bowang0911/MedQuAD huggingface dataset:
Bietti crystalline dystrophy is caused by mutations in the CYP4V2 gene. This gene provides instructions for making a member of the cytochrome P450 family of enzymes. These enzymes are involved in the formation and breakdown of various molecules and chemicals within cells. The CYP4V2 enzyme is involved in a multi-step process called fatty acid oxidation in which lipids are broken down and converted into energy, but the enzyme's specific function is not well understood. CYP4V2 gene mutations that cause Bietti crystalline dystrophy impair or eliminate the function of this enzyme and are believed to affect lipid breakdown. However, it is unknown how they lead to the specific signs and symptoms of Bietti crystalline dystrophy. For unknown reasons, the severity of the signs and symptoms differs significantly among individuals with the same CYP4V2 gene mutation.
These resources address the diagnosis or management of Bietti crystalline dystrophy:  - Gene Review: Gene Review: Bietti Crystalline Dystrophy  - Genetic Testing Registry: Bietti crystalline corneoretinal dystrophy   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
Pallister-Killian mosaic syndrome is a developmental disorder that affects many parts of the body. This condition is characterized by extremely weak muscle tone (hypotonia) in infancy and early childhood, intellectual disability, distinctive facial features, sparse hair, areas of unusual skin coloring (pigmentation), and other birth defects.  Most babies with Pallister-Killian mosaic syndrome are born with significant hypotonia, which can cause difficulty breathing and problems with feeding. Hypotonia also interferes with the normal development of motor skills such as sitting, standing, and walking. About 30 percent of affected individuals are ultimately able to walk without assistance. Additional developmental delays result from intellectual disability, which is usually severe to profound. Speech is often limited or absent in people with this condition.  Pallister-Killian mosaic syndrome is associated with a distinctive facial appearance that is often described as "coarse." Characteristic facial features include a high, rounded forehead; a broad nasal bridge; a short nose; widely spaced eyes; low-set ears; rounded cheeks; and a wide mouth with a thin upper lip and a large tongue. Some affected children are born with an opening in the roof of the mouth (cleft palate) or a high arched palate.  Most children with Pallister-Killian mosaic syndrome have sparse hair on their heads, particularly around the temples. These areas may fill in as affected children get older. Many affected individuals also have streaks or patches of skin that are darker or lighter than the surrounding skin. These skin changes can occur anywhere on the body, and they may be apparent at birth or occur later in life.  Additional features of Pallister-Killian mosaic syndrome can include hearing loss, vision impairment, seizures, extra nipples, genital abnormalities, and heart defects. Affected individuals may also have skeletal abnormalities such as extra fingers and/or toes, large big toes (halluces), and unusually short arms and legs. About 40 percent of affected infants are born with a congenital diaphragmatic hernia, which is a hole in the muscle that separates the abdomen from the chest cavity (the diaphragm). This potentially serious birth defect allows the stomach and intestines to move into the chest, where they can crowd the developing heart and lungs.  The signs and symptoms of Pallister-Killian mosaic syndrome vary, although most people with this disorder have severe to profound intellectual disability and other serious health problems. The most severe cases involve birth defects that are life-threatening in early infancy. However, several affected people have had milder features, including mild intellectual disability and less noticeable physical abnormalities.
Pallister-Killian mosaic syndrome is usually caused by the presence of an abnormal extra chromosome called an isochromosome 12p or i(12p). An isochromosome is a chromosome with two identical arms. Normal chromosomes have one long (q) arm and one short (p) arm, but isochromosomes have either two q arms or two p arms. Isochromosome 12p is a version of chromosome 12 made up of two p arms.  Cells normally have two copies of each chromosome, one inherited from each parent. In people with Pallister-Killian mosaic syndrome, cells have the two usual copies of chromosome 12, but some cells also have the isochromosome 12p. These cells have a total of four copies of all the genes on the p arm of chromosome 12. The extra genetic material from the isochromosome disrupts the normal course of development, causing the characteristic features of this disorder.  Although Pallister-Killian mosaic syndrome is usually caused by the presence of an isochromosome 12p, other, more complex chromosomal changes involving chromosome 12 are responsible for the disorder in rare cases.
