Input: What are the genetic changes related to progressive external ophthalmoplegia ?

Output: Progressive external ophthalmoplegia is a condition caused by defects in mitochondria, which are structures within cells that use oxygen to convert the energy from food into a form cells can use. This process is called oxidative phosphorylation. Although most DNA is packaged in chromosomes within the nucleus (nuclear DNA), mitochondria also have a small amount of their own DNA, called mitochondrial DNA or mtDNA.  Progressive external ophthalmoplegia can result from mutations in several different genes. In some cases, mutations in the MT-TL1 gene, which is located in mtDNA, cause progressive external ophthalmoplegia. In other cases, mutations in nuclear DNA are responsible for the condition, particularly mutations in the POLG, SLC25A4, and C10orf2 genes. These genes are critical for mtDNA maintenance. Although the mechanism is unclear, mutations in any of these three genes lead to large deletions of mtDNA, ranging from 2,000 to 10,000 DNA building blocks (nucleotides).  Researchers have not determined how deletions of mtDNA lead to the specific signs and symptoms of progressive external ophthalmoplegia, although the features of the condition are probably related to impaired oxidative phosphorylation. It has been suggested that eye muscles are commonly affected by mitochondrial defects because they are especially dependent on oxidative phosphorylation for energy. </s>


Input: Is progressive external ophthalmoplegia inherited ?

Output: Progressive external ophthalmoplegia can have different inheritance patterns depending on the gene involved.  When this condition is caused by mutations in the MT-TL1 gene, it is inherited in a mitochondrial pattern, which is also known as maternal inheritance. This pattern of inheritance applies to genes contained in mtDNA. Because egg cells, but not sperm cells, contribute mitochondria to the developing embryo, children can only inherit disorders resulting from mtDNA mutations from their mother. These disorders can appear in every generation of a family and can affect both males and females, but fathers do not pass traits associated with changes in mtDNA to their children.  When the nuclear genes POLG, SLC25A4, or C10orf2 are involved, progressive external ophthalmoplegia is usually inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder.  Certain mutations in the POLG gene can also cause a form of the condition that 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.  Some mutations in the POLG gene that cause progressive external ophthalmoplegia occur during a person's lifetime and are not inherited. These genetic changes are called somatic mutations. </s>


Input: What are the treatments for progressive external ophthalmoplegia ?

Output: These resources address the diagnosis or management of progressive external ophthalmoplegia:  - Gene Review: Gene Review: Mitochondrial DNA Deletion Syndromes  - Gene Review: Gene Review: POLG-Related Disorders  - Genetic Testing Registry: Autosomal dominant progressive external ophthalmoplegia with mitochondrial DNA deletions 1  - Genetic Testing Registry: Autosomal dominant progressive external ophthalmoplegia with mitochondrial DNA deletions 2  - Genetic Testing Registry: Autosomal dominant progressive external ophthalmoplegia with mitochondrial DNA deletions 3  - Genetic Testing Registry: Progressive external ophthalmoplegia  - United Mitochondrial Disease Foundation: Diagnosis of Mitochondrial Disease   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 </s>


Input: What is (are) alveolar capillary dysplasia with misalignment of pulmonary veins ?

Output: Alveolar capillary dysplasia with misalignment of pulmonary veins (ACD/MPV) is a disorder affecting the development of the lungs and their blood vessels. The disorder affects the millions of small air sacs (alveoli) in the lungs and the tiny blood vessels (capillaries) in the alveoli. It is through these alveolar capillaries that inhaled oxygen enters the bloodstream for distribution throughout the body and carbon dioxide leaves the bloodstream to be exhaled.  In ACD/MPV, the alveolar capillaries fail to develop normally. The number of capillaries is drastically reduced, and existing capillaries are improperly positioned within the walls of the alveoli. These abnormalities in capillary number and location impede the exchange of oxygen and carbon dioxide.  Other abnormalities of the blood vessels in the lungs also occur in ACD/MPV. The veins that carry blood from the lungs into the heart (pulmonary veins) are improperly positioned and may be abnormally bundled together with arteries that carry blood from the heart to the lungs (pulmonary arteries). The muscle tissue in the walls of the pulmonary arteries may be overgrown, resulting in thicker artery walls and a narrower channel. These changes restrict normal blood flow, which causes high blood pressure in the pulmonary arteries (pulmonary hypertension) and requires the heart to pump harder.  Most infants with ACD/MPV are born with additional abnormalities. These may include abnormal twisting (malrotation) of the large intestine or other malformations of the gastrointestinal tract. Cardiovascular and genitourinary abnormalities are also common in affected individuals.  Infants with ACD/MPV typically develop respiratory distress within a few minutes to a few hours after birth. They experience shortness of breath and cyanosis, which is a bluish appearance of the skin, mucous membranes, or the area underneath the fingernails caused by a lack of oxygen in the blood. Without lung transplantation, infants with ACD/MPV have not been known to survive past one year of age, and most affected infants live only a few weeks. </s>


Input: How many people are affected by alveolar capillary dysplasia with misalignment of pulmonary veins ?

Output: ACD/MPV is a rare disorder; its incidence is unknown. Approximately 200 infants with this disorder have been identified worldwide. </s>


Input: What are the genetic changes related to alveolar capillary dysplasia with misalignment of pulmonary veins ?

Output: ACD/MPV can be caused by mutations in the FOXF1 gene. The protein produced from the FOXF1 gene is a transcription factor, which means that it attaches (binds) to specific regions of DNA and helps control the activity of many other genes. The FOXF1 protein is important in development of the lungs and their blood vessels. The FOXF1 protein is also involved in the development of the gastrointestinal tract. Mutations in the FOXF1 gene that cause ACD/MPV result in an inactive protein that cannot regulate development, leading to abnormal formation of the pulmonary blood vessels and gastrointestinal tract.  ACD/MPV can also be caused by a deletion of genetic material on the long arm of chromosome 16 in a region known as 16q24.1. This region includes several genes, including the FOXF1 gene. Deletion of one copy of the FOXF1 gene in each cell reduces the production of the FOXF1 protein. A shortage of FOXF1 protein affects the development of pulmonary blood vessels and causes the main features of ACD/MPV. Researchers suggest that the loss of other genes in this region probably causes the additional abnormalities, such as heart defects, seen in some infants with this disorder. Like FOXF1, these genes also provide instructions for making transcription factors that regulate development of various body systems before birth.  In about 60 percent of affected infants, the genetic cause of ACD/MPV is unknown. </s>


Input: Is alveolar capillary dysplasia with misalignment of pulmonary veins inherited ?

Output: ACD/MPV is usually not inherited, and most affected people have no history of the disorder in their family. The genetic changes associated with this condition usually occur during the formation of reproductive cells (eggs and sperm) or in early fetal development. When the condition is caused by a FOXF1 gene mutation or deletion, one altered or missing gene in each cell is sufficient to cause the disorder. Individuals with ACD/MPV do not pass the genetic change on to their children because they do not live long enough to reproduce.  A few families have been identified in which more than one sibling has ACD/MPV. It is not clear how ACD/MPV is inherited in these families because no genetic changes have been identified. </s>


Input: What are the treatments for alveolar capillary dysplasia with misalignment of pulmonary veins ?

Output: These resources address the diagnosis or management of ACD/MPV:  - Genetic Testing Registry: Alveolar capillary dysplasia with misalignment of pulmonary veins  - MedlinePlus Encyclopedia: Alveolar Abnormalities   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 </s>


Input: What is (are) diastrophic dysplasia ?

Output: Diastrophic dysplasia is a disorder of cartilage and bone development. Affected individuals have short stature with very short arms and legs. Most also have early-onset joint pain (osteoarthritis) and joint deformities called contractures, which restrict movement. These joint problems often make it difficult to walk and tend to worsen with age. Additional features of diastrophic dysplasia include an inward- and upward-turning foot (clubfoot), progressive abnormal curvature of the spine, and unusually positioned thumbs (hitchhiker thumbs). About half of infants with diastrophic dysplasia are born with an opening in the roof of the mouth (a cleft palate). Swelling of the external ears is also common in newborns and can lead to thickened, deformed ears.  The signs and symptoms of diastrophic dysplasia are similar to those of another skeletal disorder called atelosteogenesis type 2; however, diastrophic dysplasia tends to be less severe. Although some affected infants have breathing problems, most people with diastrophic dysplasia live into adulthood. </s>


Input: How many people are affected by diastrophic dysplasia ?

Output: Although the exact incidence of this condition is unknown, researchers estimate that it affects about 1 in 100,000 newborns. Diastrophic dysplasia occurs in all populations but appears to be particularly common in Finland. </s>


Input: What are the genetic changes related to diastrophic dysplasia ?

Output: Diastrophic dysplasia is one of several skeletal disorders caused by mutations in the SLC26A2 gene. This gene provides instructions for making a protein that is essential for the normal development of cartilage and for its conversion to bone. Cartilage is a tough, flexible tissue that makes up much of the skeleton during early development. Most cartilage is later converted to bone, except for the cartilage that continues to cover and protect the ends of bones and is present in the nose and external ears. Mutations in the SLC26A2 gene alter the structure of developing cartilage, preventing bones from forming properly and resulting in the skeletal problems characteristic of diastrophic dysplasia. </s>


Input: Is diastrophic dysplasia inherited ?

