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation would have to occur in both copies of the gene to cause the disorder. Because it is unlikely that females will have two altered copies of this gene, males are affected by X-linked recessive disorders much more frequently than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.
mucopolysaccharidosis type II
What are the treatments for mucopolysaccharidosis type II ?
These resources address the diagnosis or management of mucopolysaccharidosis type II: - Baby's First Test - Gene Review: Gene Review: Mucopolysaccharidosis Type II - Genetic Testing Registry: Mucopolysaccharidosis, MPS-II - MedlinePlus Encyclopedia: Hunter syndrome - MedlinePlus Encyclopedia: Mucopolysaccharides 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
mucopolysaccharidosis type II
What is (are) celiac disease ?
Celiac disease is a condition in which the immune system is abnormally sensitive to gluten, a protein found in wheat, rye, and barley. Celiac disease is an autoimmune disorder; autoimmune disorders occur when the immune system malfunctions and attacks the body's own tissues and organs. Without a strict, lifelong gluten-free diet, inflammation resulting from immune system overactivity may cause a wide variety of signs and symptoms involving many parts of the body. Celiac disease can develop at any age after an individual starts eating foods containing gluten. The classic symptoms of the condition result from inflammation affecting the gastrointestinal tract. This inflammation damages the villi, which are small, finger-like projections that line the small intestine and provide a greatly increased surface area to absorb nutrients. In celiac disease, the villi become shortened and eventually flatten out. Intestinal damage causes diarrhea and poor absorption of nutrients, which may lead to weight loss. Abdominal pain, swelling (distention), and food intolerances are common in celiac disease. Inflammation associated with celiac disease may lead to an increased risk of developing certain gastrointestinal cancers such as cancers of the small intestine or esophagus. Inflammation and poor nutrient absorption may lead to problems affecting many other organs and systems of the body in affected individuals. These health problems may include iron deficiency that results in a low number of red blood cells (anemia), vitamin deficiencies, low bone mineral density (osteoporosis), itchy skin rashes (dermatitis herpetiformis), defects in the enamel of the teeth, chronic fatigue, joint pain, poor growth, delayed puberty, infertility, or repeated miscarriages. Neurological problems have also been associated with celiac disease; these include migraine headaches, depression, attention deficit hyperactivity disorder (ADHD), and recurrent seizures (epilepsy). Many people with celiac disease have one or more of these varied health problems but do not have gastrointestinal symptoms. This form of the condition is called nonclassic celiac disease. Researchers now believe that nonclassic celiac disease is actually more common than the classic form. Celiac disease often goes undiagnosed because many of its signs and symptoms are nonspecific, which means they may occur in many disorders. Most people who have one or more of these nonspecific health problems do not have celiac disease. On average, a diagnosis of celiac disease is not made until 6 to 10 years after symptoms begin. Some people have silent celiac disease, in which they have no symptoms of the disorder. However, people with silent celiac disease do have immune proteins in their blood (antibodies) that are common in celiac disease. They also have inflammatory damage to their small intestine that can be detected with a biopsy. In a small number of cases, celiac disease does not improve with a gluten-free diet and progresses to a condition called refractory sprue. Refractory sprue is characterized by chronic inflammation of the gastrointestinal tract, poor absorption of nutrients, and an increased risk of developing a type of cancer of the immune cells called T-cell lymphoma.
celiac disease
How many people are affected by celiac disease ?
Celiac disease is a common disorder. Its prevalence has been estimated at about 1 in 100 people worldwide.
celiac disease
What are the genetic changes related to celiac disease ?
The risk of developing celiac disease is increased by certain variants of the HLA-DQA1 and HLA-DQB1 genes. These genes provide instructions for making proteins that play a critical role in the immune system. The HLA-DQA1 and HLA-DQB1 genes belong to a family of genes called the human leukocyte antigen (HLA) complex. The HLA complex helps the immune system distinguish the body's own proteins from proteins made by foreign invaders such as viruses and bacteria. The proteins produced from the HLA-DQA1 and HLA-DQB1 genes attach (bind) to each other to form a functional protein complex called an antigen-binding DQ heterodimer. This complex, which is present on the surface of certain immune system cells, attaches to protein fragments (peptides) outside the cell. If the immune system recognizes the peptides as foreign (such as viral or bacterial peptides), it triggers a response to attack the invading viruses or bacteria. Celiac disease is associated with an inappropriate immune response to a segment of the gluten protein called gliadin. This inappropriate activation of the immune system causes inflammation that damages the body's organs and tissues and leads to the signs and symptoms of celiac disease. Almost all people with celiac disease have specific variants of the HLA-DQA1 and HLA-DQB1 genes, which seem to increase the risk of an inappropriate immune response to gliadin. However, these variants are also found in 30 percent of the general population, and only 3 percent of individuals with the gene variants develop celiac disease. It appears likely that other contributors, such as environmental factors and changes in other genes, also influence the development of this complex disorder.
celiac disease
Is celiac disease inherited ?
Celiac disease tends to cluster in families. Parents, siblings, or children (first-degree relatives) of people with celiac disease have between a 4 and 15 percent chance of developing the disorder. However, the inheritance pattern is unknown.
celiac disease
What are the treatments for celiac disease ?
These resources address the diagnosis or management of celiac disease: - Beth Israel Deaconess: Celiac Center - Columbia University Celiac Disease Center - Gene Review: Gene Review: Celiac Disease - Genetic Testing Registry: Celiac disease - Massachusetts General Hospital Center for Celiac Research and Treatment - MedlinePlus Encyclopedia: Celiac Disease Nutritional Considerations - North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition: Gluten-Free Diet Guide - University of Chicago Celiac Disease Center 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
celiac disease
What is (are) IRAK-4 deficiency ?
IRAK-4 deficiency is an inherited disorder of the immune system (primary immunodeficiency). This immunodeficiency leads to recurrent infections by a subset of bacteria known as pyogenic bacteria but not by other infectious agents. (Infection with pyogenic bacteria causes the production of pus.) The most common infections in IRAK-4 deficiency are caused by the Streptococcus pneumoniae, Staphylococcus aureus, and Pseudomonas aeruginosa bacteria. Most people with this condition have their first bacterial infection before age 2, and the infections can be life-threatening in infancy and childhood. Infections become less frequent with age. Most people with IRAK-4 deficiency have invasive bacterial infections, which can involve the blood (septicemia), the membrane covering the brain and spinal cord (meningitis), or the joints (leading to inflammation and arthritis). Invasive infections can also cause areas of tissue breakdown and pus production (abscesses) on internal organs. In addition, affected individuals can have localized infections of the upper respiratory tract, skin, or eyes. Although fever is a common reaction to bacterial infections, many people with IRAK-4 deficiency do not at first develop a high fever in response to these infections, even if the infection is severe.
IRAK-4 deficiency
How many people are affected by IRAK-4 deficiency ?
IRAK-4 deficiency is a very rare condition, although the exact prevalence is unknown. At least 49 individuals with this condition have been described in the scientific literature.
