bowang0911/MedQuAD huggingface dataset:
These resources address the diagnosis or management of congenital bilateral absence of the vas deferens:  - Gene Review: Gene Review: CFTR-Related Disorders  - Genetic Testing Registry: Congenital bilateral absence of the vas deferens  - MedlinePlus Encyclopedia: Infertility  - MedlinePlus Encyclopedia: Pathway of sperm (image)  - MedlinePlus Health Topic: Assisted Reproductive Technology   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
Mitochondrial trifunctional protein 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 mitochondrial trifunctional protein deficiency may begin during infancy or later in life. Features that occur during infancy include feeding difficulties, lack of energy (lethargy), low blood sugar (hypoglycemia), weak muscle tone (hypotonia), and liver problems. Infants with this disorder are also at high risk for serious heart problems, breathing difficulties, coma, and sudden death. Signs and symptoms of mitochondrial trifunctional protein deficiency that may begin after infancy include hypotonia, muscle pain, a breakdown of muscle tissue, and a loss of sensation in the extremities (peripheral neuropathy).  Problems related to mitochondrial trifunctional protein 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 and HADHB genes cause mitochondrial trifunctional protein deficiency. These genes each provide 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 or HADHB genes that cause mitochondrial trifunctional protein deficiency disrupt all three functions of this enzyme complex. Without enough of this enzyme complex, long-chain fatty acids from food and body fat cannot be metabolized and processed. 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, and muscles. This abnormal buildup causes the other signs and symptoms of mitochondrial trifunctional protein deficiency.
These resources address the diagnosis or management of mitochondrial trifunctional protein deficiency:  - Baby's First Test  - Genetic Testing Registry: Mitochondrial trifunctional protein 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
Glycogen storage disease type I (also known as GSDI or von Gierke disease) is an inherited disorder caused by the buildup of a complex sugar called glycogen in the body's cells. The accumulation of glycogen in certain organs and tissues, especially the liver, kidneys, and small intestines, impairs their ability to function normally.  Signs and symptoms of this condition typically appear around the age of 3 or 4 months, when babies start to sleep through the night and do not eat as frequently as newborns. Affected infants may have low blood sugar (hypoglycemia), which can lead to seizures. They can also have a buildup of lactic acid in the body (lactic acidosis), high blood levels of a waste product called uric acid (hyperuricemia), and excess amounts of fats in the blood (hyperlipidemia). As they get older, children with GSDI have thin arms and legs and short stature. An enlarged liver may give the appearance of a protruding abdomen. The kidneys may also be enlarged. Affected individuals may also have diarrhea and deposits of cholesterol in the skin (xanthomas).  People with GSDI may experience delayed puberty. Beginning in young to mid-adulthood, affected individuals may have thinning of the bones (osteoporosis), a form of arthritis resulting from uric acid crystals in the joints (gout), kidney disease, and high blood pressure in the blood vessels that supply the lungs (pulmonary hypertension). Females with this condition may also have abnormal development of the ovaries (polycystic ovaries). In affected teens and adults, tumors called adenomas may form in the liver. Adenomas are usually noncancerous (benign), but occasionally these tumors can become cancerous (malignant).  Researchers have described two types of GSDI, which differ in their signs and symptoms and genetic cause. These types are known as glycogen storage disease type Ia (GSDIa) and glycogen storage disease type Ib (GSDIb). Two other forms of GSDI have been described, and they were originally named types Ic and Id. However, these types are now known to be variations of GSDIb; for this reason, GSDIb is sometimes called GSD type I non-a.  Many people with GSDIb have a shortage of white blood cells (neutropenia), which can make them prone to recurrent bacterial infections. Neutropenia is usually apparent by age 1. Many affected individuals also have inflammation of the intestinal walls (inflammatory bowel disease). People with GSDIb may have oral problems including cavities, inflammation of the gums (gingivitis), chronic gum (periodontal) disease, abnormal tooth development, and open sores (ulcers) in the mouth. The neutropenia and oral problems are specific to people with GSDIb and are typically not seen in people with GSDIa.