Output: 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. </s>


Input: What are the treatments for diastrophic dysplasia ?

Output: These resources address the diagnosis or management of diastrophic dysplasia:  - Gene Review: Gene Review: Diastrophic Dysplasia  - Genetic Testing Registry: Diastrophic dysplasia   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 </s>


Input: What is (are) primary carnitine deficiency ?

Output: Primary carnitine deficiency is a condition that prevents the body from using certain fats for energy, particularly during periods without food (fasting). Carnitine, a natural substance acquired mostly through the diet, is used by cells to process fats and produce energy.  Signs and symptoms of primary carnitine deficiency typically appear during infancy or early childhood and can include severe brain dysfunction (encephalopathy), a weakened and enlarged heart (cardiomyopathy), confusion, vomiting, muscle weakness, and low blood sugar (hypoglycemia). The severity of this condition varies among affected individuals. Some people with primary carnitine deficiency are asymptomatic, which means they do not have any signs or symptoms of the condition. All individuals with this disorder are at risk for heart failure, liver problems, coma, and sudden death.  Problems related to primary carnitine deficiency can be triggered by periods of fasting or by illnesses such as viral infections. This disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections. </s>


Input: How many people are affected by primary carnitine deficiency ?

Output: The incidence of primary carnitine deficiency in the general population is approximately 1 in 100,000 newborns. In Japan, this disorder affects 1 in every 40,000 newborns. </s>


Input: What are the genetic changes related to primary carnitine deficiency ?

Output: Mutations in the SLC22A5 gene cause primary carnitine deficiency. This gene provides instructions for making a protein called OCTN2 that transports carnitine into cells. Cells need carnitine to bring certain types of fats (fatty acids) into mitochondria, which are the energy-producing centers within cells. Fatty acids are a major source of energy for the heart and muscles. During periods of fasting, fatty acids are also an important energy source for the liver and other tissues.  Mutations in the SLC22A5 gene result in an absent or dysfunctional OCTN2 protein. As a result, there is a shortage (deficiency) of carnitine within cells. Without carnitine, fatty acids cannot enter mitochondria and be used to make energy. Reduced energy production can lead to some of the features of primary carnitine deficiency, such as muscle weakness and hypoglycemia. Fatty acids may also build up in cells and damage the liver, heart, and muscles. This abnormal buildup causes the other signs and symptoms of the disorder. </s>


Input: Is primary carnitine deficiency inherited ?

Output: Primary carnitine deficiency is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive disorder are carriers, which means they each carry one copy of the mutated gene. Carriers of SLC22A5 gene mutations may have some signs and symptoms related to the condition. </s>


Input: What are the treatments for primary carnitine deficiency ?

Output: These resources address the diagnosis or management of primary carnitine deficiency:  - Baby's First Test  - Gene Review: Gene Review: Systemic Primary Carnitine Deficiency  - Genetic Testing Registry: Renal carnitine transport defect  - The Linus Pauling Institute: L-Carnitine   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 </s>


Input: What is (are) multiple sulfatase deficiency ?

Output: Multiple sulfatase deficiency is a condition that mainly affects the brain, skin, and skeleton. Because the signs and symptoms of multiple sulfatase deficiency vary widely, researchers have split the condition into three types: neonatal, late-infantile, and juvenile.  The neonatal type is the most severe form, with signs and symptoms appearing soon after birth. Affected individuals have deterioration of tissue in the nervous system (leukodystrophy), which can contribute to movement problems, seizures, developmental delay, and slow growth. They also have dry, scaly skin (ichthyosis) and excess hair growth (hypertrichosis). Skeletal abnormalities can include abnormal side-to-side curvature of the spine (scoliosis), joint stiffness, and dysostosis multiplex, which refers to a specific pattern of skeletal abnormalities seen on x-ray. Individuals with the neonatal type typically have facial features that can be described as "coarse." Affected individuals may also have hearing loss, heart malformations, and an enlarged liver and spleen (hepatosplenomegaly). Many of the signs and symptoms of neonatal multiple sulfatase deficiency worsen over time.  The late-infantile type is the most common form of multiple sulfatase deficiency. It is characterized by normal cognitive development in early childhood followed by a progressive loss of mental abilities and movement (psychomotor regression) due to leukodystrophy or other brain abnormalities. Individuals with this form of the condition do not have as many features as those with the neonatal type, but they often have ichthyosis, skeletal abnormalities, and coarse facial features.  The juvenile type is the rarest form of multiple sulfatase deficiency. Signs and symptoms of the juvenile type appear in mid- to late childhood. Affected individuals have normal early cognitive development but then experience psychomotor regression; however, the regression in the juvenile type usually occurs at a slower rate than in the late-infantile type. Ichthyosis is also common in the juvenile type of multiple sulfatase deficiency.  Life expectancy is shortened in individuals with all types of multiple sulfatase deficiency. Typically, affected individuals survive only a few years after the signs and symptoms of the condition appear, but life expectancy varies depending on the severity of the condition and how quickly the neurological problems worsen. </s>


Input: How many people are affected by multiple sulfatase deficiency ?

Output: Multiple sulfatase deficiency is estimated to occur in 1 per million individuals worldwide. Approximately 50 cases have been reported in the scientific literature. </s>


Input: What are the genetic changes related to multiple sulfatase deficiency ?

Output: Multiple sulfatase deficiency is caused by mutations in the SUMF1 gene. This gene provides instructions for making an enzyme called formylglycine-generating enzyme (FGE). This enzyme is found in a cell structure called the endoplasmic reticulum, which is involved in protein processing and transport. The FGE enzyme modifies other enzymes called sulfatases, which aid in breaking down substances that contain chemical groups known as sulfates. These substances include a variety of sugars, fats, and hormones.  Most SUMF1 gene mutations severely reduce the function of the FGE enzyme or lead to the production of an unstable enzyme that is quickly broken down. The activity of multiple sulfatases is impaired because the FGE enzyme modifies all known sulfatase enzymes. Sulfate-containing molecules that are not broken down build up in cells, often resulting in cell death. The death of cells in particular tissues, specifically the brain, skeleton, and skin, cause many of the signs and symptoms of multiple sulfatase deficiency.  Research indicates that mutations that lead to reduced FGE enzyme function are associated with the less severe cases of the condition, whereas mutations that lead to the production of an unstable FGE enzyme tend to be associated with the more severe cases of multiple sulfatase deficiency. </s>


Input: Is multiple sulfatase deficiency inherited ?

Output: 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. </s>


Input: What are the treatments for multiple sulfatase deficiency ?

Output: These resources address the diagnosis or management of multiple sulfatase deficiency:  - Genetic Testing Registry: Multiple sulfatase 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 </s>


Input: What is (are) inclusion body myopathy 2 ?

Output: Inclusion body myopathy 2 is a condition that primarily affects skeletal muscles, which are muscles that the body uses for movement. This disorder causes muscle weakness that appears in late adolescence or early adulthood and worsens over time.  The first sign of inclusion body myopathy 2 is weakness of a muscle in the lower leg called the tibialis anterior. This muscle helps control up-and-down movement of the foot. Weakness in the tibialis anterior alters the way a person walks and makes it difficult to run and climb stairs. As the disorder progresses, weakness also develops in muscles of the upper legs, hips, shoulders, and hands. Unlike most forms of myopathy, inclusion body myopathy 2 usually does not affect the quadriceps, which are a group of large muscles at the front of the thigh. This condition also does not affect muscles of the eye or heart, and it does not cause neurological problems. Weakness in leg muscles makes walking increasingly difficult, and most people with inclusion body myopathy 2 require wheelchair assistance within 20 years after signs and symptoms appear.  People with the characteristic features of inclusion body myopathy 2 have been described in several different populations. When the condition was first reported in Japanese families, researchers called it distal myopathy with rimmed vacuoles (DMRV) or Nonaka myopathy. When a similar disorder was discovered in Iranian Jewish families, researchers called it rimmed vacuole myopathy or hereditary inclusion body myopathy (HIBM). It has since become clear that these conditions are variations of a single disorder caused by mutations in the same gene. </s>


Input: How many people are affected by inclusion body myopathy 2 ?

Output: More than 200 people with inclusion body myopathy 2 have been reported. Most are of Iranian Jewish descent; the condition affects an estimated 1 in 1,500 people in this population. Additionally, at least 15 people in the Japanese population have been diagnosed with this disorder. Inclusion body myopathy 2 has also been found in several other ethnic groups worldwide. </s>


Input: What are the genetic changes related to inclusion body myopathy 2 ?

Output: Mutations in the GNE gene cause inclusion body myopathy 2. The GNE gene provides instructions for making an enzyme found in cells and tissues throughout the body. This enzyme is involved in a chemical pathway that produces sialic acid, which is a simple sugar that attaches to the ends of more complex molecules on the surface of cells. By modifying these molecules, sialic acid influences a wide variety of cellular functions including cell movement (migration), attaching cells to one another (adhesion), signaling between cells, and inflammation.  The mutations responsible for inclusion body myopathy 2 reduce the activity of the enzyme produced from the GNE gene, which decreases the production of sialic acid. As a result, less of this simple sugar is available to attach to cell surface molecules. Researchers are working to determine how a shortage of sialic acid leads to progressive muscle weakness in people with inclusion body myopathy 2. Sialic acid is important for the normal function of many different cells and tissues, so it is unclear why the signs and symptoms of this disorder appear to be limited to the skeletal muscles. </s>


Input: Is inclusion body myopathy 2 inherited ?