IRAK-4 deficiency
What are the genetic changes related to IRAK-4 deficiency ?
IRAK-4 deficiency is caused by mutations in the IRAK4 gene, which provides instructions for making a protein that plays an important role in stimulating the immune system to respond to infection. The IRAK-4 protein is part of a signaling pathway that is involved in early recognition of foreign invaders (pathogens) and the initiation of inflammation to fight infection. This signaling pathway is part of the innate immune response, which is the body's early, nonspecific response to pathogens. Mutations in the IRAK4 gene lead to the production of a nonfunctional protein or no protein at all. The loss of functional IRAK-4 protein prevents the immune system from triggering inflammation in response to pathogens that would normally help fight the infections. Because the early immune response is insufficient, bacterial infections occur often and become severe and invasive.
IRAK-4 deficiency
Is IRAK-4 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.
IRAK-4 deficiency
What are the treatments for IRAK-4 deficiency ?
These resources address the diagnosis or management of IRAK-4 deficiency: - Genetic Testing Registry: IRAK4 deficiency 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
IRAK-4 deficiency
What is (are) Weissenbacher-Zweymller syndrome ?
Weissenbacher-Zweymller syndrome is a condition that affects bone growth. It is characterized by skeletal abnormalities, hearing loss, and distinctive facial features. This condition has features that are similar to those of another skeletal disorder, otospondylomegaepiphyseal dysplasia (OSMED). Infants born with Weissenbacher-Zweymller syndrome are smaller than average because the bones in their arms and legs are unusually short. The thigh and upper arm bones are shaped like dumbbells, and the bones of the spine (vertebrae) may also be abnormally shaped. High-tone hearing loss occurs in some cases. Distinctive facial features include wide-set protruding eyes, a small, upturned nose with a flat bridge, and a small lower jaw. Some affected infants are born with an opening in the roof of the mouth (a cleft palate). The skeletal features of Weissenbacher-Zweymller syndrome tend to diminish during childhood. Most adults with this condition are not unusually short, but do still retain the other features of Weissenbacher-Zweymller syndrome.
Weissenbacher-Zweymller syndrome
How many people are affected by Weissenbacher-Zweymller syndrome ?
Weissenbacher-Zweymller syndrome is very rare; only a few families with the disorder have been reported worldwide.
Weissenbacher-Zweymller syndrome
What are the genetic changes related to Weissenbacher-Zweymller syndrome ?
Mutations in the COL11A2 gene cause Weissenbacher-Zweymller syndrome. The COL11A2 gene is one of several genes that provide instructions for the production of type XI collagen. This type of collagen is important for the normal development of bones and other connective tissues that form the body's supportive framework. At least one mutation in the COL11A2 gene is known to cause Weissenbacher-Zweymller syndrome. This mutation disrupts the assembly of type XI collagen molecules, resulting in delayed bone development and the other features of this disorder.
Weissenbacher-Zweymller syndrome
Is Weissenbacher-Zweymller 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.
Weissenbacher-Zweymller syndrome
What are the treatments for Weissenbacher-Zweymller syndrome ?
These resources address the diagnosis or management of Weissenbacher-Zweymller syndrome: - Genetic Testing Registry: Weissenbacher-Zweymuller 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
Weissenbacher-Zweymller syndrome
What is (are) hereditary angioedema ?
Hereditary angioedema is a disorder characterized by recurrent episodes of severe swelling (angioedema). The most common areas of the body to develop swelling are the limbs, face, intestinal tract, and airway. Minor trauma or stress may trigger an attack, but swelling often occurs without a known trigger. Episodes involving the intestinal tract cause severe abdominal pain, nausea, and vomiting. Swelling in the airway can restrict breathing and lead to life-threatening obstruction of the airway. About one-third of people with this condition develop a non-itchy rash called erythema marginatum during an attack. Symptoms of hereditary angioedema typically begin in childhood and worsen during puberty. On average, untreated individuals have an attack every 1 to 2 weeks, and most episodes last for about 3 to 4 days. The frequency and duration of attacks vary greatly among people with hereditary angioedema, even among people in the same family. There are three types of hereditary angioedema, called types I, II, and III, which can be distinguished by their underlying causes and levels of a protein called C1 inhibitor in the blood. The different types have similar signs and symptoms. Type III was originally thought to occur only in women, but families with affected males have been identified.
hereditary angioedema
How many people are affected by hereditary angioedema ?
Hereditary angioedema is estimated to affect 1 in 50,000 people. Type I is the most common, accounting for 85 percent of cases. Type II occurs in 15 percent of cases, and type III is very rare.
hereditary angioedema
What are the genetic changes related to hereditary angioedema ?
Mutations in the SERPING1 gene cause hereditary angioedema type I and type II. The SERPING1 gene provides instructions for making the C1 inhibitor protein, which is important for controlling inflammation. C1 inhibitor blocks the activity of certain proteins that promote inflammation. Mutations that cause hereditary angioedema type I lead to reduced levels of C1 inhibitor in the blood, while mutations that cause type II result in the production of a C1 inhibitor that functions abnormally. Without the proper levels of functional C1 inhibitor, excessive amounts of a protein fragment (peptide) called bradykinin are generated. Bradykinin promotes inflammation by increasing the leakage of fluid through the walls of blood vessels into body tissues. Excessive accumulation of fluids in body tissues causes the episodes of swelling seen in individuals with hereditary angioedema type I and type II. Mutations in the F12 gene are associated with some cases of hereditary angioedema type III. This gene provides instructions for making a protein called coagulation factor XII. In addition to playing a critical role in blood clotting (coagulation), factor XII is also an important stimulator of inflammation and is involved in the production of bradykinin. Certain mutations in the F12 gene result in the production of factor XII with increased activity. As a result, more bradykinin is generated and blood vessel walls become more leaky, which leads to episodes of swelling in people with hereditary angioedema type III. The cause of other cases of hereditary angioedema type III remains unknown. Mutations in one or more as-yet unidentified genes may be responsible for the disorder in these cases.
hereditary angioedema
Is hereditary angioedema 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. In some 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.
hereditary angioedema
What are the treatments for hereditary angioedema ?
These resources address the diagnosis or management of hereditary angioedema: - Genetic Testing Registry: Hereditary C1 esterase inhibitor deficiency - dysfunctional factor - Genetic Testing Registry: Hereditary angioneurotic edema - Genetic Testing Registry: Hereditary angioneurotic edema with normal C1 esterase inhibitor activity - MedlinePlus Encyclopedia: Hereditary angioedema 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
hereditary angioedema
What is (are) spondylothoracic dysostosis ?