Mutations in two genes, G6PC and SLC37A4, cause GSDI. G6PC gene mutations cause GSDIa, and SLC37A4 gene mutations cause GSDIb.  The proteins produced from the G6PC and SLC37A4 genes work together to break down a type of sugar molecule called glucose 6-phosphate. The breakdown of this molecule produces the simple sugar glucose, which is the primary energy source for most cells in the body.  Mutations in the G6PC and SLC37A4 genes prevent the effective breakdown of glucose 6-phosphate. Glucose 6-phosphate that is not broken down to glucose is converted to glycogen and fat so it can be stored within cells. Too much glycogen and fat stored within a cell can be toxic. This buildup damages organs and tissues throughout the body, particularly the liver and kidneys, leading to the signs and symptoms of GSDI.
These resources address the diagnosis or management of glycogen storage disease type I:  - American Liver Foundation  - Canadian Liver Foundation  - Gene Review: Gene Review: Glycogen Storage Disease Type I  - Genetic Testing Registry: Glucose-6-phosphate transport defect  - Genetic Testing Registry: Glycogen storage disease type 1A  - Genetic Testing Registry: Glycogen storage disease, type I  - MedlinePlus Encyclopedia: Von Gierke 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
Short-chain acyl-CoA dehydrogenase (SCAD) deficiency is a condition that prevents the body from converting certain fats into energy, especially during periods without food (fasting).  Signs and symptoms of SCAD deficiency may appear during infancy or early childhood and can include vomiting, low blood sugar (hypoglycemia), a lack of energy (lethargy), poor feeding, and failure to gain weight and grow at the expected rate (failure to thrive). Other features of this disorder may include poor muscle tone (hypotonia), seizures, developmental delay, and a small head size (microcephaly).  The symptoms of SCAD deficiency may be triggered by fasting or illnesses such as viral infections. This disorder is sometimes mistaken for Reye syndrome, a severe condition 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.  In some people with SCAD deficiency, signs and symptoms do not appear until adulthood. These individuals are more likely to have problems related to muscle weakness and wasting.  The severity of this condition varies widely, even among members of the same family. Some individuals are diagnosed with SCAD deficiency based on laboratory testing but never develop any symptoms of the condition.
Mutations in the ACADS gene cause SCAD deficiency. This gene provides instructions for making an enzyme called short-chain acyl-CoA dehydrogenase, which is required to break down (metabolize) a group of fats called short-chain fatty acids. 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 ACADS gene lead to a shortage (deficiency) of the SCAD enzyme within cells. Without sufficient amounts of this enzyme, short-chain fatty acids are not metabolized properly. As a result, these fats are not converted into energy, which can lead to the signs and symptoms of this disorder, such as lethargy, hypoglycemia, and muscle weakness. It remains unclear why some people with SCAD deficiency never develop any symptoms.
These resources address the diagnosis or management of SCAD deficiency:  - Baby's First Test  - Gene Review: Gene Review: Short-Chain Acyl-CoA Dehydrogenase Deficiency  - Genetic Testing Registry: Deficiency of butyryl-CoA dehydrogenase  - MedlinePlus Encyclopedia: Newborn Screening Tests   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
Refsum disease is an inherited condition that causes vision loss, absence of the sense of smell (anosmia), and a variety of other signs and symptoms.  The vision loss associated with Refsum disease is caused by an eye disorder called retinitis pigmentosa. This disorder affects the retina, the light-sensitive layer at the back of the eye. Vision loss occurs as the light-sensing cells of the retina gradually deteriorate. The first sign of retinitis pigmentosa is usually a loss of night vision, which often becomes apparent in childhood. Over a period of years, the disease disrupts side (peripheral) vision and may eventually lead to blindness.  Vision loss and anosmia are seen in almost everyone with Refsum disease, but other signs and symptoms vary. About one-third of affected individuals are born with bone abnormalities of the hands and feet. Features that appear later in life can include progressive muscle weakness and wasting; poor balance and coordination (ataxia); hearing loss; and dry, scaly skin (ichthyosis). Additionally, some people with Refsum disease develop an abnormal heart rhythm (arrhythmia) and related heart problems that can be life-threatening.
More than 90 percent of all cases of Refsum disease result from mutations in the PHYH gene. The remaining cases are caused by mutations in a gene called PEX7.  The signs and symptoms of Refsum disease result from the abnormal buildup of a type of fatty acid called phytanic acid. This substance is obtained from the diet, particularly from beef and dairy products. It is normally broken down through a process called alpha-oxidation, which occurs in cell structures called peroxisomes. These sac-like compartments contain enzymes that process many different substances, such as fatty acids and certain toxic compounds.  Mutations in either the PHYH or PEX7 gene disrupt the usual functions of peroxisomes, including the breakdown of phytanic acid. As a result, this substance builds up in the body's tissues. The accumulation of phytanic acid is toxic to cells, although it is unclear how an excess of this substance affects vision and smell and causes the other specific features of Refsum disease.