Output: 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. </s>


Input: What are the treatments for inclusion body myopathy 2 ?

Output: These resources address the diagnosis or management of inclusion body myopathy 2:  - Gene Review: Gene Review: GNE-Related Myopathy  - Genetic Testing Registry: Inclusion body myopathy 2  - Genetic Testing Registry: Nonaka myopathy   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 </s>


Input: What is (are) lactate dehydrogenase deficiency ?

Output: Lactate dehydrogenase deficiency is a condition that affects how the body breaks down sugar to use as energy in cells, primarily muscle cells.  There are two types of this condition: lactate dehydrogenase-A deficiency (sometimes called glycogen storage disease XI) and lactate dehydrogenase-B deficiency.  People with lactate dehydrogenase-A deficiency experience fatigue, muscle pain, and cramps during exercise (exercise intolerance). In some people with lactate dehydrogenase-A deficiency, high-intensity exercise or other strenuous activity leads to the breakdown of muscle tissue (rhabdomyolysis). The destruction of muscle tissue releases a protein called myoglobin, which is processed by the kidneys and released in the urine (myoglobinuria). Myoglobin causes the urine to be red or brown. This protein can also damage the kidneys, in some cases leading to life-threatening kidney failure. Some people with lactate dehydrogenase-A deficiency develop skin rashes. The severity of the signs and symptoms among individuals with lactate dehydrogenase-A deficiency varies greatly.  People with lactate dehydrogenase-B deficiency typically do not have any signs or symptoms of the condition. They do not have difficulty with physical activity or any specific physical features related to the condition. Affected individuals are usually discovered only when routine blood tests reveal reduced lactate dehydrogenase activity. </s>


Input: How many people are affected by lactate dehydrogenase deficiency ?

Output: Lactate dehydrogenase deficiency is a rare disorder. In Japan, this condition affects 1 in 1 million individuals; the prevalence of lactate dehydrogenase deficiency in other countries is unknown. </s>


Input: What are the genetic changes related to lactate dehydrogenase deficiency ?

Output: Mutations in the LDHA gene cause lactate dehydrogenase-A deficiency, and mutations in the LDHB gene cause lactate dehydrogenase-B deficiency. These genes provide instructions for making the lactate dehydrogenase-A and lactate dehydrogenase-B pieces (subunits) of the lactate dehydrogenase enzyme. This enzyme is found throughout the body and is important for creating energy for cells. There are five different forms of this enzyme, each made up of four protein subunits. Various combinations of the lactate dehydrogenase-A and lactate dehydrogenase-B subunits make up the different forms of the enzyme.  The version of lactate dehydrogenase made of four lactate dehydrogenase-A subunits is found primarily in skeletal muscles, which are muscles used for movement. Skeletal muscles need large amounts of energy during high-intensity physical activity when the body's oxygen intake is not sufficient for the amount of energy required (anaerobic exercise). During anaerobic exercise, the lactate dehydrogenase enzyme is involved in the breakdown of sugar stored in the muscles (in the form of glycogen) to create additional energy. During the final stage of glycogen breakdown, lactate dehydrogenase converts a molecule called pyruvate to a similar molecule called lactate.  Mutations in the LDHA gene result in the production of an abnormal lactate dehydrogenase-A subunit that cannot attach (bind) to other subunits to form the lactate dehydrogenase enzyme. A lack of functional subunit reduces the amount of enzyme that is formed, mostly affecting skeletal muscles. As a result, glycogen is not broken down efficiently, leading to decreased energy in muscle cells. When muscle cells do not get sufficient energy during exercise or strenuous activity, the muscles become weak and muscle tissue can break down, as experienced by people with lactate dehydrogenase-A deficiency.  The version of lactate dehydrogenase made of four lactate dehydrogenase-B subunits is found primarily in heart (cardiac) muscle. In cardiac muscle, lactate dehydrogenase converts lactate to pyruvate, which can participate in other chemical reactions to create energy. LDHB gene mutations lead to the production of an abnormal lactate dehydrogenase-B subunit that cannot form the lactate dehydrogenase enzyme. Even though lactate dehydrogenase activity is decreased in the cardiac muscle of people with lactate dehydrogenase-B deficiency, they do not appear to have any signs or symptoms related to their condition. It is unclear why this type of enzyme deficiency does not cause any health problems. </s>


Input: Is lactate dehydrogenase deficiency inherited ?

Output: 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. </s>


Input: What are the treatments for lactate dehydrogenase deficiency ?

Output: These resources address the diagnosis or management of lactate dehydrogenase deficiency:  - Genetic Testing Registry: Glycogen storage disease XI  - Genetic Testing Registry: Lactate dehydrogenase B deficiency  - MedlinePlus Encyclopedia: LDH Isoenzymes  - MedlinePlus Encyclopedia: Lactate Dehydrogenase Test   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 </s>


Input: What is (are) Kallmann syndrome ?

Output: Kallmann syndrome is a condition characterized by delayed or absent puberty and an impaired sense of smell.  This disorder is a form of hypogonadotropic hypogonadism (HH), which is a condition affecting the production of hormones that direct sexual development. Males with hypogonadotropic hypogonadism are often born with an unusually small penis (micropenis) and undescended testes (cryptorchidism). At puberty, most affected individuals do not develop secondary sex characteristics, such as the growth of facial hair and deepening of the voice in males. Affected females usually do not begin menstruating at puberty and have little or no breast development. In some people, puberty is incomplete or delayed.  In Kallmann syndrome, the sense of smell is either diminished (hyposmia) or completely absent (anosmia). This feature distinguishes Kallmann syndrome from most other forms of hypogonadotropic hypogonadism, which do not affect the sense of smell. Many people with Kallmann syndrome are not aware that they are unable to detect odors until the impairment is discovered through testing.  The features of Kallmann syndrome vary, even among affected people in the same family. Additional signs and symptoms can include a failure of one kidney to develop (unilateral renal agenesis), a cleft lip with or without an opening in the roof of the mouth (a cleft palate), abnormal eye movements, hearing loss, and abnormalities of tooth development. Some affected individuals have a condition called bimanual synkinesis, in which the movements of one hand are mirrored by the other hand. Bimanual synkinesis can make it difficult to do tasks that require the hands to move separately, such as playing a musical instrument.  Researchers have identified four forms of Kallmann syndrome, designated types 1 through 4, which are distinguished by their genetic cause. The four types are each characterized by hypogonadotropic hypogonadism and an impaired sense of smell. Additional features, such as a cleft palate, seem to occur only in types 1 and 2. </s>


Input: How many people are affected by Kallmann syndrome ?

Output: Kallmann syndrome is estimated to affect 1 in 10,000 to 86,000 people and occurs more often in males than in females. Kallmann syndrome 1 is the most common form of the disorder. </s>


Input: What are the genetic changes related to Kallmann syndrome ?

Output: Mutations in the ANOS1, FGFR1, PROKR2, and PROK2 genes cause Kallmann syndrome. ANOS1 gene mutations are responsible for Kallmann syndrome 1. Kallmann syndrome 2 results from mutations in the FGFR1 gene. Mutations in the PROKR2 and PROK2 genes cause Kallmann syndrome types 3 and 4, respectively.  The genes associated with Kallmann syndrome play a role in the development of certain areas of the brain before birth. Although some of their specific functions are unclear, these genes appear to be involved in the formation and movement (migration) of a group of nerve cells that are specialized to process smells (olfactory neurons). These nerve cells come together into a bundle called the olfactory bulb, which is critical for the perception of odors. The ANOS1, FGFR1, PROKR2, and PROK2 genes also play a role in the migration of neurons that produce a hormone called gonadotropin-releasing hormone (GnRH). GnRH controls the production of several other hormones that direct sexual development before birth and during puberty. These hormones are important for the normal function of the gonads (ovaries in women and testes in men).  Studies suggest that mutations in the ANOS1, FGFR1, PROKR2, or PROK2 gene disrupt the migration of olfactory nerve cells and GnRH-producing nerve cells in the developing brain. If olfactory nerve cells do not extend to the olfactory bulb, a person's sense of smell will be impaired or absent. Misplacement of GnRH-producing neurons prevents the production of certain sex hormones, which interferes with normal sexual development and causes the characteristic features of hypogonadotropic hypogonadism. It is unclear how gene mutations lead to the other possible signs and symptoms of Kallmann syndrome. Because the features of this condition vary among individuals, researchers suspect that additional genetic and environmental factors may be involved.  Together, mutations in the ANOS1, FGFR1, PROKR2, and PROK2 genes account for 25 percent to 30 percent of all cases of Kallmann syndrome. In cases without an identified mutation in one of these genes, the cause of the condition is unknown. Researchers are looking for other genes that can cause this disorder. </s>


Input: Is Kallmann syndrome inherited ?

Output: Kallmann syndrome 1 (caused by ANOS1 gene mutations) has an X-linked recessive pattern of inheritance. The ANOS1 gene 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 must be present in both copies of the gene to cause the disorder. 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.  Most cases of Kallmann syndrome 1 are described as simplex, which means only one person in a family is affected. Some affected people inherit a ANOS1 gene mutation from their mothers, who carry a single mutated copy of the gene in each cell. Other people have the condition as a result of a new mutation in the ANOS1 gene.  Other forms of Kallmann syndrome can be 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.  In several families, Kallmann syndrome has shown an autosomal recessive pattern of inheritance. Autosomal recessive inheritance 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. </s>


Input: What are the treatments for Kallmann syndrome ?

