Druvith/medqa1 huggingface dataset:
Question:  What is (are) dihydropyrimidine dehydrogenase deficiency ?
Answer: Dihydropyrimidine dehydrogenase deficiency is a disorder characterized by a wide range of severity, with neurological problems in some individuals and no signs or symptoms in others.  In people with severe dihydropyrimidine dehydrogenase deficiency, the disorder becomes apparent in infancy. These affected individuals have neurological problems such as recurrent seizures (epilepsy), intellectual disability, a small head size (microcephaly), increased muscle tone (hypertonia), delayed development of motor skills such as walking, and autistic behaviors that affect communication and social interaction. Other affected individuals are asymptomatic, which means they do not have any signs or symptoms of the condition. Individuals with asymptomatic dihydropyrimidine dehydrogenase deficiency may be identified only by laboratory testing.  People with dihydropyrimidine dehydrogenase deficiency, including those who otherwise exhibit no symptoms, are vulnerable to severe, potentially life-threatening toxic reactions to certain drugs called fluoropyrimidines that are used to treat cancer. Common examples of these drugs are 5-fluorouracil and capecitabine. These drugs are not broken down efficiently by people with dihydropyrimidine dehydrogenase deficiency and build up to toxic levels in the body (fluoropyrimidine toxicity). Severe inflammation and ulceration of the lining of the gastrointestinal tract (mucositis) may occur, which can lead to signs and symptoms including mouth sores, abdominal pain, bleeding, nausea, vomiting, and diarrhea. Fluoropyrimidine toxicity may also lead to low numbers of white blood cells (neutropenia), which increases the risk of infections. It can also be associated with low numbers of platelets in the blood (thrombocytopenia), which impairs blood clotting and may lead to abnormal bleeding (hemorrhage). Redness, swelling, numbness, and peeling of the skin on the palms and soles (hand-foot syndrome); shortness of breath; and hair loss may also occur.
Question:  How many people are affected by dihydropyrimidine dehydrogenase deficiency ?
Answer: Severe dihydropyrimidine dehydrogenase deficiency, with its early-onset neurological symptoms, is a rare disorder. Its prevalence is unknown. However, between 2 and 8 percent of the general population may be vulnerable to toxic reactions to fluoropyrimidine drugs caused by otherwise asymptomatic dihydropyrimidine dehydrogenase deficiency.
Question:  What are the genetic changes related to dihydropyrimidine dehydrogenase deficiency ?
Answer: Dihydropyrimidine dehydrogenase deficiency is caused by mutations in the DPYD gene. This gene provides instructions for making an enzyme called dihydropyrimidine dehydrogenase, which is involved in the breakdown of molecules called uracil and thymine. Uracil and thymine are pyrimidines, which are one type of nucleotide. Nucleotides are building blocks of DNA, its chemical cousin RNA, and molecules such as ATP and GTP that serve as energy sources in the cell.  Mutations in the DPYD gene result in a lack (deficiency) of functional dihydropyrimidine dehydrogenase. Dihydropyrimidine dehydrogenase deficiency interferes with the breakdown of uracil and thymine, and results in excess quantities of these molecules in the blood, urine, and the fluid that surrounds the brain and spinal cord (cerebrospinal fluid). It is unclear how the excess uracil and thymine are related to the specific signs and symptoms of dihydropyrimidine dehydrogenase deficiency. Mutations that result in the absence (complete deficiency) of dihydropyrimidine dehydrogenase generally lead to more severe signs and symptoms than do mutations that lead to a partial deficiency of this enzyme.  Because fluoropyrimidine drugs are also broken down by the dihydropyrimidine dehydrogenase enzyme, deficiency of this enzyme leads to the drug buildup that causes fluoropyrimidine toxicity.
Question:  Is dihydropyrimidine dehydrogenase deficiency inherited ?
Answer: Dihydropyrimidine dehydrogenase deficiency is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Depending on the severity of these mutations, people with two mutated copies of the DPYD gene in each cell may exhibit the signs and symptoms of this disorder, or they may be generally asymptomatic but at risk for toxic reactions to fluoropyrimidine drugs.  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. However, people with one mutated copy of the DPYD gene in each cell may still experience toxic reactions to fluoropyrimidine drugs.
Question:  What are the treatments for dihydropyrimidine dehydrogenase deficiency ?
Answer: These resources address the diagnosis or management of dihydropyrimidine dehydrogenase deficiency:  - Genetic Testing Registry: Dihydropyrimidine dehydrogenase 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
Question:  What is (are) Frasier syndrome ?
