bowang0911/MedQuAD huggingface dataset:
Campomelic dysplasia is a severe disorder that affects development of the skeleton, reproductive system, and other parts of the body. This condition is often life-threatening in the newborn period.  The term "campomelic" comes from the Greek words for "bent limb." Affected individuals are typically born with bowing of the long bones in the legs, and occasionally, bowing in the arms. Bowing can cause characteristic skin dimples to form over the curved bone, especially on the lower legs. People with campomelic dysplasia usually have short legs, dislocated hips, underdeveloped shoulder blades, 11 pairs of ribs instead of 12, bone abnormalities in the neck, and inward- and upward-turning feet (clubfeet). These skeletal abnormalities begin developing before birth and can often be seen on ultrasound. When affected individuals have features of this disorder but do not have bowed limbs, they are said to have acampomelic campomelic dysplasia.  Many people with campomelic dysplasia have external genitalia that do not look clearly male or clearly female (ambiguous genitalia). Approximately 75 percent of affected individuals with a typical male chromosome pattern (46,XY) have ambiguous genitalia or normal female genitalia. Internal reproductive organs may not correspond with the external genitalia; the internal organs can be male (testes), female (ovaries), or a combination of the two. For example, an individual with female external genitalia may have testes or a combination of testes and ovaries.  Affected individuals have distinctive facial features, including a small chin, prominent eyes, and a flat face. They also have a large head compared to their body size. A particular group of physical features, called Pierre Robin sequence, is common in people with campomelic dysplasia. Pierre Robin sequence includes an opening in the roof of the mouth (a cleft palate), a tongue that is placed further back than normal (glossoptosis), and a small lower jaw (micrognathia). People with campomelic dysplasia are often born with weakened cartilage that forms the upper respiratory tract. This abnormality, called laryngotracheomalacia, partially blocks the airway and causes difficulty breathing. Laryngotracheomalacia contributes to the poor survival of infants with campomelic dysplasia.  Only a few people with campomelic dysplasia survive past infancy. As these individuals age, they may develop an abnormal curvature of the spine (scoliosis) and other spine abnormalities that compress the spinal cord. People with campomelic dysplasia may also have short stature and hearing loss.
Mutations in or near the SOX9 gene cause campomelic dysplasia. This gene provides instructions for making a protein that plays a critical role in the formation of many different tissues and organs during embryonic development. The SOX9 protein regulates the activity of other genes, especially those that are important for development of the skeleton and reproductive organs.  Most cases of campomelic dysplasia are caused by mutations within the SOX9 gene. These mutations prevent the production of the SOX9 protein or result in a protein with impaired function. About 5 percent of cases are caused by chromosome abnormalities that occur near the SOX9 gene; these cases tend to be milder than those caused by mutations within the SOX9 gene. The chromosome abnormalities disrupt regions of DNA that normally regulate the activity of the SOX9 gene. All of these genetic changes prevent the SOX9 protein from properly controlling the genes essential for normal development of the skeleton, reproductive system, and other parts of the body. Abnormal development of these structures causes the signs and symptoms of campomelic dysplasia.
These resources address the diagnosis or management of campomelic dysplasia:  - European Skeletal Dysplasia Network  - Gene Review: Gene Review: Campomelic Dysplasia  - Genetic Testing Registry: Camptomelic dysplasia  - MedlinePlus Encyclopedia: Ambiguous Genitalia  - MedlinePlus Encyclopedia: Pierre-Robin Syndrome  - The Hospital for Sick Children   These resources from MedlinePlus offer information about the diagnosis and management of various health conditions:  - Diagnostic Tests  - Drug Therapy  - Surgery and Rehabilitation  - Genetic Counseling   - Palliative Care
Glycogen storage disease type 0 (also known as GSD 0) is a condition caused by the body's inability to form a complex sugar called glycogen, which is a major source of stored energy in the body. GSD 0 has two types: in muscle GSD 0, glycogen formation in the muscles is impaired, and in liver GSD 0, glycogen formation in the liver is impaired.  The signs and symptoms of muscle GSD 0 typically begin in early childhood. Affected individuals often experience muscle pain and weakness or episodes of fainting (syncope) following moderate physical activity, such as walking up stairs. The loss of consciousness that occurs with fainting typically lasts up to several hours. Some individuals with muscle GSD 0 have a disruption of the heart's normal rhythm (arrhythmia) known as long QT syndrome. In all affected individuals, muscle GSD 0 impairs the heart's ability to effectively pump blood and increases the risk of cardiac arrest and sudden death, particularly after physical activity. Sudden death from cardiac arrest can occur in childhood or adolescence in people with muscle GSD 0.  Individuals with liver GSD 0 usually show signs and symptoms of the disorder in infancy. People with this disorder develop low blood sugar (hypoglycemia) after going long periods of time without food (fasting). Signs of hypoglycemia become apparent when affected infants begin sleeping through the night and stop late-night feedings; these infants exhibit extreme tiredness (lethargy), pale skin (pallor), and nausea. During episodes of fasting, ketone levels in the blood may increase (ketosis). Ketones are molecules produced during the breakdown of fats, which occurs when stored sugars (such as glycogen) are unavailable. These short-term signs and symptoms of liver GSD 0 often improve when food is eaten and sugar levels in the body return to normal. The features of liver GSD 0 vary; they can be mild and go unnoticed for years, or they can include developmental delay and growth failure.