These resources address the diagnosis or management of Refsum disease:  - Gene Review: Gene Review: Refsum Disease  - Gene Review: Gene Review: Retinitis Pigmentosa Overview  - Genetic Testing Registry: Phytanic acid storage disease  - MedlinePlus Encyclopedia: Retinitis Pigmentosa   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
DMD-associated dilated cardiomyopathy is a form of heart disease that is caused by mutations in the DMD gene. Dilated cardiomyopathy enlarges and weakens the heart (cardiac) muscle, preventing the heart from pumping blood efficiently. Signs and symptoms of this condition can include an irregular heartbeat (arrhythmia), shortness of breath, extreme tiredness (fatigue), and swelling of the legs and feet. In males with DMD-associated dilated cardiomyopathy, heart problems usually develop early in life and worsen quickly, leading to heart failure in adolescence or early adulthood. In affected females, the condition appears later in life and worsens more slowly.  Dilated cardiomyopathy is a feature of two related conditions that are also caused by mutations in the DMD gene: Duchenne and Becker muscular dystrophy. In addition to heart disease, these conditions are characterized by progressive weakness and wasting of muscles used for movement (skeletal muscles). People with DMD-associated dilated cardiomyopathy typically do not have any skeletal muscle weakness or wasting, although they may have subtle changes in their skeletal muscle cells that are detectable through laboratory testing. Based on these skeletal muscle changes, DMD-associated dilated cardiomyopathy is sometimes classified as subclinical Becker muscular dystrophy.
DMD-associated dilated cardiomyopathy results from mutations in the DMD gene. This gene provides instructions for making a protein called dystrophin, which helps stabilize and protect muscle fibers and may play a role in chemical signaling within cells. The mutations responsible for DMD-associated dilated cardiomyopathy preferentially affect the activity of dystrophin in cardiac muscle cells. As a result of these mutations, affected individuals typically have little or no functional dystrophin in the heart. Without enough of this protein, cardiac muscle cells become damaged as the heart muscle repeatedly contracts and relaxes. The damaged muscle cells weaken and die over time, leading to the heart problems characteristic of DMD-associated dilated cardiomyopathy.  The mutations that cause DMD-associated dilated cardiomyopathy often lead to reduced amounts of dystrophin in skeletal muscle cells. However, enough of this protein is present to prevent weakness and wasting of the skeletal muscles.  Because DMD-associated dilated cardiomyopathy results from a shortage of dystrophin, it is classified as a dystrophinopathy.
DMD-associated dilated cardiomyopathy has an X-linked pattern of inheritance. The DMD gene is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a mutation in one of the two copies of the gene in each cell usually leads to relatively mild heart disease that appears later in life. In males (who have only one X chromosome), a mutation in the only copy of the gene in each cell causes more severe signs and symptoms that occur earlier in life. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.
These resources address the diagnosis or management of DMD-associated dilated cardiomyopathy:  - Gene Review: Gene Review: Dilated Cardiomyopathy Overview  - Gene Review: Gene Review: Dystrophinopathies  - Genetic Testing Registry: Dilated cardiomyopathy 3B  - Genetic Testing Registry: Duchenne muscular dystrophy  - National Heart, Lung, and Blood Institute: How Is Cardiomyopathy Diagnosed?  - National Heart, Lung, and Blood Institute: How Is Cardiomyopathy Treated?   These resources from MedlinePlus offer information about the diagnosis and management of various health conditions:  - Diagnostic Tests  - Drug Therapy  - Surgery and Rehabilitation  - Genetic Counseling   - Palliative Care
Sporadic hemiplegic migraine is a rare form of migraine headache. Migraines typically cause intense, throbbing pain in one area of the head. Some people with migraines also experience nausea, vomiting, and sensitivity to light and sound. These recurrent headaches typically begin in childhood or adolescence and can be triggered by certain foods, emotional stress, and minor head trauma. Each headache may last from a few hours to a few days.  In sporadic hemiplegic migraine and some other types of migraine, a pattern of neurological symptoms called an aura occurs before onset of the headache. An aura commonly includes temporary visual changes such as blind spots (scotomas), flashing lights, zig-zagging lines, and double vision. In people with sporadic hemiplegic migraine, auras are also characterized by temporary numbness or weakness, often affecting one side of the body (hemiparesis). Additional features of an aura can include difficulty with speech, confusion, and drowsiness. An aura typically develops gradually over a few minutes and lasts about an hour.  Some people with sporadic hemiplegic migraine experience unusually severe migraine episodes. These episodes can include fever, prolonged weakness, seizures, and coma. Although most people with sporadic hemiplegic migraine recover completely between episodes, neurological symptoms such as memory loss and problems with attention can last for weeks or months. Some affected individuals develop mild but permanent difficulty coordinating movements (ataxia), which may worsen with time, and rapid, involuntary eye movements called nystagmus. Mild to severe intellectual disability has been reported in some people with sporadic hemiplegic migraine.