Answer: Frasier syndrome is a condition that affects the kidneys and genitalia.  Frasier syndrome is characterized by kidney disease that begins in early childhood. Affected individuals have a condition called focal segmental glomerulosclerosis, in which scar tissue forms in some glomeruli, which are the tiny blood vessels in the kidneys that filter waste from blood. In people with Frasier syndrome, this condition often leads to kidney failure by adolescence.  Although males with Frasier syndrome have the typical male chromosome pattern (46,XY), they have gonadal dysgenesis, in which external genitalia do not look clearly male or clearly female (ambiguous genitalia) or the genitalia appear completely female. The internal reproductive organs (gonads) are typically undeveloped and referred to as streak gonads. These abnormal gonads are nonfunctional and often become cancerous, so they are usually removed surgically early in life.  Affected females usually have normal genitalia and gonads and have only the kidney features of the condition. Because they do not have all the features of the condition, females are usually given the diagnosis of isolated nephrotic syndrome.
Question:  How many people are affected by Frasier syndrome ?
Answer: Frasier syndrome is thought to be a rare condition; approximately 50 cases have been described in the scientific literature.
Question:  What are the genetic changes related to Frasier syndrome ?
Answer: Mutations in the WT1 gene cause Frasier syndrome. The WT1 gene provides instructions for making a protein that regulates the activity of other genes by attaching (binding) to specific regions of DNA. On the basis of this action, the WT1 protein is called a transcription factor. The WT1 protein plays a role in the development of the kidneys and gonads (ovaries in females and testes in males) before birth.  The WT1 gene mutations that cause Frasier syndrome lead to the production of a protein with an impaired ability to control gene activity and regulate the development of the kidneys and reproductive organs, resulting in the signs and symptoms of Frasier syndrome.  Frasier syndrome has features similar to another condition called Denys-Drash syndrome, which is also caused by mutations in the WT1 gene. Because these two conditions share a genetic cause and have overlapping features, some researchers have suggested that they are part of a spectrum and not two distinct conditions.
Question:  Is Frasier syndrome inherited ?
Answer: 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.
Question:  What are the treatments for Frasier syndrome ?
Answer: These resources address the diagnosis or management of Frasier syndrome:  - Genetic Testing Registry: Frasier syndrome  - MedlinePlus Encyclopedia: Focal Segmental Glomerulosclerosis  - MedlinePlus Encyclopedia: Nephrotic 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
Question:  What is (are) hyperlysinemia ?
Answer: Hyperlysinemia is an inherited condition characterized by elevated blood levels of the amino acid lysine, a building block of most proteins. Hyperlysinemia is caused by the shortage (deficiency) of the enzyme that breaks down lysine. Hyperlysinemia typically causes no health problems, and most people with elevated lysine levels are unaware that they have this condition. Rarely, people with hyperlysinemia have intellectual disability or behavioral problems. It is not clear whether these problems are due to hyperlysinemia or another cause.
Question:  How many people are affected by hyperlysinemia ?
Answer: The incidence of hyperlysinemia is unknown.
Question:  What are the genetic changes related to hyperlysinemia ?
Answer: Mutations in the AASS gene cause hyperlysinemia. The AASS gene provides instructions for making an enzyme called aminoadipic semialdehyde synthase. This enzyme performs two functions in the breakdown of lysine. First, the enzyme breaks down lysine to a molecule called saccharopine. It then breaks down saccharopine to a molecule called alpha-aminoadipate semialdehyde.  Mutations in the AASS gene that impair the breakdown of lysine result in elevated levels of lysine in the blood and urine. These increased levels of lysine do not appear to have any negative effects on the body.  When mutations in the AASS gene impair the breakdown of saccharopine, this molecule builds up in blood and urine. This buildup is sometimes referred to as saccharopinuria, which is considered to be a variant of hyperlysinemia. It is unclear if saccharopinuria causes any symptoms.
Question:  Is hyperlysinemia inherited ?
Answer: 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.
Question:  What are the treatments for hyperlysinemia ?
Answer: These resources address the diagnosis or management of hyperlysinemia:  - Genetic Testing Registry: Hyperlysinemia  - Genetic Testing Registry: Saccharopinuria   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
Question:  What is (are) Zellweger spectrum disorder ?