Mutations in the GYS1 gene cause muscle GSD 0, and mutations in the GYS2 gene cause liver GSD 0. These genes provide instructions for making different versions of an enzyme called glycogen synthase. Both versions of glycogen synthase have the same function, to form glycogen molecules by linking together molecules of the simple sugar glucose, although they perform this function in different regions of the body.  The GYS1 gene provides instructions for making muscle glycogen synthase; this form of the enzyme is produced in most cells, but it is especially abundant in heart (cardiac) muscle and the muscles used for movement (skeletal muscles). During cardiac muscle contractions or rapid or sustained movement of skeletal muscle, glycogen stored in muscle cells is broken down to supply the cells with energy.  The GYS2 gene provides instructions for making liver glycogen synthase, which is produced solely in liver cells. Glycogen that is stored in the liver can be broken down rapidly when glucose is needed to maintain normal blood sugar levels between meals.  Mutations in the GYS1 or GYS2 gene lead to a lack of functional glycogen synthase, which prevents the production of glycogen from glucose. Mutations that cause GSD 0 result in a complete absence of glycogen in either liver or muscle cells. As a result, these cells do not have glycogen as a source of stored energy to draw upon following physical activity or fasting. This shortage of glycogen leads to the signs and symptoms of GSD 0.
These resources address the diagnosis or management of glycogen storage disease type 0:  - Genetic Testing Registry: Glycogen storage disease 0, muscle  - Genetic Testing Registry: Hypoglycemia with deficiency of glycogen synthetase in the liver   These resources from MedlinePlus offer information about the diagnosis and management of various health conditions:  - Diagnostic Tests  - Drug Therapy  - Surgery and Rehabilitation  - Genetic Counseling   - Palliative Care
Congenital fiber-type disproportion is a condition that primarily affects skeletal muscles, which are muscles used for movement. People with this condition typically experience muscle weakness (myopathy), particularly in the muscles of the shoulders, upper arms, hips, and thighs. Weakness can also affect the muscles of the face and muscles that control eye movement (ophthalmoplegia), sometimes causing droopy eyelids (ptosis). Individuals with congenital fiber-type disproportion generally have a long face, a high arch in the roof of the mouth (high-arched palate), and crowded teeth. Affected individuals may have joint deformities (contractures) and an abnormally curved lower back (lordosis) or a spine that curves to the side (scoliosis). Approximately 30 percent of people with this disorder experience mild to severe breathing problems related to weakness of muscles needed for breathing. Some people who experience these breathing problems require use of a machine to help regulate their breathing at night (noninvasive mechanical ventilation), and occasionally during the day as well. About 30 percent of affected individuals have difficulty swallowing due to muscle weakness in the throat. Rarely, people with this condition have a weakened and enlarged heart muscle (dilated cardiomyopathy).  The severity of congenital fiber-type disproportion varies widely. It is estimated that up to 25 percent of affected individuals experience severe muscle weakness at birth and die in infancy or childhood. Others have only mild muscle weakness that becomes apparent in adulthood. Most often, the signs and symptoms of this condition appear by age 1. The first signs of this condition are usually decreased muscle tone (hypotonia) and muscle weakness. In most cases, muscle weakness does not worsen over time, and in some instances it may improve. Although motor skills such as standing and walking may be delayed, many affected children eventually learn to walk. These individuals often have less stamina than their peers, but they remain active. Rarely, people with this condition have a progressive decline in muscle strength over time. These individuals may lose the ability to walk and require wheelchair assistance.