Output: These resources address the diagnosis or management of Kallmann syndrome:  - Gene Review: Gene Review: Isolated Gonadotropin-Releasing Hormone (GnRH) Deficiency  - Genetic Testing Registry: Hypogonadism with anosmia  - Genetic Testing Registry: Kallmann syndrome 1  - Genetic Testing Registry: Kallmann syndrome 2  - Genetic Testing Registry: Kallmann syndrome 3  - Genetic Testing Registry: Kallmann syndrome 4  - MedlinePlus Encyclopedia: Hypogonadotropic Hypogonadism  - MedlinePlus Encyclopedia: Smell - Impaired   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 </s>


Input: What is (are) Bardet-Biedl syndrome ?

Output: Bardet-Biedl syndrome is a disorder that affects many parts of the body. The signs and symptoms of this condition vary among affected individuals, even among members of the same family.  Vision loss is one of the major features of Bardet-Biedl syndrome. Loss of vision occurs as the light-sensing tissue at the back of the eye (the retina) gradually deteriorates. Problems with night vision become apparent by mid-childhood, followed by blind spots that develop in the side (peripheral) vision. Over time, these blind spots enlarge and merge to produce tunnel vision. Most people with Bardet-Biedl syndrome also develop blurred central vision (poor visual acuity) and become legally blind by adolescence or early adulthood.  Obesity is another characteristic feature of Bardet-Biedl syndrome. Abnormal weight gain typically begins in early childhood and continues to be an issue throughout life. Complications of obesity can include type 2 diabetes, high blood pressure (hypertension), and abnormally high cholesterol levels (hypercholesterolemia).  Other major signs and symptoms of Bardet-Biedl syndrome include the presence of extra fingers or toes (polydactyly), intellectual disability or learning problems, and abnormalities of the genitalia. Most affected males produce reduced amounts of sex hormones (hypogonadism), and they are usually unable to father biological children (infertile). Many people with Bardet-Biedl syndrome also have kidney abnormalities, which can be serious or life-threatening.  Additional features of Bardet-Biedl syndrome can include impaired speech, delayed development of motor skills such as standing and walking, behavioral problems such as emotional immaturity and inappropriate outbursts, and clumsiness or poor coordination. Distinctive facial features, dental abnormalities, unusually short or fused fingers or toes, and a partial or complete loss of the sense of smell (anosmia) have also been reported in some people with Bardet-Biedl syndrome. Additionally, this condition can affect the heart, liver, and digestive system. </s>


Input: How many people are affected by Bardet-Biedl syndrome ?

Output: In most of North America and Europe, Bardet-Biedl syndrome has a prevalence of 1 in 140,000 to 1 in 160,000 newborns. The condition is more common on the island of Newfoundland (off the east coast of Canada), where it affects an estimated 1 in 17,000 newborns. It also occurs more frequently in the Bedouin population of Kuwait, affecting about 1 in 13,500 newborns. </s>


Input: What are the genetic changes related to Bardet-Biedl syndrome ?

Output: Bardet-Biedl syndrome can result from mutations in at least 14 different genes (often called BBS genes). These genes are known or suspected to play critical roles in cell structures called cilia. Cilia are microscopic, finger-like projections that stick out from the surface of many types of cells. They are involved in cell movement and many different chemical signaling pathways. Cilia are also necessary for the perception of sensory input (such as sight, hearing, and smell). The proteins produced from BBS genes are involved in the maintenance and function of cilia.  Mutations in BBS genes lead to problems with the structure and function of cilia. Defects in these cell structures probably disrupt important chemical signaling pathways during development and lead to abnormalities of sensory perception. Researchers believe that defective cilia are responsible for most of the features of Bardet-Biedl syndrome.  About one-quarter of all cases of Bardet-Biedl syndrome result from mutations in the BBS1 gene. Another 20 percent of cases are caused by mutations in the BBS10 gene. The other BBS genes each account for only a small percentage of all cases of this condition. In about 25 percent of people with Bardet-Biedl syndrome, the cause of the disorder is unknown.  In affected individuals who have mutations in one of the BBS genes, mutations in additional genes may be involved in causing or modifying the course of the disorder. Studies suggest that these modifying genes may be known BBS genes or other genes. The additional genetic changes could help explain the variability in the signs and symptoms of Bardet-Biedl syndrome. However, this phenomenon appears to be uncommon, and it has not been found consistently in scientific studies. </s>


Input: Is Bardet-Biedl syndrome inherited ?

Output: Bardet-Biedl syndrome is typically inherited in an autosomal recessive pattern, which means both copies of a BBS 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. </s>


Input: What are the treatments for Bardet-Biedl syndrome ?

Output: These resources address the diagnosis or management of Bardet-Biedl syndrome:  - Gene Review: Gene Review: Bardet-Biedl Syndrome  - Genetic Testing Registry: Bardet-Biedl syndrome  - MedlinePlus Encyclopedia: Obesity  - MedlinePlus Encyclopedia: Polydactyly   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 </s>


Input: What is (are) 3-beta-hydroxysteroid dehydrogenase deficiency ?

Output: 3-beta ()-hydroxysteroid dehydrogenase (HSD) deficiency is an inherited disorder that affects hormone-producing glands including the gonads (ovaries in females and testes in males) and the adrenal glands. The gonads direct sexual development before birth and during puberty. The adrenal glands, which are located on top of the kidneys, regulate the production of certain hormones and control salt levels in the body. People with 3-HSD deficiency lack many of the hormones that are made in these glands. 3-HSD deficiency is one of a group of disorders known as congenital adrenal hyperplasias that impair hormone production and disrupt sexual development and maturation.  There are three types of 3-HSD deficiency: the salt-wasting, non-salt-wasting, and non-classic types. In the salt-wasting type, hormone production is extremely low. Individuals with this type lose large amounts of sodium in their urine, which can be life-threatening. Individuals affected with the salt-wasting type are usually diagnosed soon after birth due to complications related to a lack of salt reabsorption, including dehydration, poor feeding, and vomiting. People with the non-salt-wasting type of 3-HSD deficiency produce enough hormone to allow sodium reabsorption in the kidneys. Individuals with the non-classic type have the mildest symptoms and do not experience salt wasting.  In males with any type of 3-HSD deficiency, problems with male sex hormones lead to abnormalities of the external genitalia. These abnormalities range from having the opening of the urethra on the underside of the penis (hypospadias) to having external genitalia that do not look clearly male or female (ambiguous genitalia). The severity of the genital abnormality does not consistently depend on the type of the condition. Because of the hormone dysfunction in the testes, males with 3-HSD deficiency are frequently unable to have biological children (infertile).  Females with 3-HSD deficiency may have slight abnormalities of the external genitalia at birth. Females affected with the non-salt-wasting or non-classic types are typically not diagnosed until mid-childhood or puberty, when they may experience irregular menstruation, premature pubic hair growth, and excessive body hair growth (hirsutism). Females with 3-HSD deficiency have difficulty conceiving a child (impaired fertility). </s>


Input: How many people are affected by 3-beta-hydroxysteroid dehydrogenase deficiency ?

Output: The exact prevalence of 3-HSD deficiency is unknown. At least 60 affected individuals have been reported. </s>


Input: What are the genetic changes related to 3-beta-hydroxysteroid dehydrogenase deficiency ?

Output: Mutations in the HSD3B2 gene cause 3-HSD deficiency. The HSD3B2 gene provides instructions for making the 3-HSD enzyme. This enzyme is found in the gonads and adrenal glands. The 3-HSD enzyme is involved in the production of many hormones, including cortisol, aldosterone, androgens, and estrogen. Cortisol has numerous functions such as maintaining energy and blood sugar levels, protecting the body from stress, and suppressing inflammation. Aldosterone is sometimes called the salt-retaining hormone because it regulates the amount of salt retained by the kidney. The retention of salt affects fluid levels and blood pressure. Androgens and estrogen are essential for normal sexual development and reproduction.  3-HSD deficiency is caused by a deficiency (shortage) of the 3-HSD enzyme. The amount of functional 3-HSD enzyme determines whether a person will have the salt-wasting or non-salt-wasting type of the disorder. Individuals with the salt-wasting type have HSD3B2 gene mutations that result in the production of very little or no enzyme. People with the non-salt-wasting type of this condition have HSD3B2 gene mutations that allow the production of some functional enzyme, although in reduced amounts. </s>


Input: Is 3-beta-hydroxysteroid dehydrogenase deficiency inherited ?

Output: 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. </s>


Input: What are the treatments for 3-beta-hydroxysteroid dehydrogenase deficiency ?

Output: These resources address the diagnosis or management of 3-beta-hydroxysteroid dehydrogenase deficiency:  - Genetic Testing Registry: 3 beta-Hydroxysteroid dehydrogenase deficiency  - Great Ormond Street Hospital for Children: Cortisol Deficiency  - MedlinePlus Encyclopedia: Ambiguous Genitalia  - MedlinePlus Encyclopedia: Congenital Adrenal Hyperplasia  - MedlinePlus Health Topic: Assisted Reproductive Technology  - National Institutes of Health Clinical Center: Managing Adrenal Insufficiency   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 </s>


Input: What is (are) popliteal pterygium syndrome ?