Pallister-Killian mosaic syndrome is not inherited. The chromosomal change responsible for the disorder typically occurs as a random event during the formation of reproductive cells (eggs or sperm) in a parent of the affected individual, usually the mother. Affected individuals have no history of the disorder in their families.  An error in cell division called nondisjunction likely results in a reproductive cell containing an isochromosome 12p. If this atypical reproductive cell contributes to the genetic makeup of a child, the child will have two normal copies of chromosome 12 along with an isochromosome 12p.  As cells divide during early development, some cells lose the isochromosome 12p, while other cells retain the abnormal chromosome. This situation is called mosaicism. Almost all cases of Pallister-Killian mosaic syndrome are caused by mosaicism for an isochromosome 12p. If all of the body's cells contained the isochromosome, the resulting syndrome would probably not be compatible with life.
These resources address the diagnosis or management of Pallister-Killian mosaic syndrome:  - Genetic Testing Registry: Pallister-Killian syndrome  - MedlinePlus Encyclopedia: Chromosome  - MedlinePlus Encyclopedia: Mosaicism   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
Central core disease is a disorder that affects muscles used for movement (skeletal muscles). This condition causes muscle weakness that ranges from almost unnoticeable to very severe.  Most people with central core disease experience persistent, mild muscle weakness that does not worsen with time. This weakness affects the muscles near the center of the body (proximal muscles), particularly muscles in the upper legs and hips. Muscle weakness causes affected infants to appear "floppy" and can delay the development of motor skills such as sitting, standing, and walking. In severe cases, affected infants experience profoundly weak muscle tone (hypotonia) and serious or life-threatening breathing problems. Central core disease is also associated with skeletal abnormalities such as abnormal curvature of the spine (scoliosis), hip dislocation, and joint deformities called contractures that restrict the movement of certain joints.  Many people with central core disease also have an increased risk of developing a severe reaction to certain drugs used during surgery and other invasive procedures. This reaction is called malignant hyperthermia. Malignant hyperthermia occurs in response to some anesthetic gases, which are used to block the sensation of pain, and with a particular type of muscle relaxant. If given these drugs, people at risk for malignant hyperthermia may experience muscle rigidity, breakdown of muscle fibers (rhabdomyolysis), a high fever, increased acid levels in the blood and other tissues (acidosis), and a rapid heart rate. The complications of malignant hyperthermia can be life-threatening unless they are treated promptly.  Central core disease gets its name from disorganized areas called cores, which are found in the center of muscle fibers in many affected individuals. These abnormal regions can only be seen under a microscope. Although the presence of cores can help doctors diagnose central core disease, it is unclear how they are related to muscle weakness and the other features of this condition.
Mutations in the RYR1 gene cause central core disease.  The RYR1 gene provides instructions for making a protein called ryanodine receptor 1. This protein plays an essential role in skeletal muscles. For the body to move normally, these muscles must tense (contract) and relax in a coordinated way. Muscle contractions are triggered by the flow of charged atoms (ions) into muscle cells. The ryanodine receptor 1 protein forms a channel that releases calcium ions stored within muscle cells. The resulting increase in calcium ion concentration inside muscle cells stimulates muscle fibers to contract, allowing the body to move.  Mutations in the RYR1 gene change the structure of ryanodine receptor 1, allowing calcium ions to "leak" through the abnormal channel or impairing the channel's ability to release stored calcium ions at the correct time. This disruption in calcium ion transport prevents muscles from contracting normally, leading to the muscle weakness characteristic of central core disease.
Central core disease is most often inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In some cases, an affected person inherits the mutation from one affected parent. Other cases may result from new mutations in the gene. These cases occur in people with no history of the disorder in their family.  Less commonly, central core disease is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but typically do not show signs and symptoms of the condition. People who carry one mutated copy of the RYR1 gene, however, may be at increased risk for malignant hyperthermia.