Answer: Zellweger spectrum disorder is a group of conditions that have overlapping signs and symptoms and affect many parts of the body. This group of conditions includes Zellweger syndrome, neonatal adrenoleukodystrophy (NALD), and infantile Refsum disease. These conditions were once thought to be distinct disorders but are now considered to be part of the same condition spectrum. Zellweger syndrome is the most severe form of the Zellweger spectrum disorder, NALD is intermediate in severity, and infantile Refsum disease is the least severe form. Because these three conditions are now considered one disorder, some researchers prefer not to use the separate condition names but to instead refer to cases as severe, intermediate, or mild.  Individuals with Zellweger syndrome, at the severe end of the spectrum, develop signs and symptoms of the condition during the newborn period. These infants experience weak muscle tone (hypotonia), feeding problems, hearing and vision loss, and seizures. These problems are caused by the breakdown of myelin, which is the covering that protects nerves and promotes the efficient transmission of nerve impulses. The part of the brain and spinal cord that contains myelin is called white matter. Destruction of myelin (demyelination) leads to loss of white matter (leukodystrophy). Children with Zellweger syndrome also develop life-threatening problems in other organs and tissues, such as the liver, heart, and kidneys. They may have skeletal abnormalities, including a large space between the bones of the skull (fontanels) and characteristic bone spots known as chondrodysplasia punctata that can be seen on x-ray. Affected individuals have distinctive facial features, including a flattened face, broad nasal bridge, and high forehead. Children with Zellweger syndrome typically do not survive beyond the first year of life.  People with NALD or infantile Refsum disease, which are at the less-severe end of the spectrum, have more variable features than those with Zellweger syndrome and usually do not develop signs and symptoms of the disease until late infancy or early childhood. They may have many of the features of Zellweger syndrome; however, their condition typically progresses more slowly. Children with these less-severe conditions often have hypotonia, vision problems, hearing loss, liver dysfunction, developmental delay, and some degree of intellectual disability. Most people with NALD survive into childhood, and those with infantile Refsum disease may reach adulthood. In rare cases, individuals at the mildest end of the condition spectrum have developmental delay in childhood and hearing loss or vision problems beginning in adulthood and do not develop the other features of this disorder.
Question:  How many people are affected by Zellweger spectrum disorder ?
Answer: Zellweger spectrum disorder is estimated to occur in 1 in 50,000 individuals.
Question:  What are the genetic changes related to Zellweger spectrum disorder ?
Answer: Mutations in at least 12 genes have been found to cause Zellweger spectrum disorder. These genes provide instructions for making a group of proteins known as peroxins, which are essential for the formation and normal functioning of cell structures called peroxisomes. Peroxisomes are sac-like compartments that contain enzymes needed to break down many different substances, including fatty acids and certain toxic compounds. They are also important for the production of fats (lipids) used in digestion and in the nervous system. Peroxins assist in the formation (biogenesis) of peroxisomes by producing the membrane that separates the peroxisome from the rest of the cell and by importing enzymes into the peroxisome.  Mutations in the genes that cause Zellweger spectrum disorder prevent peroxisomes from forming normally. Diseases that disrupt the formation of peroxisomes, including Zellweger spectrum disorder, are called peroxisome biogenesis disorders. If the production of peroxisomes is altered, these structures cannot perform their usual functions. The signs and symptoms of Zellweger syndrome are due to the absence of functional peroxisomes within cells. NALD and infantile Refsum disease are caused by mutations that allow some peroxisomes to form.  Mutations in the PEX1 gene are the most common cause of Zellweger spectrum disorder and are found in nearly 70 percent of affected individuals. The other genes associated with Zellweger spectrum disorder each account for a smaller percentage of cases of this condition.
Question:  Is Zellweger spectrum disorder inherited ?
Answer: 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.
Question:  What are the treatments for Zellweger spectrum disorder ?
Answer: These resources address the diagnosis or management of Zellweger spectrum disorder:  - Gene Review: Gene Review: Peroxisome Biogenesis Disorders, Zellweger Syndrome Spectrum  - Genetic Testing Registry: Infantile Refsum's disease  - Genetic Testing Registry: Neonatal adrenoleucodystrophy  - Genetic Testing Registry: Peroxisome biogenesis disorders, Zellweger syndrome spectrum  - Genetic Testing Registry: Zellweger syndrome  - MedlinePlus Encyclopedia: Seizures   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
Question:  What is (are) Swyer syndrome ?
Answer: Swyer syndrome is a condition that affects sexual development. Sexual development is usually determined by an individual's chromosomes; however, in Swyer syndrome, sexual development does not match the affected individual's chromosomal makeup.  People usually have 46 chromosomes in each cell. Two of the 46 chromosomes, known as X and Y, are called sex chromosomes because they help determine whether a person will develop male or female sex characteristics. Girls and women typically have two X chromosomes (46,XX karyotype), while boys and men usually have one X chromosome and one Y chromosome (46,XY karyotype). In Swyer syndrome, individuals with one X chromosome and one Y chromosome in each cell, the pattern typically found in boys and men, have female reproductive structures.  People with Swyer syndrome have typical female external genitalia. The uterus and fallopian tubes are normally-formed, but the gonads (ovaries or testes) are not functional; affected individuals have undeveloped clumps of tissue called streak gonads. Because of the lack of development of the gonads, Swyer syndrome is also called 46,XY complete gonadal dysgenesis. The residual gonadal tissue often becomes cancerous, so it is usually removed surgically early in life.  People with Swyer syndrome are typically raised as girls and have a female gender identity. Because they do not have functional ovaries, affected individuals usually begin hormone replacement therapy during adolescence to induce menstruation and development of female secondary sex characteristics such as breast enlargement and uterine growth. Hormone replacement therapy also helps reduce the risk of reduced bone density (osteopenia and osteoporosis). Women with this disorder do not produce eggs (ova), but they may be able to become pregnant with a donated egg or embryo.  Swyer syndrome usually affects only sexual development; such cases are called isolated Swyer syndrome. However, depending on the genetic cause, Swyer syndrome may also occur along with health conditions such as nerve problems (neuropathy) or as part of a syndrome such as campomelic dysplasia, which causes severe skeletal abnormalities.
