bowang0911/MedQuAD huggingface dataset:
Renal coloboma syndrome (also known as papillorenal syndrome) is a condition that primarily affects kidney (renal) and eye development. People with this condition typically have kidneys that are small and underdeveloped (hypoplastic), which can lead to end-stage renal disease (ESRD). This serious disease occurs when the kidneys are no longer able to filter fluids and waste products from the body effectively. It has been estimated that approximately ten percent of children with hypoplastic kidneys may have renal coloboma syndrome. The kidney problems can affect one or both kidneys.  Additionally, people with renal coloboma syndrome may have a malformation in the optic nerve, a structure that carries information from the eye to the brain. Optic nerve malformations are sometimes associated with a gap or hole (coloboma) in the light-sensitive tissue at the back of the eye (the retina). The vision problems caused by these abnormalities can vary depending on the size and location of the malformation. Some people have no visual problems, while others may have severely impaired vision.  Less common features of renal coloboma syndrome include backflow of urine from the bladder (vesicoureteral reflux), multiple kidney cysts, loose joints, and mild hearing loss.
Renal coloboma syndrome is caused by mutations in the PAX2 gene. The PAX2 gene provides instructions for making a protein that is involved in the early development of the eyes, ears, brain and spinal cord (central nervous system), kidneys, and genital tract. The PAX2 protein attaches (binds) to specific regions of DNA and regulates the activity of other genes. On the basis of this role, the PAX2 protein is called a transcription factor. After birth, the PAX2 protein is thought to protect against cell death during periods of cellular stress.  Mutations in the PAX2 gene lead to the production of a nonfunctional PAX2 protein that is unable to aid in development, causing incomplete formation of certain tissues. Why the kidneys and eyes are specifically affected by PAX2 gene mutations is unclear.  Approximately half of those affected with renal coloboma syndrome do not have an identified mutation in the PAX2 gene. In these cases, the cause of the disorder is unknown.
Sjgren-Larsson syndrome is a condition characterized by dry, scaly skin (ichthyosis); neurological problems; and eye problems. These symptoms are apparent by early childhood and usually do not worsen with age.  Affected infants tend to be born prematurely. At birth the skin is red (erythema), but later in infancy the skin becomes dry, rough, and scaly with a brownish or yellowish tone. Mild to severe itchiness (pruritus) is also common. These skin abnormalities are generally dispersed over the whole body, most severely affecting the nape of the neck, the torso, and the extremities. The skin of the face is usually not affected.  People with this condition may also have neurological signs and symptoms. Most affected individuals have leukoencephalopathy, which is a change in a type of brain tissue called white matter. White matter consists of nerve fibers covered by a substance (myelin) that insulates and protects the nerves. The leukoencephalopathy is thought to contribute to many of the neurological signs and symptoms in people with Sjgren-Larsson syndrome. Most affected individuals have intellectual disability that varies from mild to profound and is usually apparent by early childhood. People with Sjgren-Larsson syndrome have speech difficulties (dysarthria) and delayed speech. Usually they are able to produce only short sentences with poorly formed words. Rarely, people with this condition have normal intelligence. In addition, approximately 40 percent of people with Sjgren-Larsson syndrome have seizures.  Children with this condition often experience delayed development of motor skills (such as crawling and walking) due to abnormal muscle stiffness (spasticity) that is typically in their legs and, less commonly, also in their arms. About one-half of people with Sjgren-Larsson syndrome require wheelchair assistance and many others need some form of support to walk.  Affected individuals have tiny crystals in the light-sensitive tissue at the back of the eye (retina) that can be seen during an eye exam. Based on their appearance, these retinal crystals are often called glistening white dots. These white dots are usually apparent by early childhood, and it is unclear if they affect normal vision. People with Sjgren-Larsson syndrome may also have nearsightedness (myopia) or an increased sensitivity to light (photophobia).