Output: Popliteal pterygium syndrome is a condition that affects the development of the face, skin, and genitals. Most people with this disorder are born with a cleft lip, a cleft palate (an opening in the roof of the mouth), or both. Affected individuals may have depressions (pits) near the center of the lower lip, which may appear moist due to the presence of salivary and mucous glands in the pits. Small mounds of tissue on the lower lip may also occur. In some cases, people with popliteal pterygium syndrome have missing teeth.  Individuals with popliteal pterygium syndrome may be born with webs of skin on the backs of the legs across the knee joint, which may impair mobility unless surgically removed. Affected individuals may also have webbing or fusion of the fingers or toes (syndactyly), characteristic triangular folds of skin over the nails of the large toes, or tissue connecting the upper and lower eyelids or the upper and lower jaws. They may have abnormal genitals, including unusually small external genital folds (hypoplasia of the labia majora) in females. Affected males may have undescended testes (cryptorchidism) or a scrotum divided into two lobes (bifid scrotum).  People with popliteal pterygium syndrome who have cleft lip and/or palate, like other individuals with these facial conditions, may have an increased risk of delayed language development, learning disabilities, or other mild cognitive problems. The average IQ of individuals with popliteal pterygium syndrome is not significantly different from that of the general population. </s>


Input: How many people are affected by popliteal pterygium syndrome ?

Output: Popliteal pterygium syndrome is a rare condition, occurring in approximately 1 in 300,000 individuals. </s>


Input: What are the genetic changes related to popliteal pterygium syndrome ?

Output: Mutations in the IRF6 gene cause popliteal pterygium syndrome. The IRF6 gene provides instructions for making a protein that plays an important role in early development. This protein is a transcription factor, which means that it attaches (binds) to specific regions of DNA and helps control the activity of particular genes.  The IRF6 protein is active in cells that give rise to tissues in the head and face. It is also involved in the development of other parts of the body, including the skin and genitals.  Mutations in the IRF6 gene that cause popliteal pterygium syndrome may change the transcription factor's effect on the activity of certain genes. This affects the development and maturation of tissues in the face, skin, and genitals, resulting in the signs and symptoms of popliteal pterygium syndrome. </s>


Input: Is popliteal pterygium syndrome inherited ?

Output: 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. </s>


Input: What are the treatments for popliteal pterygium syndrome ?

Output: These resources address the diagnosis or management of popliteal pterygium syndrome:  - Gene Review: Gene Review: IRF6-Related Disorders  - Genetic Testing Registry: Popliteal pterygium 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 </s>


Input: What is (are) white sponge nevus ?

Output: White sponge nevus is a condition characterized by the formation of white patches of tissue called nevi (singular: nevus) that appear as thickened, velvety, sponge-like tissue. The nevi are most commonly found on the moist lining of the mouth (oral mucosa), especially on the inside of the cheeks (buccal mucosa). Affected individuals usually develop multiple nevi. Rarely, white sponge nevi also occur on the mucosae (singular: mucosa) of the nose, esophagus, genitals, or anus. The nevi are caused by a noncancerous (benign) overgrowth of cells.  White sponge nevus can be present from birth but usually first appears during early childhood. The size and location of the nevi can change over time. In the oral mucosa, both sides of the mouth are usually affected. The nevi are generally painless, but the folds of extra tissue can promote bacterial growth, which can lead to infection that may cause discomfort. The altered texture and appearance of the affected tissue, especially the oral mucosa, can be bothersome for some affected individuals. </s>


Input: How many people are affected by white sponge nevus ?

Output: The exact prevalence of white sponge nevus is unknown, but it is estimated to affect less than 1 in 200,000 individuals worldwide. </s>


Input: What are the genetic changes related to white sponge nevus ?

Output: Mutations in the KRT4 or KRT13 gene cause white sponge nevus. These genes provide instructions for making proteins called keratins. Keratins are a group of tough, fibrous proteins that form the structural framework of epithelial cells, which are cells that line the surfaces and cavities of the body and make up the different mucosae. The keratin 4 protein (produced from the KRT4 gene) and the keratin 13 protein (produced from the KRT13 gene) partner together to form molecules known as intermediate filaments. These filaments assemble into networks that provide strength and resilience to the different mucosae. Networks of intermediate filaments protect the mucosae from being damaged by friction or other everyday physical stresses.  Mutations in the KRT4 or KRT13 gene disrupt the structure of the keratin protein. As a result, keratin 4 and keratin 13 are mismatched and do not fit together properly, leading to the formation of irregular intermediate filaments that are easily damaged with little friction or trauma. Fragile intermediate filaments in the oral mucosa might be damaged when eating or brushing one's teeth. Damage to intermediate filaments leads to inflammation and promotes the abnormal growth and division (proliferation) of epithelial cells, causing the mucosae to thicken and resulting in white sponge nevus. </s>


Input: Is white sponge nevus inherited ?

Output: This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell can be sufficient to cause the disorder. However, some people who have a mutation that causes white sponge nevus do not develop these abnormal growths; this phenomenon is called reduced penetrance. </s>


Input: What are the treatments for white sponge nevus ?

Output: These resources address the diagnosis or management of white sponge nevus:  - Genetic Testing Registry: White sponge nevus of cannon   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 </s>


Input: What is (are) Maffucci syndrome ?

Output: Maffucci syndrome is a disorder that primarily affects the bones and skin. It is characterized by multiple enchondromas, which are noncancerous (benign) growths of cartilage that develop within the bones. These growths most commonly occur in the limb bones, especially in the bones of the hands and feet; however, they may also occur in the skull, ribs, and bones of the spine (vertebrae). Enchondromas may result in severe bone deformities, shortening of the limbs, and fractures.  The signs and symptoms of Maffucci syndrome may be detectable at birth, although they generally do not become apparent until around the age of 5. Enchondromas develop near the ends of bones, where normal growth occurs, and they frequently stop forming after affected individuals stop growing in early adulthood. As a result of the bone deformities associated with Maffucci syndrome, people with this disorder generally have short stature and underdeveloped muscles.  Maffucci syndrome is distinguished from a similar disorder that involves enchondromas (Ollier disease) by the presence of red or purplish growths in the skin consisting of tangles of abnormal blood vessels (hemangiomas). In addition to hemangiomas, individuals with Maffucci syndrome occasionally also have lymphangiomas, which are masses made up of the thin tubes that carry lymph fluid (lymphatic vessels). These growths may appear anywhere on the body.  Although the enchondromas associated with Maffucci syndrome start out as benign, they may become cancerous (malignant). In particular, affected individuals may develop bone cancers called chondrosarcomas, especially in the skull. People with Maffucci syndrome also have an increased risk of other cancers, such as ovarian or liver cancer.  People with Maffucci syndrome usually have a normal lifespan, and intelligence is unaffected. The extent of their physical impairment depends on their individual skeletal deformities, but in most cases they have no major limitations in their activities. </s>


Input: How many people are affected by Maffucci syndrome ?

Output: Maffucci syndrome is very rare. Since it was first described in 1881, fewer than 200 cases have been reported worldwide. </s>


Input: What are the genetic changes related to Maffucci syndrome ?

Output: In most people with Maffucci syndrome, the disorder is caused by mutations in the IDH1 or IDH2 gene. These genes provide instructions for making enzymes called isocitrate dehydrogenase 1 and isocitrate dehydrogenase 2, respectively. These enzymes convert a compound called isocitrate to another compound called 2-ketoglutarate. This reaction also produces a molecule called NADPH, which is necessary for many cellular processes. IDH1 or IDH2 gene mutations cause the enzyme produced from the respective gene to take on a new, abnormal function. Although these mutations have been found in some cells of enchondromas and hemangiomas in people with Maffucci syndrome, the relationship between the mutations and the signs and symptoms of the disorder is not well understood.  Mutations in other genes may also account for some cases of Maffucci syndrome. </s>


Input: Is Maffucci syndrome inherited ?

Output: Maffucci syndrome is not inherited. The mutations that cause this disorder are somatic, which means they occur during a person's lifetime. A somatic mutation occurs in a single cell. As that cell continues to grow and divide, the cells derived from it also have the same mutation. In Maffucci syndrome, the mutation is thought to occur in a cell during early development before birth; cells that arise from that abnormal cell have the mutation, while the body's other cells do not. This situation is called mosaicism. </s>


Input: What are the treatments for Maffucci syndrome ?

Output: These resources address the diagnosis or management of Maffucci syndrome:  - Genetic Testing Registry: Maffucci 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 </s>


Input: What is (are) hereditary antithrombin deficiency ?

Output: Hereditary antithrombin deficiency is a disorder of blood clotting. People with this condition are at higher than average risk for developing abnormal blood clots, particularly a type of clot that occurs in the deep veins of the legs. This type of clot is called a deep vein thrombosis (DVT). Affected individuals also have an increased risk of developing a pulmonary embolism (PE), which is a clot that travels through the bloodstream and lodges in the lungs. In hereditary antithrombin deficiency, abnormal blood clots usually form only in veins, although they may rarely occur in arteries.  About half of people with hereditary antithrombin deficiency will develop at least one abnormal blood clot during their lifetime. These clots usually develop after adolescence.  Other factors can increase the risk of abnormal blood clots in people with hereditary antithrombin deficiency. These factors include increasing age, surgery, or immobility. The combination of hereditary antithrombin deficiency and other inherited disorders of blood clotting can also influence risk. Women with hereditary antithrombin deficiency are at increased risk of developing an abnormal blood clot during pregnancy or soon after delivery. They also may have an increased risk for pregnancy loss (miscarriage) or stillbirth. </s>


Input: How many people are affected by hereditary antithrombin deficiency ?