Spondylothoracic dysostosis is a condition characterized by the malformation of the bones of the spine and ribs. The bones of the spine (vertebrae) do not develop properly, which causes them to be misshapen and abnormally joined together (fused). The ribs are also fused at the part nearest the spine (posteriorly), which gives the rib cage its characteristic fan-like or "crab" appearance in x-rays. Affected individuals have short, rigid necks and short midsections because of the bone malformations. As a result, people with spondylothoracic dysostosis have short bodies but normal length arms and legs, called short-trunk dwarfism. The spine and rib abnormalities cause other signs and symptoms of spondylothoracic dysostosis. Infants with this condition are born with a small chest that cannot expand adequately, often leading to life-threatening breathing problems. As the lungs expand, the narrow chest forces the muscle that separates the abdomen from the chest cavity (the diaphragm) down and the abdomen is pushed out. The increased pressure in the abdomen can cause a soft out-pouching around the lower abdomen (inguinal hernia) or belly-button (umbilical hernia). Spondylothoracic dysostosis is sometimes called spondylocostal dysostosis, a similar condition with abnormalities of the spine and ribs. The two conditions have been grouped in the past, and both are referred to as Jarcho-Levin syndrome; however, they are now considered distinct conditions.
spondylothoracic dysostosis
How many people are affected by spondylothoracic dysostosis ?
Spondylothoracic dysostosis affects about one in 200,000 people worldwide. However, it is much more common in people of Puerto Rican ancestry, affecting approximately one in 12,000 people.
spondylothoracic dysostosis
What are the genetic changes related to spondylothoracic dysostosis ?
The MESP2 gene provides instructions for a protein that plays a critical role in the development of vertebrae. Specifically, it is involved in separating vertebrae from one another during early development, a process called somite segmentation. Mutations in the MESP2 gene prevent the production of any protein or lead to the production of an abnormally short, nonfunctional protein. When the MESP2 protein is nonfunctional or absent, somite segmentation does not occur properly, which results in the malformation and fusion of the bones of the spine and ribs seen in spondylothoracic dysostosis.
spondylothoracic dysostosis
Is spondylothoracic dysostosis 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.
spondylothoracic dysostosis
What are the treatments for spondylothoracic dysostosis ?
These resources address the diagnosis or management of spondylothoracic dysostosis: - Cleveland Clinic: Spine X-ray - Gene Review: Gene Review: Spondylocostal Dysostosis, Autosomal Recessive 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
spondylothoracic dysostosis
What is (are) juvenile idiopathic arthritis ?
Juvenile idiopathic arthritis refers to a group of conditions involving joint inflammation (arthritis) that first appears before the age of 16. This condition is an autoimmune disorder, which means that the immune system malfunctions and attacks the body's organs and tissues, in this case the joints. Researchers have described seven types of juvenile idiopathic arthritis. The types are distinguished by their signs and symptoms, the number of joints affected, the results of laboratory tests, and the family history. Systemic juvenile idiopathic arthritis causes inflammation in one or more joints. A high daily fever that lasts at least 2 weeks either precedes or accompanies the arthritis. Individuals with systemic arthritis may also have a skin rash or enlargement of the lymph nodes (lymphadenopathy), liver (hepatomegaly), or spleen (splenomegaly). Oligoarticular juvenile idiopathic arthritis (also known as oligoarthritis) has no features other than joint inflammation. Oligoarthritis is marked by the occurrence of arthritis in four or fewer joints in the first 6 months of the disease. It is divided into two subtypes depending on the course of disease. If the arthritis is confined to four or fewer joints after 6 months, then the condition is classified as persistent oligoarthritis. If more than four joints are affected after 6 months, this condition is classified as extended oligoarthritis. Rheumatoid factor positive polyarticular juvenile idiopathic arthritis (also known as polyarthritis, rheumatoid factor positive) causes inflammation in five or more joints within the first 6 months of the disease. Individuals with this condition also have a positive blood test for proteins called rheumatoid factors. This type of arthritis closely resembles rheumatoid arthritis as seen in adults. Rheumatoid factor negative polyarticular juvenile idiopathic arthritis (also known as polyarthritis, rheumatoid factor negative) is also characterized by arthritis in five or more joints within the first 6 months of the disease. Individuals with this type, however, test negative for rheumatoid factor in the blood. Psoriatic juvenile idiopathic arthritis involves arthritis that usually occurs in combination with a skin disorder called psoriasis. Psoriasis is a condition characterized by patches of red, irritated skin that are often covered by flaky white scales. Some affected individuals develop psoriasis before arthritis while others first develop arthritis. Other features of psoriatic arthritis include abnormalities of the fingers and nails or eye problems. Enthesitis-related juvenile idiopathic arthritis is characterized by tenderness where the bone meets a tendon, ligament or other connective tissue. This tenderness, known as enthesitis, accompanies the joint inflammation of arthritis. Enthesitis-related arthritis may also involve inflammation in parts of the body other than the joints. The last type of juvenile idiopathic arthritis is called undifferentiated arthritis. This classification is given to affected individuals who do not fit into any of the above types or who fulfill the criteria for more than one type of juvenile idiopathic arthritis.
juvenile idiopathic arthritis
How many people are affected by juvenile idiopathic arthritis ?
The incidence of juvenile idiopathic arthritis in North America and Europe is estimated to be 4 to 16 in 10,000 children. One in 1,000, or approximately 294,000, children in the United States are affected. The most common type of juvenile idiopathic arthritis in the United States is oligoarticular juvenile idiopathic arthritis, which accounts for about half of all cases. For reasons that are unclear, females seem to be affected with juvenile idiopathic arthritis somewhat more frequently than males. However, in enthesitis-related juvenile idiopathic arthritis males are affected more often than females. The incidence of juvenile idiopathic arthritis varies across different populations and ethnic groups.
juvenile idiopathic arthritis
What are the genetic changes related to juvenile idiopathic arthritis ?
Juvenile idiopathic arthritis is thought to arise from a combination of genetic and environmental factors. The term "idiopathic" indicates that the specific cause of the disorder is unknown. Its signs and symptoms result from excessive inflammation in and around the joints. Inflammation occurs when the immune system sends signaling molecules and white blood cells to a site of injury or disease to fight microbial invaders and facilitate tissue repair. Normally, the body stops the inflammatory response after healing is complete to prevent damage to its own cells and tissues. In people with juvenile idiopathic arthritis, the inflammatory response is prolonged, particularly during movement of the joints. The reasons for this excessive inflammatory response are unclear. Researchers have identified changes in several genes that may influence the risk of developing juvenile idiopathic arthritis. Many of these genes belong to a family of genes that provide instructions for making a group of related proteins called the human leukocyte antigen (HLA) complex. The HLA complex helps the immune system distinguish the body's own proteins from proteins made by foreign invaders (such as viruses and bacteria). Each HLA gene has many different normal variations, allowing each person's immune system to react to a wide range of foreign proteins. Certain normal variations of several HLA genes seem to affect the risk of developing juvenile idiopathic arthritis, and the specific type of the condition that a person may have. Normal variations in several other genes have also been associated with juvenile idiopathic arthritis. Many of these genes are thought to play roles in immune system function. Additional unknown genetic influences and environmental factors, such as infection and other issues that affect immune health, are also likely to influence a person's chances of developing this complex disorder.
juvenile idiopathic arthritis
Is juvenile idiopathic arthritis inherited ?