Question:  How many people are affected by Swyer syndrome ?
Answer: Swyer syndrome occurs in approximately 1 in 80,000 people.
Question:  What are the genetic changes related to Swyer syndrome ?
Answer: Mutations in the SRY gene have been identified in approximately 15 percent of individuals with Swyer syndrome. The SRY gene, located on the Y chromosome, provides instructions for making the sex-determining region Y protein. This protein is a transcription factor, which means it attaches (binds) to specific regions of DNA and helps control the activity of particular genes. The sex-determining region Y protein starts processes that are involved in male sexual development. These processes cause a fetus to develop male gonads (testes) and prevent the development of female reproductive structures (uterus and fallopian tubes). SRY gene mutations that cause Swyer syndrome prevent production of the sex-determining region Y protein or result in the production of a nonfunctioning protein. A fetus whose cells do not produce functional sex-determining region Y protein will not develop testes but will develop a uterus and fallopian tubes, despite having a typically male karyotype.  Swyer syndrome can also be caused by mutations in the MAP3K1 gene; research indicates that mutations in this gene may account for up to 18 percent of cases. The MAP3K1 gene provides instructions for making a protein that helps regulate signaling pathways that control various processes in the body. These include the processes of determining sexual characteristics before birth. The mutations in this gene that cause Swyer syndrome decrease signaling that leads to male sexual differentiation and enhance signaling that leads to female sexual differentiation, preventing the development of testes and allowing the development of a uterus and fallopian tubes.  Mutations in the DHH and NR5A1 genes have also been identified in small numbers of people with Swyer syndrome. The DHH gene provides instructions for making a protein that is important for early development of tissues in many parts of the body. The NR5A1 gene provides instructions for producing another transcription factor called the steroidogenic factor 1 (SF1). This protein helps control the activity of several genes related to the production of sex hormones and sexual differentiation. Mutations in the DHH and NR5A1 genes affect the process of sexual differentiation, preventing affected individuals with a typically male karyotype from developing testes and causing them to develop a uterus and fallopian tubes.  Changes affecting other genes have also been identified in a small number of people with Swyer syndrome. Nongenetic factors, such as hormonal medications taken by the mother during pregnancy, have also been associated with this condition. However, in most individuals with Swyer syndrome, the cause is unknown.
Question:  Is Swyer syndrome inherited ?
Answer: Most cases of Swyer syndrome are not inherited; they occur in people with no history of the condition in their family. These cases result either from nongenetic causes or from new (de novo) mutations in a gene that occur during the formation of reproductive cells (eggs or sperm) or in early embryonic development.  SRY-related Swyer syndrome is usually caused by a new mutation. However, some individuals with Swyer syndrome inherit an altered SRY gene from an unaffected father who is mosaic for the mutation. Mosaic means that an individual has the mutation in some cells (including some reproductive cells) but not in others. In rare cases, a father may carry the mutation in every cell of the body but also has other genetic variations that prevent him from being affected by the condition. Because the SRY gene is on the Y chromosome, Swyer syndrome caused by SRY gene mutations is described as having a Y-linked inheritance pattern.  When Swyer syndrome is associated with an MAP3K1 or NR5A1 gene mutation, the condition is also usually caused by a new mutation. In the rare inherited cases, the mutation may be inherited from either parent, since these genes are not on the Y chromosome. In these cases, the condition has an autosomal dominant pattern of inheritance, which means one copy of the altered gene in each cell is sufficient to cause the condition.  Swyer syndrome caused by mutations in the DHH gene 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 are carriers of one copy of the altered gene. Female carriers of a DHH gene mutation generally have typical sex development. Male carriers of a DHH gene mutation may also be unaffected, or they may have genital differences such as the urethra opening on the underside of the penis (hypospadias).
Question:  What are the treatments for Swyer syndrome ?
Answer: These resources address the diagnosis or management of Swyer syndrome:  - Gene Review: Gene Review: 46,XY Disorder of Sex Development and 46,XY Complete Gonadal Dysgenesis  - Genetic Testing Registry: Pure gonadal dysgenesis 46,XY  - MedlinePlus Encyclopedia: Intersex  - University College London Hospitals: Disorders of Sexual Development   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