Output: Hereditary antithrombin deficiency is estimated to occur in about 1 in 2,000 to 3,000 individuals. Of people who have experienced an abnormal blood clot, about 1 in 20 to 200 have hereditary antithrombin deficiency. </s>


Input: What are the genetic changes related to hereditary antithrombin deficiency ?

Output: Hereditary antithrombin deficiency is caused by mutations in the SERPINC1 gene. This gene provides instructions for producing a protein called antithrombin (previously known as antithrombin III). This protein is found in the bloodstream and is important for controlling blood clotting. Antithrombin blocks the activity of proteins that promote blood clotting, especially a protein called thrombin.  Most of the mutations that cause hereditary antithrombin deficiency change single protein building blocks (amino acids) in antithrombin, which disrupts its ability to control blood clotting. Individuals with this condition do not have enough functional antithrombin to inactivate clotting proteins, which results in the increased risk of developing abnormal blood clots. </s>


Input: Is hereditary antithrombin deficiency inherited ?

Output: Hereditary antithrombin deficiency is typically inherited in an autosomal dominant pattern, which means one altered copy of the SERPINC1 gene in each cell is sufficient to cause the disorder. Inheriting two altered copies of this gene in each cell is usually incompatible with life; however, a few severely affected individuals have been reported with mutations in both copies of the SERPINC1 gene in each cell. </s>


Input: What are the treatments for hereditary antithrombin deficiency ?

Output: These resources address the diagnosis or management of hereditary antithrombin deficiency:  - Genetic Testing Registry: Antithrombin III deficiency  - MedlinePlus Encyclopedia: Blood Clots  - MedlinePlus Encyclopedia: Congenital Antithrombin III 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 </s>


Input: What is (are) glycogen storage disease type V ?

Output: Glycogen storage disease type V (also known as GSDV or McArdle disease) is an inherited disorder caused by an inability to break down a complex sugar called glycogen in muscle cells. A lack of glycogen breakdown interferes with the function of muscle cells.  People with GSDV typically experience fatigue, muscle pain, and cramps during the first few minutes of exercise (exercise intolerance). Exercise such as weight lifting or jogging usually triggers these symptoms in affected individuals. The discomfort is generally alleviated with rest. If individuals rest after brief exercise and wait for their pain to go away, they can usually resume exercising with little or no discomfort (a characteristic phenomenon known as "second wind").  Prolonged or intense exercise can cause muscle damage in people with GSDV. About half of people with GSDV experience breakdown of muscle tissue (rhabdomyolysis). In severe episodes, the destruction of muscle tissue releases a protein called myoglobin, which is filtered through the kidneys and released in the urine (myoglobinuria). Myoglobin causes the urine to be red or brown. This protein can also damage the kidneys, and it is estimated that half of those individuals with GSDV who have myoglobinuria will develop life-threatening kidney failure.  The signs and symptoms of GSDV can vary significantly in affected individuals. The features of this condition typically begin in a person's teens or twenties, but they can appear anytime from infancy to adulthood. In most people with GSDV, the muscle weakness worsens over time; however, in about one-third of affected individuals, the muscle weakness is stable. Some people with GSDV experience mild symptoms such as poor stamina; others do not experience any symptoms. </s>


Input: How many people are affected by glycogen storage disease type V ?

Output: GSDV is a rare disorder; however, its prevalence is unknown. In the Dallas-Fort Worth area of Texas, where the prevalence of GSDV has been studied, the condition is estimated to affect 1 in 100,000 individuals. </s>


Input: What are the genetic changes related to glycogen storage disease type V ?

Output: Mutations in the PYGM gene cause GSDV. The PYGM gene provides instructions for making an enzyme called myophosphorylase. This enzyme is found only in muscle cells, where it breaks down glycogen into a simpler sugar called glucose-1-phosphate. Additional steps convert glucose-1-phosphate into glucose, a simple sugar that is the main energy source for most cells.  PYGM gene mutations prevent myophosphorylase from breaking down glycogen effectively. As a result, muscle cells cannot produce enough energy, so muscles become easily fatigued. Reduced energy production in muscle cells leads to the major features of GSDV. </s>


Input: Is glycogen storage disease type V inherited ?

Output: 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. </s>


Input: What are the treatments for glycogen storage disease type V ?

Output: These resources address the diagnosis or management of glycogen storage disease type V:  - Gene Review: Gene Review: Glycogen Storage Disease Type V  - Genetic Testing Registry: Glycogen storage disease, type V  - MedlinePlus Encyclopedia: McArdle 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 </s>


Input: What is (are) COL4A1-related brain small-vessel disease ?

Output: COL4A1-related brain small-vessel disease is part of a group of conditions called the COL4A1-related disorders. The conditions in this group have a range of signs and symptoms that involve fragile blood vessels. COL4A1-related brain small-vessel disease is characterized by weakening of the blood vessels in the brain. Stroke is often the first symptom of this condition, typically occurring in mid-adulthood. In affected individuals, stroke is usually caused by bleeding in the brain (hemorrhagic stroke) rather than a lack of blood flow in the brain (ischemic stroke), although either type can occur. Individuals with this condition are at increased risk of having more than one stroke in their lifetime. People with COL4A1-related brain small vessel disease also have leukoencephalopathy, which is a change in a type of brain tissue called white matter that can be seen with magnetic resonance imaging (MRI). Affected individuals may also experience seizures and migraine headaches accompanied by visual sensations known as auras.  Some people with COL4A1-related brain small-vessel disease have an eye abnormality called Axenfeld-Rieger anomaly. Axenfeld-Rieger anomaly involves underdevelopment and eventual tearing of the colored part of the eye (iris) and a pupil that is not in the center of the eye. Other eye problems experienced by people with COL4A1-related brain small-vessel disease include clouding of the lens of the eye (cataract) and the presence of arteries that twist and turn abnormally within the light-sensitive tissue at the back of the eye (arterial retinal tortuosity). Axenfeld-Rieger anomaly and cataract can cause impaired vision. Arterial retinal tortuosity can cause episodes of bleeding within the eye following any minor trauma to the eye, leading to temporary vision loss.  The severity of the condition varies greatly among affected individuals. Some individuals with COL4A1-related brain small-vessel disease do not have any signs or symptoms of the condition. </s>


Input: How many people are affected by COL4A1-related brain small-vessel disease ?

Output: COL4A1-related brain small-vessel disease is a rare condition, although the exact prevalence is unknown. At least 50 individuals with this condition have been described in the scientific literature. </s>


Input: What are the genetic changes related to COL4A1-related brain small-vessel disease ?

Output: As the name suggests, mutations in the COL4A1 gene cause COL4A1-related brain small vessel disease. The COL4A1 gene provides instructions for making one component of a protein called type IV collagen. Type IV collagen molecules attach to each other to form complex protein networks. These protein networks are the main components of basement membranes, which are thin sheet-like structures that separate and support cells in many tissues. Type IV collagen networks play an important role in the basement membranes in virtually all tissues throughout the body, particularly the basement membranes surrounding the body's blood vessels (vasculature).  The COL4A1 gene mutations that cause COL4A1-related brain small-vessel disease result in the production of a protein that disrupts the structure of type IV collagen. As a result, type IV collagen molecules cannot attach to each other to form the protein networks in basement membranes. Basement membranes without these networks are unstable, leading to weakening of the tissues that they surround. In people with COL4A1-related brain small-vessel disease, the vasculature in the brain weakens, which can lead to blood vessel breakage and stroke. Similar blood vessel weakness and breakage occurs in the eyes of some affected individuals. </s>


Input: Is COL4A1-related brain small-vessel disease inherited ?

Output: 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 most cases, an affected person has one parent with the condition. Rarely, new mutations in the gene occur in people with no history of the disorder in their family. </s>


Input: What are the treatments for COL4A1-related brain small-vessel disease ?

Output: These resources address the diagnosis or management of COL4A1-related brain small-vessel disease:  - Gene Review: Gene Review: COL4A1-Related Disorders  - Genetic Testing Registry: Brain small vessel disease with hemorrhage   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 </s>


Input: What is (are) Canavan disease ?

Output: Canavan disease is a rare inherited disorder that damages the ability of nerve cells (neurons) in the brain to send and receive messages. This disease is one of a group of genetic disorders called leukodystrophies. Leukodystrophies disrupt the growth or maintenance of the myelin sheath, which is the covering that protects nerves and promotes the efficient transmission of nerve impulses.  Neonatal/infantile Canavan disease is the most common and most severe form of the condition. Affected infants appear normal for the first few months of life, but by age 3 to 5 months, problems with development become noticeable. These infants usually do not develop motor skills such as turning over, controlling head movement, and sitting without support. Other common features of this condition include weak muscle tone (hypotonia), an unusually large head size (macrocephaly), and irritability. Feeding and swallowing difficulties, seizures, and sleep disturbances may also develop.  The mild/juvenile form of Canavan disease is less common. Affected individuals have mildly delayed development of speech and motor skills starting in childhood. These delays may be so mild and nonspecific that they are never recognized as being caused by Canavan disease.  The life expectancy for people with Canavan disease varies. Most people with the neonatal/infantile form live only into childhood, although some survive into adolescence or beyond. People with the mild/juvenile form do not appear to have a shortened lifespan. </s>


Input: How many people are affected by Canavan disease ?