Most cases of juvenile idiopathic arthritis are sporadic, which means they occur in people with no history of the disorder in their family. A small percentage of cases of juvenile idiopathic arthritis have been reported to run in families, although the inheritance pattern of the condition is unclear. A sibling of a person with juvenile idiopathic arthritis has an estimated risk of developing the condition that is about 12 times that of the general population.
juvenile idiopathic arthritis
What are the treatments for juvenile idiopathic arthritis ?
These resources address the diagnosis or management of juvenile idiopathic arthritis: - American College of Rheumatology: Arthritis in Children - Genetic Testing Registry: Rheumatoid arthritis, systemic juvenile 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
juvenile idiopathic arthritis
What is (are) spina bifida ?
Spina bifida is a condition in which the neural tube, a layer of cells that ultimately develops into the brain and spinal cord, fails to close completely during the first few weeks of embryonic development. As a result, when the spine forms, the bones of the spinal column do not close completely around the developing nerves of the spinal cord. Part of the spinal cord may stick out through an opening in the spine, leading to permanent nerve damage. Because spina bifida is caused by abnormalities of the neural tube, it is classified as a neural tube defect. Children born with spina bifida often have a fluid-filled sac on their back that is covered by skin, called a meningocele. If the sac contains part of the spinal cord and its protective covering, it is known as a myelomeningocele. The signs and symptoms of these abnormalities range from mild to severe, depending on where the opening in the spinal column is located and how much of the spinal cord is affected. Related problems can include a loss of feeling below the level of the opening, weakness or paralysis of the feet or legs, and problems with bladder and bowel control. Some affected individuals have additional complications, including a buildup of excess fluid around the brain (hydrocephalus) and learning problems. With surgery and other forms of treatment, many people with spina bifida live into adulthood. In a milder form of the condition, called spina bifida occulta, the bones of the spinal column are abnormally formed, but the nerves of the spinal cord usually develop normally. Unlike in the more severe form of spina bifida, the nerves do not stick out through an opening in the spine. Spina bifida occulta most often causes no health problems, although rarely it can cause back pain or changes in bladder function.
spina bifida
How many people are affected by spina bifida ?
Spina bifida is one of the most common types of neural tube defect, affecting an estimated 1 in 2,500 newborns worldwide. For unknown reasons, the prevalence of spina bifida varies among different geographic regions and ethnic groups. In the United States, this condition occurs more frequently in Hispanics and non-Hispanic whites than in African Americans.
spina bifida
What are the genetic changes related to spina bifida ?
Spina bifida is a complex condition that is likely caused by the interaction of multiple genetic and environmental factors. Some of these factors have been identified, but many remain unknown. Changes in dozens of genes in individuals with spina bifida and in their mothers may influence the risk of developing this type of neural tube defect. The best-studied of these genes is MTHFR, which provides instructions for making a protein that is involved in processing the vitamin folate (also called vitamin B9). A shortage (deficiency) of this vitamin is an established risk factor for neural tube defects. Changes in other genes related to folate processing and genes involved in the development of the neural tube have also been studied as potential risk factors for spina bifida. However, none of these genes appears to play a major role in causing the condition. Researchers have also examined environmental factors that could contribute to the risk of spina bifida. As mentioned above, folate deficiency appears to play a significant role. Studies have shown that women who take supplements containing folic acid (the synthetic form of folate) before they get pregnant and very early in their pregnancy are significantly less likely to have a baby with spina bifida or a related neural tube defect. Other possible maternal risk factors for spina bifida include diabetes mellitus, obesity, exposure to high heat (such as a fever or use of a hot tub or sauna) in early pregnancy, and the use of certain anti-seizure medications during pregnancy. However, it is unclear how these factors may influence the risk of spina bifida.
spina bifida
Is spina bifida inherited ?
Most cases of spina bifida are sporadic, which means they occur in people with no history of the disorder in their family. A small percentage of cases have been reported to run in families; however, the condition does not have a clear pattern of inheritance. First-degree relatives (such as siblings and children) of people with spina bifida have an increased risk of the condition compared with people in the general population.
spina bifida
What are the treatments for spina bifida ?
These resources address the diagnosis or management of spina bifida: - Benioff Children's Hospital, University of California, San Francisco: Treatment of Spina Bifida - Centers for Disease Control and Prevention: Living with Spina Bifida - GeneFacts: Spina Bifida: Diagnosis - GeneFacts: Spina Bifida: Management - Genetic Testing Registry: Neural tube defect - Genetic Testing Registry: Neural tube defects, folate-sensitive - Spina Bifida Association: Urologic Care and Management - University of California, San Francisco Fetal Treatment Center 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
spina bifida
What is (are) Jervell and Lange-Nielsen syndrome ?
Jervell and Lange-Nielsen syndrome is a condition that causes profound hearing loss from birth and a disruption of the heart's normal rhythm (arrhythmia). This disorder is a form of long QT syndrome, which is a heart condition that causes the heart (cardiac) muscle to take longer than usual to recharge between beats. Beginning in early childhood, the irregular heartbeats increase the risk of fainting (syncope) and sudden death.
Jervell and Lange-Nielsen syndrome
How many people are affected by Jervell and Lange-Nielsen syndrome ?
Jervell and Lange-Nielsen syndrome is uncommon; it affects an estimated 1.6 to 6 per 1 million people worldwide. This condition has a higher prevalence in Denmark, where it affects at least 1 in 200,000 people.
Jervell and Lange-Nielsen syndrome
What are the genetic changes related to Jervell and Lange-Nielsen syndrome ?
Mutations in the KCNE1 and KCNQ1 genes cause Jervell and Lange-Nielsen syndrome. The KCNE1 and KCNQ1 genes provide instructions for making proteins that work together to form a channel across cell membranes. These channels transport positively charged potassium atoms (ions) out of cells. The movement of potassium ions through these channels is critical for maintaining the normal functions of inner ear structures and cardiac muscle. About 90 percent of cases of Jervell and Lange-Nielsen syndrome are caused by mutations in the KCNQ1 gene; KCNE1 mutations are responsible for the remaining cases. Mutations in these genes alter the usual structure and function of potassium channels or prevent the assembly of normal channels. These changes disrupt the flow of potassium ions in the inner ear and in cardiac muscle, leading to hearing loss and an irregular heart rhythm characteristic of Jervell and Lange-Nielsen syndrome.
Jervell and Lange-Nielsen syndrome
Is Jervell and Lange-Nielsen syndrome 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 a child with an autosomal recessive disorder are not affected, but are carriers of one copy of the mutated gene. Some carriers of a KCNQ1 or KCNE1 mutation have signs and symptoms affecting the heart, but their hearing is usually normal.
Jervell and Lange-Nielsen syndrome
What are the treatments for Jervell and Lange-Nielsen syndrome ?