Mutations in the ALDH3A2 gene cause Sjgren-Larsson syndrome. The ALDH3A2 gene provides instructions for making an enzyme called fatty aldehyde dehydrogenase (FALDH). The FALDH enzyme is part of a multistep process called fatty acid oxidation in which fats are broken down and converted into energy. Specifically, the FALDH enzyme breaks down molecules called fatty aldehydes to fatty acids.  ALDH3A2 gene mutations disrupt the normal process of fatty acid oxidation. Most mutations result in the production of a FALDH enzyme that is unable to break down fatty aldehyde molecules. As a result, fats that cannot be broken down build up in cells. Within skin cells, excess fat accumulation can interfere with the formation of membranes that act as protective barriers to control water loss. As a result of the loss of these protective barriers, the skin has difficulty maintaining its water balance, resulting in dry, scaly skin. In the brain, the consequences of excess fat accumulation are unclear, but it is likely that an abundance of fat disrupts the formation of myelin. Myelin is the covering that protects nerves and promotes the efficient transmission of nerve impulses. A lack of myelin can lead to neurological problems such as intellectual disability and walking difficulties. The cause of the eye problems is unclear, but it is also likely related to a disruption in the breakdown of fats.
CHMP2B-related frontotemporal dementia is a progressive brain disorder that affects personality, behavior, and language. The symptoms of this disorder usually become noticeable in a person's fifties or sixties, and affected people survive about 3 to 21 years after the appearance of symptoms.  Changes in personality and behavior are the most common early signs of CHMP2B-related frontotemporal dementia. These changes include inappropriate emotional responses, restlessness, loss of initiative, and neglect of personal hygiene. Affected individuals may overeat sweet foods or place non-food items into their mouths (hyperorality). Additionally, it may become difficult for affected individuals to interact with others in a socially appropriate manner. They increasingly require help with personal care and other activities of daily living.  Many people with CHMP2B-related frontotemporal dementia develop progressive problems with speech and language (aphasia). They may have trouble speaking, although they can often understand others' speech and written text. Affected individuals may also have difficulty using numbers (dyscalculia). In the later stages of the disease, many completely lose the ability to communicate.  Several years after signs and symptoms first appear, some people with CHMP2B-related frontotemporal dementia develop problems with movement. These movement abnormalities include rigidity, tremors, uncontrolled muscle tensing (dystonia), and involuntary muscle spasms (myoclonus). As the disease progresses, most affected individuals become unable to walk.
CHMP2B-related frontotemporal dementia results from mutations in the CHMP2B gene. This gene provides instructions for making a protein called charged multivesicular body protein 2B. This protein is active in the brain, where it plays an essential role in transporting proteins that need to be broken down (degraded).  Mutations in the CHMP2B gene lead to the production of an abnormal version of charged multivesicular body protein 2B. Most of the mutations that cause CHMP2B-related frontotemporal dementia result in the production of an abnormal protein that is missing a critical segment at one end. This segment keeps the protein turned off (inactive) when it is not needed. Without this segment, the protein is constantly turned on (active), which disrupts the transport and degradation of other proteins. These abnormalities ultimately lead to the death of nerve cells (neurons) in the brain.  A gradual loss of neurons throughout the brain is characteristic of CHMP2B-related frontotemporal dementia. Many of the features of this disease result from neuronal death in regions near the front of the brain called the frontal and temporal lobes. The frontal lobes are involved in reasoning, planning, judgment, and problem-solving, while the temporal lobes help process hearing, speech, memory, and emotion. It is unclear why the signs and symptoms of this disease are related primarily to the frontal and temporal lobes.