Output: While this condition occurs in people of all ethnic backgrounds, it is most common in people of Ashkenazi (eastern and central European) Jewish heritage. Studies suggest that this disorder affects 1 in 6,400 to 13,500 people in the Ashkenazi Jewish population. The incidence in other populations is unknown. </s>


Input: What are the genetic changes related to Canavan disease ?

Output: Mutations in the ASPA gene cause Canavan disease. The ASPA gene provides instructions for making an enzyme called aspartoacylase. This enzyme normally breaks down a compound called N-acetyl-L-aspartic acid (NAA), which is predominantly found in neurons in the brain. The function of NAA is unclear. Researchers had suspected that it played a role in the production of the myelin sheath, but recent studies suggest that NAA does not have this function. The enzyme may instead be involved in the transport of water molecules out of neurons.  Mutations in the ASPA gene reduce the function of aspartoacylase, which prevents the normal breakdown of NAA. The mutations that cause the neonatal/infantile form of Canavan disease severely impair the enzyme's activity, allowing NAA to build up to high levels in the brain. The mutations that cause the mild/juvenile form of the disorder have milder effects on the enzyme's activity, leading to less accumulation of NAA.  An excess of NAA in the brain is associated with the signs and symptoms of Canavan disease. Studies suggest that if NAA is not broken down properly, the resulting chemical imbalance interferes with the formation of the myelin sheath as the nervous system develops. A buildup of NAA also leads to the progressive destruction of existing myelin sheaths. Nerves without this protective covering malfunction, which disrupts normal brain development. </s>


Input: Is Canavan disease inherited ?

Output: 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. </s>


Input: What are the treatments for Canavan disease ?

Output: These resources address the diagnosis or management of Canavan disease:  - Gene Review: Gene Review: Canavan Disease  - Genetic Testing Registry: Canavan disease, mild  - Genetic Testing Registry: Spongy degeneration of central nervous system  - MedlinePlus Encyclopedia: Canavan Disease   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 </s>


Input: What is (are) Brugada syndrome ?

Output: Brugada syndrome is a condition that causes a disruption of the heart's normal rhythm. Specifically, this disorder can lead to irregular heartbeats in the heart's lower chambers (ventricles), which is an abnormality called ventricular arrhythmia. If untreated, the irregular heartbeats can cause fainting (syncope), seizures, difficulty breathing, or sudden death. These complications typically occur when an affected person is resting or asleep.  Brugada syndrome usually becomes apparent in adulthood, although it can develop any time throughout life. Signs and symptoms related to arrhythmias, including sudden death, can occur from early infancy to late adulthood. Sudden death typically occurs around age 40. This condition may explain some cases of sudden infant death syndrome (SIDS), which is a major cause of death in babies younger than 1 year. SIDS is characterized by sudden and unexplained death, usually during sleep.  Sudden unexplained nocturnal death syndrome (SUNDS) is a condition characterized by unexpected cardiac arrest in young adults, usually at night during sleep. This condition was originally described in Southeast Asian populations, where it is a major cause of death. Researchers have determined that SUNDS and Brugada syndrome are the same disorder. </s>


Input: How many people are affected by Brugada syndrome ?

Output: The exact prevalence of Brugada syndrome is unknown, although it is estimated to affect 5 in 10,000 people worldwide. This condition occurs much more frequently in people of Asian ancestry, particularly in Japanese and Southeast Asian populations.  Although Brugada syndrome affects both men and women, the condition appears to be 8 to 10 times more common in men. Researchers suspect that testosterone, a sex hormone present at much higher levels in men, may account for this difference. </s>


Input: What are the genetic changes related to Brugada syndrome ?

Output: Brugada syndrome can be caused by mutations in one of several genes. The most commonly mutated gene in this condition is SCN5A, which is altered in approximately 30 percent of affected individuals. This gene provides instructions for making a sodium channel, which normally transports positively charged sodium atoms (ions) into heart muscle cells. This type of ion channel plays a critical role in maintaining the heart's normal rhythm. Mutations in the SCN5A gene alter the structure or function of the channel, which reduces the flow of sodium ions into cells. A disruption in ion transport alters the way the heart beats, leading to the abnormal heart rhythm characteristic of Brugada syndrome.  Mutations in other genes can also cause Brugada syndrome. Together, these other genetic changes account for less than two percent of cases of the condition. Some of the additional genes involved in Brugada syndrome provide instructions for making proteins that ensure the correct location or function of sodium channels in heart muscle cells. Proteins produced by other genes involved in the condition form or help regulate ion channels that transport calcium or potassium into or out of heart muscle cells. As with sodium channels, proper flow of ions through calcium and potassium channels in the heart muscle helps maintain a regular heartbeat. Mutations in these genes disrupt the flow of ions, impairing the heart's normal rhythm.  In affected people without an identified gene mutation, the cause of Brugada syndrome is often unknown. In some cases, certain drugs may cause a nongenetic (acquired) form of the disorder. Drugs that can induce an altered heart rhythm include medications used to treat some forms of arrhythmia, a condition called angina (which causes chest pain), high blood pressure, depression, and other mental illnesses. Abnormally high blood levels of calcium (hypercalcemia) or potassium (hyperkalemia), as well as unusually low potassium levels (hypokalemia), also have been associated with acquired Brugada syndrome. In addition to causing a nongenetic form of this disorder, these factors may trigger symptoms in people with an underlying mutation in SCN5A or another gene. </s>


Input: Is Brugada syndrome inherited ?

Output: 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 most cases, an affected person has one parent with the condition. Other cases may result from new mutations in the gene. These cases occur in people with no history of the disorder in their family. </s>


Input: What are the treatments for Brugada syndrome ?

Output: These resources address the diagnosis or management of Brugada syndrome:  - Gene Review: Gene Review: Brugada Syndrome  - Genetic Testing Registry: Brugada syndrome  - Genetic Testing Registry: Brugada syndrome 1  - 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 </s>


Input: What is (are) Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant ?

Output: The Say-Barber-Biesecker-Young-Simpson (SBBYS) variant of Ohdo syndrome is a rare condition characterized by genital abnormalities in males, missing or underdeveloped kneecaps (patellae), intellectual disability, distinctive facial features, and abnormalities affecting other parts of the body.  Males with the SBBYS variant of Ohdo syndrome typically have undescended testes (cryptorchidism). Females with this condition have normal genitalia.  Missing or underdeveloped patellae is the most common skeletal abnormality associated with the SBBYS variant of Ohdo syndrome. Affected individuals also have joint stiffness involving the hips, knees, and ankles that can impair movement. Although joints in the lower body are stiff, joints in the arms and upper body may be unusually loose (lax). Many people with this condition have long thumbs and first (big) toes.  The SBBYS variant of Ohdo syndrome is also associated with delayed development and intellectual disability, which are often severe. Many affected infants have weak muscle tone (hypotonia) that leads to breathing and feeding difficulties.  The SBBYS variant of Ohdo syndrome is characterized by a mask-like, non-expressive face. Additionally, affected individuals may have distinctive facial features such as prominent cheeks, a broad nasal bridge or a nose with a rounded tip, a narrowing of the eye opening (blepharophimosis), droopy eyelids (ptosis), and abnormalities of the tear (lacrimal) glands. About one-third of affected individuals are born with an opening in the roof of the mouth called a cleft palate. The SBBYS variant of Ohdo syndrome can also be associated with heart defects and dental problems. </s>


Input: How many people are affected by Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant ?

Output: The SBBYS variant of Ohdo syndrome is estimated to occur in fewer than 1 per million people. At least 19 cases have been reported in the medical literature. </s>


Input: What are the genetic changes related to Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant ?

Output: The SBBYS variant of Ohdo syndrome is caused by mutations in the KAT6B gene. This gene provides instructions for making a type of enzyme called a histone acetyltransferase. These enzymes modify histones, which are structural proteins that attach (bind) to DNA and give chromosomes their shape. By adding a small molecule called an acetyl group to histones, histone acetyltransferases control the activity of certain genes. Little is known about the function of the histone acetyltransferase produced from the KAT6B gene. It appears to regulate genes that are important for early development, including development of the skeleton and nervous system.  The mutations that cause the SBBYS variant of Ohdo syndrome likely prevent the production of functional histone acetyltransferase from one copy of the KAT6B gene in each cell. Studies suggest that the resulting shortage of this enzyme impairs the regulation of various genes during early development. However, it is unclear how these changes lead to the specific features of the condition. </s>


Input: Is Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant inherited ?

Output: This condition has an autosomal dominant inheritance pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. Almost all reported cases have resulted from new mutations in the gene and have occurred in people with no history of the disorder in their family. </s>


Input: What are the treatments for Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant ?

Output: These resources address the diagnosis or management of Ohdo syndrome, SBBYS variant:  - Gene Review: Gene Review: KAT6B-Related Disorders  - Genetic Testing Registry: Young Simpson 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 </s>


Input: What is (are) X-linked juvenile retinoschisis ?