These resources address the diagnosis or management of Jervell and Lange-Nielsen syndrome: - Gene Review: Gene Review: Jervell and Lange-Nielsen Syndrome - Genetic Testing Registry: Jervell and Lange-Nielsen syndrome - 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
Jervell and Lange-Nielsen syndrome
What is (are) phosphoribosylpyrophosphate synthetase superactivity ?
Phosphoribosylpyrophosphate synthetase superactivity (PRS superactivity) is characterized by the overproduction and accumulation of uric acid (a waste product of normal chemical processes) in the blood and urine. The overproduction of uric acid can lead to gout, which is arthritis caused by an accumulation of uric acid crystals in the joints. Individuals with PRS superactivity also develop kidney or bladder stones that may result in episodes of acute kidney failure. There are two forms of PRS superactivity, a severe form that begins in infancy or early childhood, and a milder form that typically appears in late adolescence or early adulthood. In both forms, a kidney or bladder stone is often the first symptom. Gout and impairment of kidney function may develop if the condition is not adequately controlled with medication and dietary restrictions. People with the severe form may also have neurological problems, including hearing loss caused by changes in the inner ear (sensorineural hearing loss), weak muscle tone (hypotonia), impaired muscle coordination (ataxia), and developmental delay.
phosphoribosylpyrophosphate synthetase superactivity
How many people are affected by phosphoribosylpyrophosphate synthetase superactivity ?
PRS superactivity is believed to be a rare disorder. Approximately 30 families with the condition have been reported. More than two thirds of these families are affected by the milder form of the disease.
phosphoribosylpyrophosphate synthetase superactivity
What are the genetic changes related to phosphoribosylpyrophosphate synthetase superactivity ?
Certain mutations in the PRPS1 gene cause PRS superactivity. The PRPS1 gene provides instructions for making an enzyme called phosphoribosyl pyrophosphate synthetase 1, or PRPP synthetase 1. This enzyme helps produce a molecule called phosphoribosyl pyrophosphate (PRPP). PRPP is involved in producing purine and pyrimidine nucleotides. These nucleotides are building blocks of DNA, its chemical cousin RNA, and molecules such as ATP and GTP that serve as energy sources in the cell. PRPP synthetase 1 and PRPP also play a key role in recycling purines from the breakdown of DNA and RNA, a faster and more efficient way of making purines available. In people with the more severe form of PRS superactivity, PRPS1 gene mutations change single protein building blocks (amino acids) in the PRPP synthetase 1 enzyme, resulting in a poorly regulated, overactive enzyme. In the milder form of PRS superactivity, the PRPS1 gene is overactive for reasons that are not well understood. PRPS1 gene overactivity increases the production of normal PRPP synthetase 1 enzyme, which increases the availability of PRPP. In both forms of the disorder, excessive amounts of purines are generated. Under these conditions, uric acid, a waste product of purine breakdown, accumulates in the body. A buildup of uric acid crystals can cause gout, kidney stones, and bladder stones. It is unclear how PRPS1 gene mutations are related to the neurological problems associated with the severe form of PRS superactivity.
phosphoribosylpyrophosphate synthetase superactivity
Is phosphoribosylpyrophosphate synthetase superactivity inherited ?
This condition is inherited in an X-linked pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), a mutation in the only copy of the gene in each cell causes the disorder. In females (who have two X chromosomes), a mutation in one of the two copies of the gene in each cell sometimes causes the disorder. In most reported cases, affected individuals have inherited the mutation from a parent who carries an altered copy of the PRPS1 gene. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. PRS superactivity may also result from new mutations in the PRPS1 gene and can occur in people with no history of the disorder in their family.
phosphoribosylpyrophosphate synthetase superactivity
What are the treatments for phosphoribosylpyrophosphate synthetase superactivity ?
These resources address the diagnosis or management of PRS superactivity: - Gene Review: Gene Review: Phosphoribosylpyrophosphate Synthetase Superactivity - Genetic Testing Registry: Phosphoribosylpyrophosphate synthetase superactivity - MedlinePlus Encyclopedia: Hearing Loss - MedlinePlus Encyclopedia: Movement, Uncoordinated 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
phosphoribosylpyrophosphate synthetase superactivity
What is (are) short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay ?
Short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay, commonly known by the acronym SHORT syndrome, is a rare disorder that affects many parts of the body. Most people with SHORT syndrome are small at birth and gain weight slowly in childhood. Affected adults tend to have short stature compared with others in their family. Many have a lack of fatty tissue under the skin (lipoatrophy), primarily in the face, arms, and chest. This lack of fat, together with thin, wrinkled skin and veins visible beneath the skin, makes affected individuals look older than their biological age. This appearance of premature aging is sometimes described as progeroid. Most people with SHORT syndrome have distinctive facial features. These include a triangular face shape with a prominent forehead and deep-set eyes (ocular depression), thin nostrils, a downturned mouth, and a small chin. Eye abnormalities are common in affected individuals, particularly Rieger anomaly, which affects structures at the front of the eye. Rieger anomaly can be associated with increased pressure in the eye (glaucoma) and vision loss. Some people with SHORT syndrome also have dental abnormalities such as delayed appearance (eruption) of teeth in early childhood, small teeth, fewer teeth than normal (hypodontia), and a lack of protective covering (enamel) on the surface of the teeth. Other signs and symptoms that have been reported in people with SHORT syndrome include immune system abnormalities, a kidney disorder known as nephrocalcinosis, hearing loss, loose (hyperextensible) joints, and a soft out-pouching in the lower abdomen called an inguinal hernia. A few affected individuals have developed problems with blood sugar regulation including insulin resistance and diabetes. Most people with SHORT syndrome have normal intelligence, although a few have been reported with mild cognitive impairment or delayed development of speech in childhood.
short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay
How many people are affected by short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay ?
SHORT syndrome is a rare condition; its prevalence is unknown. Only a few affected individuals and families have been reported worldwide.
short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay
What are the genetic changes related to short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay ?
SHORT syndrome results from mutations in the PIK3R1 gene. This gene provides instructions for making one part (subunit) of an enzyme called PI3K, which plays a role in chemical signaling within cells. PI3K signaling is important for many cell activities, including cell growth and division, movement (migration) of cells, production of new proteins, transport of materials within cells, and cell survival. Studies suggest that PI3K signaling may be involved in the regulation of several hormones, including insulin, which helps control blood sugar levels. PI3K signaling may also play a role in the maturation of fat cells (adipocytes). Mutations in the PIK3R1 gene alter the structure of the subunit, which reduces the ability of PI3K to participate in cell signaling. Researchers are working to determine how these changes lead to the specific features of SHORT syndrome. PI3K's role in insulin activity may be related to the development of insulin resistance and diabetes, and problems with adipocyte maturation might contribute to lipoatrophy in affected individuals. It is unclear how reduced PI3K signaling is associated with the other features of the condition.
short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay
Is short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay inherited ?