These resources address the diagnosis or management of CHMP2B-related frontotemporal dementia:  - Family Caregiver Alliance  - Gene Review: Gene Review: Frontotemporal Dementia, Chromosome 3-Linked  - Genetic Testing Registry: Frontotemporal Dementia, Chromosome 3-Linked   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
Tetrahydrobiopterin deficiency is a rare disorder characterized by a shortage (deficiency) of a molecule called tetrahydrobiopterin or BH4. This condition alters the levels of several substances in the body, including phenylalanine. Phenylalanine is a building block of proteins (an amino acid) that is obtained through the diet. It is found in foods that contain protein and in some artificial sweeteners. High levels of phenylalanine are present from early infancy in people with untreated tetrahydrobiopterin deficiency. This condition also alters the levels of chemicals called neurotransmitters, which transmit signals between nerve cells in the brain.  Infants with tetrahydrobiopterin deficiency appear normal at birth, but medical problems ranging from mild to severe become apparent over time. Signs and symptoms of this condition can include intellectual disability, progressive problems with development, movement disorders, difficulty swallowing, seizures, behavioral problems, and an inability to control body temperature.
This condition is rare, affecting an estimated 1 in 500,000 to 1 in 1 million newborns. In most parts of the world, tetrahydrobiopterin deficiency accounts for 1 to 3 percent of all cases of elevated phenylalanine levels. The remaining cases are caused by a similar condition called phenylketonuria (PKU). In certain countries, including Saudi Arabia, Taiwan, China, and Turkey, it is more common for elevated levels of phenylalanine to be caused by tetrahydrobiopterin deficiency than by PKU.
Tetrahydrobiopterin deficiency can be caused by mutations in one of several genes, including GCH1, PCBD1, PTS, and QDPR. These genes provide instructions for making enzymes that help produce and recycle tetrahydrobiopterin in the body. Tetrahydrobiopterin normally helps process several amino acids, including phenylalanine. It is also involved in the production of neurotransmitters.  If one of the enzymes fails to function correctly because of a gene mutation, little or no tetrahydrobiopterin is available to help process phenylalanine. As a result, phenylalanine can build up in the blood and other tissues. Because nerve cells in the brain are particularly sensitive to phenylalanine levels, excessive amounts of this substance can cause brain damage. Tetrahydrobiopterin deficiency can also alter the levels of certain neurotransmitters, which disrupts normal brain function. These abnormalities underlie the intellectual disability and other characteristic features of the condition.
These resources address the diagnosis or management of tetrahydrobiopterin deficiency:  - Baby's First Test: Biopterin Defect in Cofactor Biosynthesis  - Baby's First Test: Biopterin Defect in Cofactor Regeneration  - Genetic Testing Registry: 6-pyruvoyl-tetrahydropterin synthase deficiency  - Genetic Testing Registry: Dihydropteridine reductase deficiency  - Genetic Testing Registry: GTP cyclohydrolase I deficiency  - Genetic Testing Registry: Hyperphenylalaninemia, BH4-deficient, D  - MedlinePlus Encyclopedia: Serum Phenylalanine Screening   These resources from MedlinePlus offer information about the diagnosis and management of various health conditions:  - Diagnostic Tests  - Drug Therapy  - Surgery and Rehabilitation  - Genetic Counseling   - Palliative Care
Weissenbacher-Zweymller syndrome is a condition that affects bone growth. It is characterized by skeletal abnormalities, hearing loss, and distinctive facial features. This condition has features that are similar to those of another skeletal disorder, otospondylomegaepiphyseal dysplasia (OSMED).  Infants born with Weissenbacher-Zweymller syndrome are smaller than average because the bones in their arms and legs are unusually short. The thigh and upper arm bones are shaped like dumbbells, and the bones of the spine (vertebrae) may also be abnormally shaped. High-tone hearing loss occurs in some cases. Distinctive facial features include wide-set protruding eyes, a small, upturned nose with a flat bridge, and a small lower jaw. Some affected infants are born with an opening in the roof of the mouth (a cleft palate).  The skeletal features of Weissenbacher-Zweymller syndrome tend to diminish during childhood. Most adults with this condition are not unusually short, but do still retain the other features of Weissenbacher-Zweymller syndrome.
Mutations in the COL11A2 gene cause Weissenbacher-Zweymller syndrome. The COL11A2 gene is one of several genes that provide instructions for the production of type XI collagen. This type of collagen is important for the normal development of bones and other connective tissues that form the body's supportive framework. At least one mutation in the COL11A2 gene is known to cause Weissenbacher-Zweymller syndrome. This mutation disrupts the assembly of type XI collagen molecules, resulting in delayed bone development and the other features of this disorder.