These resources address the diagnosis or management of central core disease:  - Gene Review: Gene Review: Central Core Disease  - Genetic Testing Registry: Central core disease  - MedlinePlus Encyclopedia: Hypotonia  - MedlinePlus Encyclopedia: Malignant Hyperthermia   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
Naegeli-Franceschetti-Jadassohn syndrome/dermatopathia pigmentosa reticularis (NFJS/DPR) represents a rare type of ectodermal dysplasia, a group of about 150 conditions characterized by abnormal development of ectodermal tissues including the skin, hair, nails, teeth, and sweat glands. NFJS and DPR were originally described as separate conditions; however, because they have similar features and are caused by mutations in the same gene, they are now often considered forms of the same disorder.  Among the most common signs of NFJS/DPR is a net-like pattern of dark brown or gray skin coloring, known as reticulate hyperpigmentation. This darker pigmentation is seen most often on the neck, chest, and abdomen, although it can also occur in and around the eyes and mouth. Reticulate hyperpigmentation appears in infancy or early childhood. It may fade with age or persist throughout life.  NFJS/DPR also affects the skin on the hands and feet. The skin on the palms of the hands and soles of the feet often becomes thick, hard, and callused, a condition known as palmoplantar keratoderma. Some affected individuals also have blistering on their palms and soles. Their fingernails and toenails may be malformed, brittle, and either thicker or thinner than usual. Most affected individuals are missing the patterned ridges on the skin of the hands and feet, called dermatoglyphs, that are the basis for each person's unique fingerprints.  Additional features of NFJS/DPR can include a reduced ability to sweat (hypohidrosis) or excess sweating (hyperhidrosis) and dental abnormalities. Some affected individuals also have hair loss (alopecia) on the scalp, eyebrows, and underarms. The alopecia is described as noncicatricial because it does not leave scars (cicatrices).
NFJS/DPR results from mutations in the KRT14 gene. This gene provides instructions for making a protein called keratin 14. Keratins are tough, fibrous proteins that provide strength and resiliency to the outer layer of the skin (the epidermis). Researchers believe that keratin 14 may also play a role in the formation of sweat glands and the development of dermatoglyphs.  The KRT14 gene mutations that cause NFJS/DPR most likely reduce the amount of functional keratin 14 that is produced in cells. A shortage of this protein makes cells in the epidermis more likely to self-destruct (undergo apoptosis). The resulting loss of these cells alters the normal development and structure of ectodermal tissues, which likely underlies most of the skin and nail problems characteristic of NFJS/DPR. However, it is unclear how a shortage of keratin 14 is related to changes in skin pigmentation.
These resources address the diagnosis or management of NFJS/DPR:  - Foundation for Ichthyosis and Related Skin Types (FIRST): Palmoplantar Keratodermas  - Genetic Testing Registry: Dermatopathia pigmentosa reticularis  - Genetic Testing Registry: Naegeli-Franceschetti-Jadassohn syndrome  - MedlinePlus Encyclopedia: Ectodermal Dysplasia  - MedlinePlus Encyclopedia: Nail Abnormalities   These resources from MedlinePlus offer information about the diagnosis and management of various health conditions:  - Diagnostic Tests  - Drug Therapy  - Surgery and Rehabilitation  - Genetic Counseling   - Palliative Care
Fanconi anemia is a condition that affects many parts of the body. People with this condition may have bone marrow failure, physical abnormalities, organ defects, and an increased risk of certain cancers.  The major function of bone marrow is to produce new blood cells. These include red blood cells, which carry oxygen to the body's tissues; white blood cells, which fight infections; and platelets, which are necessary for normal blood clotting. Approximately 90 percent of people with Fanconi anemia have impaired bone marrow function that leads to a decrease in the production of all blood cells (aplastic anemia). Affected individuals experience extreme tiredness (fatigue) due to low numbers of red blood cells (anemia), frequent infections due to low numbers of white blood cells (neutropenia), and clotting problems due to low numbers of platelets (thrombocytopenia). People with Fanconi anemia may also develop myelodysplastic syndrome, a condition in which immature blood cells fail to develop normally.  More than half of people with Fanconi anemia have physical abnormalities. These abnormalities can involve irregular skin coloring such as unusually light-colored skin (hypopigmentation) or caf-au-lait spots, which are flat patches on the skin that are darker than the surrounding area. Other possible symptoms of Fanconi anemia include malformed thumbs or forearms and other skeletal problems including short stature; malformed or absent kidneys and other defects of the urinary tract; gastrointestinal abnormalities; heart defects; eye abnormalities such as small or abnormally shaped eyes; and malformed ears and hearing loss. People with this condition may have abnormal genitalia or malformations of the reproductive system. As a result, most affected males and about half of affected females cannot have biological children (are infertile). Additional signs and symptoms can include abnormalities of the brain and spinal cord (central nervous system), including increased fluid in the center of the brain (hydrocephalus) or an unusually small head size (microcephaly).  Individuals with Fanconi anemia have an increased risk of developing a cancer of blood-forming cells in the bone marrow called acute myeloid leukemia (AML) or tumors of the head, neck, skin, gastrointestinal system, or genital tract. The likelihood of developing one of these cancers in people with Fanconi anemia is between 10 and 30 percent.