SHORT syndrome has an autosomal dominant pattern of inheritance, which means one copy of the altered PIK3R1 gene in each cell is sufficient to cause the disorder. In most cases, the condition results from a new mutation in the gene and occurs in people with no history of the disorder in their family. In other cases, an affected person inherits the mutation from one affected parent.
short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay
What are the treatments for short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay ?
These resources address the diagnosis or management of SHORT syndrome: - Gene Review: Gene Review: SHORT Syndrome - Genetic Testing Registry: SHORT 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
short stature, hyperextensibility, hernia, ocular depression, Rieger anomaly, and teething delay
What is (are) Ochoa syndrome ?
Ochoa syndrome is a disorder characterized by urinary problems and unusual facial expressions. The urinary problems associated with Ochoa syndrome typically become apparent in early childhood or adolescence. People with this disorder may have difficulty controlling the flow of urine (incontinence), which can lead to bedwetting. Individuals with Ochoa syndrome may be unable to completely empty the bladder, often resulting in vesicoureteral reflux, a condition in which urine backs up into the ducts that normally carry it from each kidney to the bladder (the ureters). Urine may also accumulate in the kidneys (hydronephrosis). Vesicoureteral reflux and hydronephrosis can lead to frequent infections of the urinary tract and kidney inflammation (pyelonephritis), causing damage that may eventually result in kidney failure. Individuals with Ochoa syndrome also exhibit a characteristic frown-like facial grimace when they try to smile or laugh, often described as inversion of facial expression. While this feature may appear earlier than the urinary tract symptoms, perhaps as early as an infant begins to smile, it is often not brought to medical attention. Approximately two-thirds of individuals with Ochoa syndrome also experience problems with bowel function, such as constipation, loss of bowel control, or muscle spasms of the anus.
Ochoa syndrome
How many people are affected by Ochoa syndrome ?
Ochoa syndrome is a rare disorder. About 150 cases have been reported in the medical literature.
Ochoa syndrome
What are the genetic changes related to Ochoa syndrome ?
Ochoa syndrome can be caused by mutations in the HPSE2 gene. This gene provides instructions for making a protein called heparanase 2. The function of this protein is not well understood. Mutations in the HPSE2 gene that cause Ochoa syndrome result in changes in the heparanase 2 protein that likely prevent it from functioning. The connection between HPSE2 gene mutations and the features of Ochoa syndrome are unclear. Because the areas of the brain that control facial expression and urination are in close proximity, some researchers have suggested that the genetic changes may lead to an abnormality in this brain region that may account for the symptoms of Ochoa syndrome. Other researchers believe that a defective heparanase 2 protein may lead to problems with the development of the urinary tract or with muscle function in the face and bladder. Some people with Ochoa syndrome do not have mutations in the HPSE2 gene. In these individuals, the cause of the disorder is unknown.
Ochoa syndrome
Is Ochoa 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.
Ochoa syndrome
What are the treatments for Ochoa syndrome ?
These resources address the diagnosis or management of Ochoa syndrome: - Gene Review: Gene Review: Urofacial Syndrome - Genetic Testing Registry: Ochoa syndrome - National Institute of Diabetes and Digestive and Kidney Diseases: Urodynamic Testing - Scripps Health: Self-Catheterization -- Female - Scripps Health: Self-Catheterization -- Male 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
Ochoa syndrome
What is (are) Rubinstein-Taybi syndrome ?
Rubinstein-Taybi syndrome is a condition characterized by short stature, moderate to severe intellectual disability, distinctive facial features, and broad thumbs and first toes. Additional features of the disorder can include eye abnormalities, heart and kidney defects, dental problems, and obesity. These signs and symptoms vary among affected individuals. People with this condition have an increased risk of developing noncancerous and cancerous tumors, including certain kinds of brain tumors. Cancer of blood-forming tissue (leukemia) also occurs more frequently in people with Rubinstein-Taybi syndrome. Rarely, Rubinstein-Taybi syndrome can involve serious complications such as a failure to gain weight and grow at the expected rate (failure to thrive) and life-threatening infections. Infants born with this severe form of the disorder usually survive only into early childhood.
Rubinstein-Taybi syndrome
How many people are affected by Rubinstein-Taybi syndrome ?
This condition is uncommon; it occurs in an estimated 1 in 100,000 to 125,000 newborns.
Rubinstein-Taybi syndrome
What are the genetic changes related to Rubinstein-Taybi syndrome ?
Mutations in the CREBBP gene are responsible for some cases of Rubinstein-Taybi syndrome. The CREBBP gene provides instructions for making a protein that helps control the activity of many other genes. This protein, called CREB binding protein, plays an important role in regulating cell growth and division and is essential for normal fetal development. If one copy of the CREBBP gene is deleted or mutated, cells make only half of the normal amount of CREB binding protein. Although a reduction in the amount of this protein disrupts normal development before and after birth, researchers have not determined how it leads to the specific signs and symptoms of Rubinstein-Taybi syndrome. Mutations in the EP300 gene cause a small percentage of cases of Rubinstein-Taybi syndrome. Like the CREBBP gene, this gene provides instructions for making a protein that helps control the activity of other genes. It also appears to be important for development before and after birth. EP300 mutations inactivate one copy of the gene in each cell, which interferes with normal development and causes the typical features of Rubinstein-Taybi syndrome. The signs and symptoms of this disorder in people with EP300 mutations are similar to those with mutations in the CREBBP gene; however, studies suggest that EP300 mutations may be associated with milder skeletal changes in the hands and feet. Some cases of severe Rubinstein-Taybi syndrome have resulted from a deletion of genetic material from the short (p) arm of chromosome 16. Several genes, including the CREBBP gene, are missing as a result of this deletion. Researchers believe that the loss of multiple genes in this region probably accounts for the serious complications associated with severe Rubinstein-Taybi syndrome. About half of people with Rubinstein-Taybi syndrome do not have an identified mutation in the CREBBP or EP300 gene or a deletion in chromosome 16. The cause of the condition is unknown in these cases. Researchers predict that mutations in other genes are also responsible for the disorder.
Rubinstein-Taybi syndrome
Is Rubinstein-Taybi syndrome inherited ?
This condition is considered 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. Most cases result from new mutations in the gene and occur in people with no history of the disorder in their family.
Rubinstein-Taybi syndrome
What are the treatments for Rubinstein-Taybi syndrome ?
These resources address the diagnosis or management of Rubinstein-Taybi syndrome: - Gene Review: Gene Review: Rubinstein-Taybi Syndrome - Genetic Testing Registry: Rubinstein-Taybi syndrome - MedlinePlus Encyclopedia: Rubinstein-Taybi 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
Rubinstein-Taybi syndrome
What is (are) blepharophimosis, ptosis, and epicanthus inversus syndrome ?