Dystonia 6 is one of many forms of dystonia, which is a group of conditions characterized by involuntary movements, twisting (torsion) and tensing of various muscles, and unusual positioning of affected body parts. Dystonia 6 can appear at any age from childhood through adulthood; the average age of onset is 18.  The signs and symptoms of dystonia 6 vary among affected individuals. The disorder usually first impacts muscles of the head and neck, causing problems with speaking (dysarthria) and eating (dysphagia). Eyelid twitching (blepharospasm) may also occur. Involvement of one or more limbs is common, and in some cases occurs before the head and neck problems. Dystonia 6 gradually gets worse, and it may eventually involve most of the body.
Dystonia 6 is caused by mutations in the THAP1 gene. This gene provides instructions for making a protein that is a transcription factor, which means that it attaches (binds) to specific regions of DNA and regulates the activity of other genes. Through this function, it is thought to help control several processes in the body, including the growth and division (proliferation) of endothelial cells, which line the inside surface of blood vessels and other circulatory system structures called lymphatic vessels. The THAP1 protein also plays a role in the self-destruction of cells that are no longer needed (apoptosis).  Studies indicate that most of the THAP1 gene mutations that cause dystonia 6 affect the stability of the THAP1 protein, reducing the amount of functional THAP1 protein available for DNA binding. Other mutations may impair the protein's ability to bind with the correct regions of DNA. Problems with DNA binding likely disrupt the proper regulation of gene activity, leading to the signs and symptoms of dystonia 6.  A particular THAP1 gene mutation is specific to a Mennonite population in the Midwestern United States in which dystonia 6 was first described. This mutation changes the DNA sequence in a region of the gene known as exon 2. Some researchers use the term DYT6 dystonia to refer to dystonia caused by this particular mutation, and the broader term THAP1 dystonia to refer to dystonia caused by any THAP1 gene mutation. In general, mutations affecting the region of the THAP1 protein that binds to DNA, including the mutation found in the Mennonite population, tend to result in more severe signs and symptoms than mutations affecting other regions of the protein.
Spinal and bulbar muscular atrophy, also known as Kennedy disease, is a disorder of specialized nerve cells that control muscle movement (motor neurons). These nerve cells originate in the spinal cord and the part of the brain that is connected to the spinal cord (the brainstem).  Spinal and bulbar muscular atrophy mainly affects males and is characterized by muscle weakness and wasting (atrophy) that usually begins in adulthood and worsens slowly over time. Muscle wasting in the arms and legs results in cramping; leg muscle weakness can also lead to difficulty walking and a tendency to fall. Certain muscles in the face and throat (bulbar muscles) are also affected, which causes progressive problems with swallowing and speech. Additionally, muscle twitches (fasciculations) are common. Some males with the disorder experience unusual breast development (gynecomastia) and may be unable to father a child (infertile).
Spinal and bulbar muscular atrophy results from a particular type of mutation in the AR gene. This gene provides instructions for making a protein called an androgen receptor. This receptor attaches (binds) to a class of hormones called androgens, which are involved in male sexual development. Androgens and androgen receptors also have other important functions in both males and females, such as regulating hair growth and sex drive.  The AR gene mutation that causes spinal and bulbar muscular atrophy is the abnormal expansion of a DNA segment called a CAG triplet repeat. Normally, this DNA segment is repeated up to about 36 times. In people with spinal and bulbar muscular atrophy, the CAG segment is repeated at least 38 times, and it may be two or three times its usual length. Although the extended CAG region changes the structure of the androgen receptor, it is unclear how the altered protein disrupts nerve cells in the brain and spinal cord. Researchers believe that a fragment of the androgen receptor protein containing the CAG segment accumulates within these cells and interferes with normal cell functions. The nerve cells gradually die, leading to the muscle weakness and wasting seen in this condition. People with a higher number of CAG repeats tend to develop signs and symptoms of spinal and bulbar muscular atrophy at an earlier age.