Output: X-linked juvenile retinoschisis is a condition characterized by impaired vision that begins in childhood and occurs almost exclusively in males. This disorder affects the retina, which is a specialized light-sensitive tissue that lines the back of the eye. Damage to the retina impairs the sharpness of vision (visual acuity) in both eyes. Typically, X-linked juvenile retinoschisis affects cells in the central area of the retina called the macula. The macula is responsible for sharp central vision, which is needed for detailed tasks such as reading, driving, and recognizing faces. X-linked juvenile retinoschisis is one type of a broader disorder called macular degeneration, which disrupts the normal functioning of the macula. Occasionally, side (peripheral) vision is affected in people with X-linked juvenile retinoschisis.  X-linked juvenile retinoschisis is usually diagnosed when affected boys start school and poor vision and difficulty with reading become apparent. In more severe cases, eye squinting and involuntary movement of the eyes (nystagmus) begin in infancy. Other early features of X-linked juvenile retinoschisis include eyes that do not look in the same direction (strabismus) and farsightedness (hyperopia). Visual acuity often declines in childhood and adolescence but then stabilizes throughout adulthood until a significant decline in visual acuity typically occurs in a man's fifties or sixties. Sometimes, severe complications develop, such as separation of the retinal layers (retinal detachment) or leakage of blood vessels in the retina (vitreous hemorrhage). These eye abnormalities can further impair vision or cause blindness. </s>


Input: How many people are affected by X-linked juvenile retinoschisis ?

Output: The prevalence of X-linked juvenile retinoschisis is estimated to be 1 in 5,000 to 25,000 men worldwide. </s>


Input: What are the genetic changes related to X-linked juvenile retinoschisis ?

Output: Mutations in the RS1 gene cause most cases of X-linked juvenile retinoschisis. The RS1 gene provides instructions for making a protein called retinoschisin, which is found in the retina. Studies suggest that retinoschisin plays a role in the development and maintenance of the retina. The protein is probably involved in the organization of cells in the retina by attaching cells together (cell adhesion).  RS1 gene mutations result in a decrease in or complete loss of functional retinoschisin, which disrupts the maintenance and organization of cells in the retina. As a result, tiny splits (schisis) or tears form in the retina. This damage often forms a "spoke-wheel" pattern in the macula, which can be seen during an eye examination. In half of affected individuals, these abnormalities can occur in the area of the macula, affecting visual acuity, in the other half of cases the schisis occurs in the sides of the retina, resulting in impaired peripheral vision.  Some individuals with X-linked juvenile retinoschisis do not have a mutation in the RS1 gene. In these individuals, the cause of the disorder is unknown. </s>


Input: Is X-linked juvenile retinoschisis inherited ?

Output: 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. </s>


Input: What are the treatments for X-linked juvenile retinoschisis ?

Output: These resources address the diagnosis or management of X-linked juvenile retinoschisis:  - Gene Review: Gene Review: X-Linked Juvenile Retinoschisis  - Genetic Testing Registry: Juvenile retinoschisis   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 </s>


Input: What is (are) bradyopsia ?

Output: Bradyopsia is a rare condition that affects vision. The term "bradyopsia" is from the Greek words for slow vision. In affected individuals, the eyes adapt more slowly than usual to changing light conditions. For example, people with this condition are blinded for several seconds when going from a dark environment into a bright one, such as when walking out of a darkened movie theater into daylight. Their eyes also have trouble adapting from bright light to dark conditions, such as when driving into a dark tunnel on a sunny day.  Some people with bradyopsia also have difficulty seeing some moving objects, particularly small objects moving against a bright background. As a result, they often have trouble watching or participating in sports with a ball, such as soccer or tennis. People with bradyopsia can have reduced sharpness (acuity) of vision, although acuity may depend on the conditions under which vision is tested. Visual acuity may appear to be severely affected if it is tested under bright lights, but it can be near normal if tested in a dim environment. The ability to see colors and distinguish between them is normal.  The vision problems associated with bradyopsia become apparent in early childhood. They are usually stable, which means they do not worsen over time. </s>


Input: How many people are affected by bradyopsia ?

Output: Bradyopsia appears to be rare. Only a few affected individuals worldwide have been described in the medical literature. </s>


Input: What are the genetic changes related to bradyopsia ?

Output: Bradyopsia can be caused by mutations in the RGS9 gene or in the RGS9BP gene (which is also known as R9AP). These genes provide instructions for making proteins that are necessary for normal vision. The proteins are found in light-detecting cells in the eye called photoreceptors. When light enters the eye, it stimulates specialized pigments in these cells. This stimulation triggers a series of chemical reactions that produce an electrical signal, which is interpreted by the brain as vision. Once photoreceptors have been stimulated by light, they must return to their resting state before they can be stimulated again. The RGS9 and RGS9BP proteins play an essential role in returning photoreceptors to their resting state quickly after light exposure.  Mutations in either the RGS9 or RGS9BP gene prevent photoreceptors from recovering quickly after responding to light. Normally they return to their resting state in a fraction of a second, but in people with mutations in one of these genes, it can take ten seconds or longer. During that time, the photoreceptors cannot respond to light. This delay causes temporary blindness in response to changing light conditions and interferes with seeing small objects when they are in motion.  In some people with bradyopsia, no mutations in the RGS9 or RGS9BP gene have been found. The cause of the condition in these individuals is unknown. </s>


Input: Is bradyopsia inherited ?

Output: 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. </s>


Input: What are the treatments for bradyopsia ?

Output: These resources address the diagnosis or management of bradyopsia:  - Children's Hospital of Pittsburgh: Electroretinogram  - Genetic Testing Registry: Prolonged electroretinal response suppression  - MedlinePlus Encyclopedia: Electroretinography  - Prevent Blindness: Living Well with Low Vision   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 </s>


Input: What is (are) Stargardt macular degeneration ?

Output: Stargardt macular degeneration is a genetic eye disorder that causes progressive vision loss. This disorder affects the retina, the specialized light-sensitive tissue that lines the back of the eye. Specifically, Stargardt macular degeneration affects a small area near the center of the retina called the macula. The macula is responsible for sharp central vision, which is needed for detailed tasks such as reading, driving, and recognizing faces. In most people with Stargardt macular degeneration, a fatty yellow pigment (lipofuscin) builds up in cells underlying the macula. Over time, the abnormal accumulation of this substance can damage cells that are critical for clear central vision. In addition to central vision loss, people with Stargardt macular degeneration have problems with night vision that can make it difficult to navigate in low light. Some affected individuals also have impaired color vision. The signs and symptoms of Stargardt macular degeneration typically appear in late childhood to early adulthood and worsen over time. </s>


Input: How many people are affected by Stargardt macular degeneration ?

Output: Stargardt macular degeneration is the most common form of juvenile macular degeneration, the signs and symptoms of which begin in childhood. The estimated prevalence of Stargardt macular degeneration is 1 in 8,000 to 10,000 individuals. </s>


Input: What are the genetic changes related to Stargardt macular degeneration ?

Output: In most cases, Stargardt macular degeneration is caused by mutations in the ABCA4 gene. Less often, mutations in the ELOVL4 gene cause this condition. The ABCA4 and ELOVL4 genes provide instructions for making proteins that are found in light-sensing (photoreceptor) cells in the retina.  The ABCA4 protein transports potentially toxic substances out of photoreceptor cells. These substances form after phototransduction, the process by which light entering the eye is converted into electrical signals that are transmitted to the brain. Mutations in the ABCA4 gene prevent the ABCA4 protein from removing toxic byproducts from photoreceptor cells. These toxic substances build up and form lipofuscin in the photoreceptor cells and the surrounding cells of the retina, eventually causing cell death. Loss of cells in the retina causes the progressive vision loss characteristic of Stargardt macular degeneration.  The ELOVL4 protein plays a role in making a group of fats called very long-chain fatty acids. The ELOVL4 protein is primarily active (expressed) in the retina, but is also expressed in the brain and skin. The function of very long-chain fatty acids within the retina is unknown. Mutations in the ELOVL4 gene lead to the formation of ELOVL4 protein clumps (aggregates) that build up and may interfere with retinal cell functions, ultimately leading to cell death. </s>


Input: Is Stargardt macular degeneration inherited ?

Output: Stargardt macular degeneration can have different inheritance patterns.  When mutations in the ABCA4 gene cause this condition, it 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.  When this condition is caused by mutations in the ELOVL4 gene, it is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. </s>


Input: What are the treatments for Stargardt macular degeneration ?

Output: These resources address the diagnosis or management of Stargardt macular degeneration:  - Genetic Testing Registry: Stargardt Disease 3  - Genetic Testing Registry: Stargardt disease 1  - Genetic Testing Registry: Stargardt disease 4   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 </s>


Input: What is (are) essential pentosuria ?

Output: Essential pentosuria is a condition characterized by high levels of a sugar called L-xylulose in urine. The condition is so named because L-xylulose is a type of sugar called a pentose. Despite the excess sugar, affected individuals have no associated health problems. </s>


Input: How many people are affected by essential pentosuria ?

Output: Essential pentosuria occurs almost exclusively in individuals with Ashkenazi Jewish ancestry. Approximately 1 in 3,300 people in this population are affected. </s>