Blepharophimosis, ptosis, and epicanthus inversus syndrome (BPES) is a condition that mainly affects development of the eyelids. People with this condition have a narrowing of the eye opening (blepharophimosis), droopy eyelids (ptosis), and an upward fold of the skin of the lower eyelid near the inner corner of the eye (epicanthus inversus). In addition, there is an increased distance between the inner corners of the eyes (telecanthus). Because of these eyelid abnormalities, the eyelids cannot open fully, and vision may be limited. Other structures in the eyes and face may be mildly affected by BPES. Affected individuals are at an increased risk of developing vision problems such as nearsightedness (myopia) or farsightedness (hyperopia) beginning in childhood. They may also have eyes that do not point in the same direction (strabismus) or "lazy eye" (amblyopia) affecting one or both eyes. People with BPES may also have distinctive facial features including a broad nasal bridge, low-set ears, or a shortened distance between the nose and upper lip (a short philtrum). There are two types of BPES, which are distinguished by their signs and symptoms. Both types I and II include the eyelid malformations and other facial features. Type I is also associated with an early loss of ovarian function (primary ovarian insufficiency) in women, which causes their menstrual periods to become less frequent and eventually stop before age 40. Primary ovarian insufficiency can lead to difficulty conceiving a child (subfertility) or a complete inability to conceive (infertility).
blepharophimosis, ptosis, and epicanthus inversus syndrome
How many people are affected by blepharophimosis, ptosis, and epicanthus inversus syndrome ?
The prevalence of BPES is unknown.
blepharophimosis, ptosis, and epicanthus inversus syndrome
What are the genetic changes related to blepharophimosis, ptosis, and epicanthus inversus syndrome ?
Mutations in the FOXL2 gene cause BPES types I and II. The FOXL2 gene provides instructions for making a protein that is active in the eyelids and ovaries. The FOXL2 protein is likely involved in the development of muscles in the eyelids. Before birth and in adulthood, the protein regulates the growth and development of certain ovarian cells and the breakdown of specific molecules. It is difficult to predict the type of BPES that will result from the many FOXL2 gene mutations. However, mutations that result in a partial loss of FOXL2 protein function generally cause BPES type II. These mutations probably impair regulation of normal development of muscles in the eyelids, resulting in malformed eyelids that cannot open fully. Mutations that lead to a complete loss of FOXL2 protein function often cause BPES type I. These mutations impair the regulation of eyelid development as well as various activities in the ovaries, resulting in eyelid malformation and abnormally accelerated maturation of certain ovarian cells and the premature death of egg cells.
blepharophimosis, ptosis, and epicanthus inversus syndrome
Is blepharophimosis, ptosis, and epicanthus inversus syndrome inherited ?
This condition is typically inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In some 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.
blepharophimosis, ptosis, and epicanthus inversus syndrome
What are the treatments for blepharophimosis, ptosis, and epicanthus inversus syndrome ?
These resources address the diagnosis or management of BPES: - Gene Review: Gene Review: Blepharophimosis, Ptosis, and Epicanthus Inversus - Genetic Testing Registry: Blepharophimosis, ptosis, and epicanthus inversus - MedlinePlus Encyclopedia: Ptosis 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
blepharophimosis, ptosis, and epicanthus inversus syndrome
What is (are) isolated Duane retraction syndrome ?
Isolated Duane retraction syndrome is a disorder of eye movement. This condition prevents outward movement of the eye (toward the ear), and in some cases may also limit inward eye movement (toward the nose). As the eye moves inward, the eyelids partially close and the eyeball pulls back (retracts) into its socket. Most commonly, only one eye is affected. About 10 percent of people with isolated Duane retraction syndrome develop amblyopia ("lazy eye"), a condition that causes vision loss in the affected eye. About 70 percent of all cases of Duane retraction syndrome are isolated, which means they occur without other signs and symptoms. Duane retraction syndrome can also occur as part of syndromes that affect other areas of the body. For example, Duane-radial ray syndrome is characterized by this eye disorder in conjunction with abnormalities of bones in the arms and hands. Researchers have identified three forms of isolated Duane retraction syndrome, designated types I, II, and III. The types vary in which eye movements are most severely restricted (inward, outward, or both). All three types are characterized by retraction of the eyeball as the eye moves inward.
isolated Duane retraction syndrome
How many people are affected by isolated Duane retraction syndrome ?
Isolated Duane retraction syndrome affects an estimated 1 in 1,000 people worldwide. This condition accounts for 1 percent to 5 percent of all cases of abnormal eye alignment (strabismus). For unknown reasons, isolated Duane syndrome affects females more often than males.
isolated Duane retraction syndrome
What are the genetic changes related to isolated Duane retraction syndrome ?
In most people with isolated Duane retraction syndrome, the cause of the condition is unknown. However, researchers have identified mutations in one gene, CHN1, that cause the disorder in a small number of families. The CHN1 gene provides instructions for making a protein that is involved in the early development of the nervous system. Specifically, the protein appears to be critical for the formation of nerves that control several of the muscles surrounding the eyes (extraocular muscles). Mutations in the CHN1 gene disrupt the normal development of these nerves and the extraocular muscles needed for side-to-side eye movement. Abnormal function of these muscles leads to restricted eye movement and related problems with vision.
isolated Duane retraction syndrome
Is isolated Duane retraction syndrome inherited ?
Isolated Duane retraction syndrome usually occurs in people with no history of the disorder in their family. These cases are described as simplex, and their genetic cause is unknown. Less commonly, isolated Duane retraction syndrome can run in families. Familial cases most often have an autosomal dominant pattern of inheritance, which means one copy of the altered gene in each cell is sufficient to cause the disorder. When isolated Duane retraction syndrome is caused by CHN1 mutations, it has an autosomal dominant inheritance pattern. In a few families with isolated Duane retraction syndrome, the pattern of affected family members suggests autosomal recessive inheritance. In these families, one or more children are affected, although the parents typically have no signs or symptoms of the condition. The parents of children with an autosomal recessive condition are called carriers, which means they carry one mutated copy of a gene in each cell. In affected children, both copies of the gene in each cell are mutated. However, researchers have not discovered the gene or genes responsible for autosomal recessive isolated Duane retraction syndrome.
isolated Duane retraction syndrome
What are the treatments for isolated Duane retraction syndrome ?
These resources address the diagnosis or management of isolated Duane retraction syndrome: - Gene Review: Gene Review: Duane Syndrome - Genetic Testing Registry: Duane's syndrome - MedlinePlus Encyclopedia: Extraocular Muscle Function Testing 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
isolated Duane retraction syndrome
What is (are) autosomal recessive hypotrichosis ?
Autosomal recessive hypotrichosis is a condition that affects hair growth. People with this condition have sparse hair (hypotrichosis) on the scalp beginning in infancy. This hair is usually coarse, dry, and tightly curled (often described as woolly hair). Scalp hair may also be lighter in color than expected and is fragile and easily broken. Affected individuals often cannot grow hair longer than a few inches. The eyebrows, eyelashes, and other body hair may be sparse as well. Over time, the hair problems can remain stable or progress to complete scalp hair loss (alopecia) and a decrease in body hair. Rarely, people with autosomal recessive hypotrichosis have skin problems affecting areas with sparse hair, such as redness (erythema), itchiness (pruritus), or missing patches of skin (erosions) on the scalp. In areas of poor hair growth, they may also develop bumps called hyperkeratotic follicular papules that develop around hair follicles, which are specialized structures in the skin where hair growth occurs.
autosomal recessive hypotrichosis
How many people are affected by autosomal recessive hypotrichosis ?