This condition is inherited in an X-linked pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. In males (who have only one X chromosome), a mutation in the only copy of the gene in each cell causes the disorder. In most cases, males experience more severe symptoms of the disorder than females (who have two X chromosomes). Females with a mutation in one copy of the AR gene in each cell are typically unaffected. A few females with mutations in both copies of the gene have had mild features related to the condition, including muscle cramps and occasional tremors. Researchers believe that the milder signs and symptoms in females may be related to lower androgen levels.  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 spinal and bulbar muscular atrophy:  - Gene Review: Gene Review: Spinal and Bulbar Muscular Atrophy  - Genetic Testing Registry: Bulbo-spinal atrophy X-linked  - MedlinePlus Encyclopedia: Muscle Atrophy   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
MPV17-related hepatocerebral mitochondrial DNA depletion syndrome is an inherited disorder that can cause liver disease and neurological problems. The signs and symptoms of this condition begin in infancy and typically include vomiting, diarrhea, and an inability to grow or gain weight at the expected rate (failure to thrive). Many affected infants have a buildup of a chemical called lactic acid in the body (lactic acidosis) and low blood sugar (hypoglycemia). Within the first weeks of life, infants develop liver disease that quickly progresses to liver failure. The liver is frequently enlarged (hepatomegaly) and liver cells often have a reduced ability to release a digestive fluid called bile (cholestasis). Rarely, affected children develop liver cancer. After the onset of liver disease, many affected infants develop neurological problems, which can include developmental delay, weak muscle tone (hypotonia), and reduced sensation in the limbs (peripheral neuropathy). Individuals with MPV17-related hepatocerebral mitochondrial DNA depletion syndrome typically survive only into infancy or early childhood.  MPV17-related hepatocerebral mitochondrial DNA depletion syndrome is most frequently seen in the Navajo population of the southwestern United States. In this population, the condition is known as Navajo neurohepatopathy. People with Navajo neurohepatopathy tend to have a longer life expectancy than those with MPV17-related hepatocerebral mitochondrial DNA depletion syndrome. In addition to the signs and symptoms described above, people with Navajo neurohepatopathy may have problems with sensing pain that can lead to painless bone fractures and self-mutilation of the fingers or toes. Individuals with Navajo neurohepatopathy may lack feeling in the clear front covering of the eye (corneal anesthesia), which can lead to open sores and scarring on the cornea, resulting in impaired vision. The cause of these additional features is unknown.
As the condition name suggests, mutations in the MPV17 gene cause MPV17-related hepatocerebral mitochondrial DNA depletion syndrome. The protein produced from the MPV17 gene is located in the inner membrane of cell structures called mitochondria. Mitochondria are involved in a wide variety of cellular activities, including energy production, chemical signaling, and regulation of cell growth, division, and death. Mitochondria contain their own DNA, known as mitochondrial DNA (mtDNA), which is essential for the normal function of these structures. It is likely that the MPV17 protein is involved in the maintenance of mtDNA. Having an adequate amount of mtDNA is essential for normal energy production within cells.  MPV17 gene mutations that cause MPV17-related hepatocerebral mitochondrial DNA depletion syndrome lead to production of a protein with impaired function. One mutation causes all cases of Navajo neurohepatopathy and results in the production of an unstable MPV17 protein that is quickly broken down. A dysfunctional or absent MPV17 protein leads to problems with the maintenance of mtDNA, which can cause a reduction in the amount of mtDNA (known as mitochondrial DNA depletion). Mitochondrial DNA depletion impairs mitochondrial function in many of the body's cells and tissues, particularly the brain, liver, and other tissues that have high energy requirements. Reduced mitochondrial function in the liver and brain lead to the liver failure and neurological dysfunction associated with MPV17-related hepatocerebral mitochondrial DNA depletion syndrome. Researchers suggest that the less mtDNA that is available in cells, the more severe the features of Navajo neurohepatopathy.