Mutations in multiple genes can cause congenital fiber-type disproportion. Mutations in the TPM3, RYR1 and ACTA1 genes cause 35 to 50 percent of cases, while mutations in other genes, some known and some unidentified, are responsible for the remaining cases.  The genes that cause congenital fiber-type disproportion provide instructions for making proteins that are involved in the tensing of muscle fibers (muscle contraction). Changes in these proteins lead to impaired muscle contraction, resulting in muscle weakness.  Skeletal muscle is made up of two types of muscle fibers: type I (slow twitch fibers) and type II (fast twitch fibers). Normally, type I and type II fibers are the same size. In people with congenital fiber-type disproportion, type I skeletal muscle fibers are significantly smaller than type II skeletal muscle fibers. It is unclear whether the small type I skeletal muscle fibers lead to muscle weakness or are caused by muscle weakness in people with congenital fiber-type disproportion.
Congenital fiber-type disproportion can have multiple inheritance patterns.  When this condition is caused by mutations in the ACTA1 gene, it usually occurs in an autosomal dominant pattern. Autosomal dominant inheritance means one copy of the altered gene in each cell is sufficient to cause the disorder.  Most other cases of congenital fiber-type disproportion, including those caused by mutations in the RYR1 gene, have 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.  When this condition is caused by mutations in the TPM3 gene, it can occur in either an autosomal dominant or autosomal recessive pattern.  In rare cases, this condition can be inherited in an X-linked pattern, although the gene or genes associated with X-linked congenital fiber-type disproportion have not been identified. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes in each cell. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. Because females have two copies of the X chromosome, one altered copy of the gene in each cell usually leads to less severe symptoms in females than in males or may cause no symptoms at all. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.  It is estimated that 40 percent of individuals with congenital fiber-type disproportion have an affected relative.
These resources address the diagnosis or management of congenital fiber-type disproportion:  - Gene Review: Gene Review: Congenital Fiber-Type Disproportion  - Genetic Testing Registry: Congenital myopathy with fiber type disproportion  - MedlinePlus Encyclopedia: Contracture Deformity  - MedlinePlus Encyclopedia: Hypotonia   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
Type A insulin resistance syndrome is a rare disorder characterized by severe insulin resistance, a condition in which the body's tissues and organs do not respond properly to the hormone insulin. Insulin normally helps regulate blood sugar levels by controlling how much sugar (in the form of glucose) is passed from the bloodstream into cells to be used as energy. In people with type A insulin resistance syndrome, insulin resistance impairs blood sugar regulation and ultimately leads to a condition called diabetes mellitus, in which blood sugar levels can become dangerously high.  Severe insulin resistance also underlies the other signs and symptoms of type A insulin resistance syndrome. In affected females, the major features of the condition become apparent in adolescence. Many affected females do not begin menstruation by age 16 (primary amenorrhea) or their periods may be light and irregular (oligomenorrhea). They develop cysts on the ovaries and excessive body hair growth (hirsutism). Most affected females also develop a skin condition called acanthosis nigricans, in which the skin in body folds and creases becomes thick, dark, and velvety. Unlike most people with insulin resistance, females with type A insulin resistance syndrome are usually not overweight.  The features of type A insulin resistance syndrome are more subtle in affected males. Some males have low blood sugar (hypoglycemia) as the only sign; others may also have acanthosis nigricans. In many cases, males with this condition come to medical attention only when they develop diabetes mellitus in adulthood.  Type A insulin resistance syndrome is one of a group of related conditions described as inherited severe insulin resistance syndromes. These disorders, which also include Donohue syndrome and Rabson-Mendenhall syndrome, are considered part of a spectrum. Type A insulin resistance syndrome represents the mildest end of the spectrum: its features often do not become apparent until puberty or later, and it is generally not life-threatening.
Type A insulin resistance syndrome results from mutations in the INSR gene. This gene provides instructions for making a protein called an insulin receptor, which is found in many types of cells. Insulin receptors are embedded in the outer membrane surrounding the cell, where they attach (bind) to insulin circulating in the bloodstream. This binding triggers signaling pathways that influence many cell functions.  Most of the INSR gene mutations that cause type A insulin resistance syndrome lead to the production of a faulty insulin receptor that cannot transmit signals properly. Although insulin is present in the bloodstream, the defective receptors make it less able to exert its effects on cells and tissues. This severe resistance to the effects of insulin impairs blood sugar regulation and leads to diabetes mellitus. In females with type A insulin resistance syndrome, excess insulin in the bloodstream interacts with hormonal factors during adolescence to cause abnormalities of the menstrual cycle, ovarian cysts, and other features of the disorder.  This condition is designated as type A to distinguish it from type B insulin resistance syndrome. Although the two disorders have similar signs and symptoms, type B is not caused by INSR gene mutations; instead, it results from an abnormality of the immune system that blocks insulin receptor function.