Mutations in the ATP1A2 and CACNA1A genes have been found to cause sporadic hemiplegic migraine. The proteins produced from these genes transport charged atoms (ions) across cell membranes. The movement of these ions is critical for normal signaling between nerve cells (neurons) in the brain and other parts of the nervous system. Signaling between neurons relies on chemicals called neurotransmitters, which are released from one neuron and taken up by neighboring neurons. Mutations in the ATP1A2 and CACNA1A genes disrupt the transport of ions in neurons, which is thought to impair the normal release and uptake of certain neurotransmitters in the brain. The resulting abnormal signaling may lead to the severe headaches and auras characteristic of sporadic hemiplegic migraine.  Many people with sporadic hemiplegic migraine do not have a mutation in one of the known genes. Researchers believe that mutations in other genes are also involved in the condition, although these genes have not been identified.  There is little evidence that mutations in the CACNA1A and ATP1A2 genes play a role in common migraines, which affect millions of people each year. Researchers are searching for additional genetic changes that may underlie rare types of migraine, such as sporadic hemiplegic migraine, as well as the more common forms of migraine.
Sporadic means that the condition occurs in individuals with no history of the disorder in their family. While most cases result from new (de novo) mutations that likely occur during early embryonic development, some affected individuals inherit the genetic change that causes the condition from an unaffected parent. (When some people with the mutation have no signs and symptoms of the disorder, the condition is said to have reduced penetrance.) Although family members of an affected individual do not have sporadic hemiplegic migraine, some experience migraine headaches without hemiparesis. A related condition, familial hemiplegic migraine, has signs and symptoms identical to those in sporadic hemiplegic migraine but occurs in multiple members of a family.
These resources address the diagnosis or management of sporadic hemiplegic migraine:  - Genetic Testing Registry: Migraine, sporadic hemiplegic  - Journal of the American Medical Association Patient Page: Migraine Headache   These resources from MedlinePlus offer information about the diagnosis and management of various health conditions:  - Diagnostic Tests  - Drug Therapy  - Surgery and Rehabilitation  - Genetic Counseling   - Palliative Care
Isolated Duane retraction syndrome is a disorder of eye movement. This condition prevents outward movement of the eye (toward the ear), and in some cases may also limit inward eye movement (toward the nose). As the eye moves inward, the eyelids partially close and the eyeball pulls back (retracts) into its socket. Most commonly, only one eye is affected. About 10 percent of people with isolated Duane retraction syndrome develop amblyopia ("lazy eye"), a condition that causes vision loss in the affected eye.  About 70 percent of all cases of Duane retraction syndrome are isolated, which means they occur without other signs and symptoms. Duane retraction syndrome can also occur as part of syndromes that affect other areas of the body. For example, Duane-radial ray syndrome is characterized by this eye disorder in conjunction with abnormalities of bones in the arms and hands.  Researchers have identified three forms of isolated Duane retraction syndrome, designated types I, II, and III. The types vary in which eye movements are most severely restricted (inward, outward, or both). All three types are characterized by retraction of the eyeball as the eye moves inward.
In most people with isolated Duane retraction syndrome, the cause of the condition is unknown. However, researchers have identified mutations in one gene, CHN1, that cause the disorder in a small number of families. The CHN1 gene provides instructions for making a protein that is involved in the early development of the nervous system. Specifically, the protein appears to be critical for the formation of nerves that control several of the muscles surrounding the eyes (extraocular muscles). Mutations in the CHN1 gene disrupt the normal development of these nerves and the extraocular muscles needed for side-to-side eye movement. Abnormal function of these muscles leads to restricted eye movement and related problems with vision.