The worldwide prevalence of autosomal recessive hypotrichosis is unknown. In Japan, the condition is estimated to affect 1 in 10,000 individuals.
autosomal recessive hypotrichosis
What are the genetic changes related to autosomal recessive hypotrichosis ?
Autosomal recessive hypotrichosis can be caused by mutations in the LIPH, LPAR6, or DSG4 gene. These genes provide instructions for making proteins that are involved in the growth and division (proliferation) and maturation (differentiation) of cells within hair follicles. These cell processes are important for the normal development of hair follicles and for hair growth; as the cells in the hair follicle divide, the hair strand (shaft) is pushed upward and extends beyond the skin, causing the hair to grow. The proteins produced from the LIPH, LPAR6, and DSG4 genes are also found in the outermost layer of skin (the epidermis) and glands in the skin that produce a substance that protects the skin and hair (sebaceous glands). Mutations in the LIPH, LPAR6, or DSG4 gene result in the production of abnormal proteins that cannot aid in the development of hair follicles. As a result, hair follicles are structurally abnormal and often underdeveloped. Irregular hair follicles alter the structure and growth of hair shafts, leading to woolly, fragile hair that is easily broken. A lack of these proteins in the epidermis likely contributes to the skin problems sometimes seen in affected individuals. In some areas of the body, other proteins can compensate for the function of the missing protein, so not all areas with hair are affected and not all individuals have skin problems.
autosomal recessive hypotrichosis
Is autosomal recessive hypotrichosis 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.
autosomal recessive hypotrichosis
What are the treatments for autosomal recessive hypotrichosis ?
These resources address the diagnosis or management of autosomal recessive hypotrichosis: - American Academy of Dermatology: Hair Loss: Tips for Managing - Genetic Testing Registry: Hypotrichosis 8 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
autosomal recessive hypotrichosis
What is (are) multiple lentigines syndrome ?
Multiple lentigines syndrome (formerly called LEOPARD syndrome) is a condition that affects many areas of the body. The characteristic features associated with the condition include brown skin spots called lentigines that are similar to freckles, abnormalities in the electrical signals that control the heartbeat, widely spaced eyes (ocular hypertelorism), a narrowing of the artery from the heart to the lungs (pulmonary stenosis), abnormalities of the genitalia, short stature, and hearing loss. These features vary, however, even among affected individuals in the same family. Not all individuals affected with multiple lentigines syndrome have all the characteristic features of this condition. The lentigines seen in multiple lentigines syndrome typically first appear in mid-childhood, mostly on the face, neck, and upper body. Affected individuals may have thousands of brown skin spots by the time they reach puberty. Unlike freckles, the appearance of lentigines has nothing to do with sun exposure. In addition to lentigines, people with this condition may have lighter brown skin spots called caf-au-lait spots. Caf-au-lait spots tend to develop before the lentigines, appearing within the first year of life in most affected people. Abnormal electrical signaling in the heart can be a sign of other heart problems. Of the people with multiple lentigines syndrome who have heart problems, about 80 percent have hypertrophic cardiomyopathy, which is a thickening of the heart muscle that forces the heart to work harder to pump blood. The hypertrophic cardiomyopathy in affected individuals most often affects the lower left chamber of the heart (the left ventricle). Up to 20 percent of people with multiple lentigines syndrome who have heart problems have pulmonary stenosis. People with multiple lentigines syndrome can have a distinctive facial appearance. In addition to ocular hypertelorism, affected individuals may have droopy eyelids (ptosis), thick lips, and low-set ears. Abnormalities of the genitalia occur most often in males with multiple lentigines syndrome. The most common abnormality in affected males is undescended testes (cryptorchidism). Other males may have a urethra that opens on the underside of the penis (hypospadias). Males with multiple lentigines syndrome may have a reduced ability to have biological children (decreased fertility). Females with multiple lentigines syndrome may have poorly developed ovaries and delayed puberty. At birth, people with multiple lentigines syndrome are typically of normal weight and height, but in some, growth slows over time. This slow growth results in short stature in 50 to 75 percent of people with multiple lentigines syndrome. Approximately 20 percent of individuals with multiple lentigines syndrome develop hearing loss. This hearing loss is caused by abnormalities in the inner ear (sensorineural deafness) and can be present from birth or develop later in life. Other signs and symptoms of multiple lentigines syndrome include learning disorders, mild developmental delay, a sunken or protruding chest, and extra folds of skin on the back of the neck. Many of the signs and symptoms of multiple lentigines syndrome also occur in a similar disorder called Noonan syndrome. It can be difficult to tell the two disorders apart in early childhood. However, the features of the two disorders differ later in life.
multiple lentigines syndrome
How many people are affected by multiple lentigines syndrome ?
Multiple lentigines syndrome is thought to be a rare condition; approximately 200 cases have been reported worldwide.
multiple lentigines syndrome
What are the genetic changes related to multiple lentigines syndrome ?
Mutations in the PTPN11, RAF1, or BRAF genes cause multiple lentigines syndrome. Approximately 90 percent of individuals with multiple lentigines syndrome have mutations in the PTPN11 gene. RAF1 and BRAF gene mutations are responsible for a total of about 10 percent of cases. A small proportion of people with multiple lentigines syndrome do not have an identified mutation in any of these three genes. In these individuals, the cause of the condition is unknown. The PTPN11, RAF1, and BRAF genes all provide instructions for making proteins that are involved in important signaling pathways needed for the proper formation of several types of tissue during development. These proteins also play roles in the regulation of cell division, cell movement (migration), and cell differentiation (the process by which cells mature to carry out specific functions). Mutations in the PTPN11, RAF1, or BRAF genes lead to the production of a protein that functions abnormally. This abnormal functioning impairs the protein's ability to respond to cell signals. A disruption in the regulation of systems that control cell growth and division leads to the characteristic features of multiple lentigines syndrome.
multiple lentigines syndrome
Is multiple lentigines 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.
multiple lentigines syndrome
What are the treatments for multiple lentigines syndrome ?
These resources address the diagnosis or management of multiple lentigines syndrome: - Cincinnati Children's Hospital: Cardiomyopathies - Gene Review: Gene Review: Noonan Syndrome with Multiple Lentigines - Genetic Testing Registry: LEOPARD syndrome 1 - Genetic Testing Registry: LEOPARD syndrome 2 - Genetic Testing Registry: LEOPARD syndrome 3 - Genetic Testing Registry: Noonan syndrome with multiple lentigines - MedlinePlus Encyclopedia: Hypertrophic Cardiomyopathy 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
multiple lentigines syndrome