Type A insulin resistance syndrome can have either an autosomal dominant or, less commonly, an autosomal recessive pattern of inheritance.  In autosomal dominant inheritance, 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 autosomal recessive inheritance, 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.
Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency is a rare condition that prevents the body from converting certain fats to energy, particularly during periods without food (fasting).  Signs and symptoms of LCHAD deficiency typically appear during infancy or early childhood and can include feeding difficulties, lack of energy (lethargy), low blood sugar (hypoglycemia), weak muscle tone (hypotonia), liver problems, and abnormalities in the light-sensitive tissue at the back of the eye (retina). Later in childhood, people with this condition may experience muscle pain, breakdown of muscle tissue, and a loss of sensation in their arms and legs (peripheral neuropathy). Individuals with LCHAD deficiency are also at risk for serious heart problems, breathing difficulties, coma, and sudden death.  Problems related to LCHAD 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.
Mutations in the HADHA gene cause LCHAD deficiency. The HADHA gene provides instructions for making part of an enzyme complex called mitochondrial trifunctional protein. This enzyme complex functions in mitochondria, the energy-producing centers within cells. As the name suggests, mitochondrial trifunctional protein contains three enzymes that each perform a different function. This enzyme complex is required to break down (metabolize) a group of fats called long-chain fatty acids. Long-chain fatty acids are found in foods such as milk and certain oils. These fatty acids are stored in the body's fat tissues. 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 HADHA gene that cause LCHAD deficiency disrupt one of the functions of this enzyme complex. These mutations prevent the normal processing of long-chain fatty acids from food and body fat. As a result, these fatty acids are not converted to energy, which can lead to some features of this disorder, such as lethargy and hypoglycemia. Long-chain fatty acids or partially metabolized fatty acids may also build up and damage the liver, heart, muscles, and retina. This abnormal buildup causes the other signs and symptoms of LCHAD deficiency.
These resources address the diagnosis or management of LCHAD deficiency:  - Baby's First Test  - Genetic Testing Registry: Long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency  - MedlinePlus Encyclopedia: Hypoglycemia  - MedlinePlus Encyclopedia: Peripheral Neuropathy   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
Optic atrophy type 1 is a condition that affects vision. Individuals with this condition have progressive vision loss that typically begins within the first decade of life. The severity of the vision loss varies widely among affected people, even among members of the same family. People with this condition can range from having nearly normal vision to complete blindness. The vision loss usually progresses slowly.  People with optic atrophy type 1 frequently have problems with color vision that make it difficult or impossible to distinguish between shades of blue and green. Other vision problems associated with this condition include a progressive narrowing of the field of vision (tunnel vision) and an abnormally pale appearance (pallor) of the nerve that relays visual information from the eye to the brain (optic nerve). Optic nerve pallor can be detected during an eye examination.
Optic atrophy type 1 is caused by mutations in the OPA1 gene. The protein produced from this gene is made in many types of cells and tissues throughout the body. The OPA1 protein is found inside mitochondria, which are the energy-producing centers of cells. The OPA1 protein plays a key role in the organization of the shape and structure of the mitochondria and in the self-destruction of cells (apoptosis). The OPA1 protein is also involved in a process called oxidative phosphorylation, from which cells derive much of their energy. Additionally, the protein plays a role in the maintenance of the small amount of DNA within mitochondria, called mitochondrial DNA (mtDNA).  Mutations in the OPA1 gene lead to overall dysfunction of mitochondria. The structure of the mitochondria become disorganized and cells are more susceptible to self-destruction. OPA1 gene mutations lead to mitochondria with reduced energy-producing capabilities. The maintenance of mtDNA is also sometimes impaired, resulting in mtDNA mutations.  The vision problems experienced by people with optic atrophy type 1 are due to mitochondrial dysfunction, leading to the breakdown of structures that transmit visual information from the eyes to the brain. Affected individuals first experience a progressive loss of nerve cells within the retina, called retinal ganglion cells. The loss of these cells is followed by the degeneration (atrophy) of the optic nerve. The optic nerve is partly made up of specialized extensions of retinal ganglion cells called axons; when the retinal ganglion cells die, the optic nerve cannot transmit visual information to the brain normally.  It is unclear why the OPA1 gene mutations that cause optic atrophy type 1 only affect the eyes. Retinal ganglion cells have many mitochondria and especially high energy requirements, which researchers believe may make them particularly vulnerable to mitochondrial dysfunction and decreases in energy production.  Some individuals with optic atrophy type 1 do not have identified mutations in the OPA1 gene. In these cases, the cause of the condition is unknown.