Mutations in at least 15 genes can cause Fanconi anemia. Proteins produced from these genes are involved in a cell process known as the FA pathway. The FA pathway is turned on (activated) when the process of making new copies of DNA, called DNA replication, is blocked due to DNA damage. The FA pathway sends certain proteins to the area of damage, which trigger DNA repair so DNA replication can continue.  The FA pathway is particularly responsive to a certain type of DNA damage known as interstrand cross-links (ICLs). ICLs occur when two DNA building blocks (nucleotides) on opposite strands of DNA are abnormally attached or linked together, which stops the process of DNA replication. ICLs can be caused by a buildup of toxic substances produced in the body or by treatment with certain cancer therapy drugs.  Eight proteins associated with Fanconi anemia group together to form a complex known as the FA core complex. The FA core complex activates two proteins, called FANCD2 and FANCI. The activation of these two proteins brings DNA repair proteins to the area of the ICL so the cross-link can be removed and DNA replication can continue.  Eighty to 90 percent of cases of Fanconi anemia are due to mutations in one of three genes, FANCA, FANCC, and FANCG. These genes provide instructions for producing components of the FA core complex. Mutations in any of the many genes associated with the FA core complex will cause the complex to be nonfunctional and disrupt the entire FA pathway. As a result, DNA damage is not repaired efficiently and ICLs build up over time. The ICLs stall DNA replication, ultimately resulting in either abnormal cell death due to an inability make new DNA molecules or uncontrolled cell growth due to a lack of DNA repair processes. Cells that divide quickly, such as bone marrow cells and cells of the developing fetus, are particularly affected. The death of these cells results in the decrease in blood cells and the physical abnormalities characteristic of Fanconi anemia. When the buildup of errors in DNA leads to uncontrolled cell growth, affected individuals can develop acute myeloid leukemia or other cancers.
Fanconi anemia is most often 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.  Very rarely, this condition is inherited in an X-linked recessive pattern. The gene associated with X-linked recessive Fanconi anemia is located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation would have to occur in both copies of the gene to cause the disorder. Because it is unlikely that females will have two altered copies of this gene, males are affected by X-linked recessive disorders much more frequently than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.
These resources address the diagnosis or management of Fanconi anemia:  - Cincinnati Children's Hospital: Fanconi Anemia Comprehensive Care Center  - Fanconi Anemia Research Fund: Fanconi Anemia Guidelines for Diagnosis and Management  - Gene Review: Gene Review: Fanconi Anemia  - Genetic Testing Registry: Fanconi anemia  - Genetic Testing Registry: Fanconi anemia, complementation group A  - Genetic Testing Registry: Fanconi anemia, complementation group B  - Genetic Testing Registry: Fanconi anemia, complementation group C  - Genetic Testing Registry: Fanconi anemia, complementation group D1  - Genetic Testing Registry: Fanconi anemia, complementation group D2  - Genetic Testing Registry: Fanconi anemia, complementation group E  - Genetic Testing Registry: Fanconi anemia, complementation group F  - Genetic Testing Registry: Fanconi anemia, complementation group G  - Genetic Testing Registry: Fanconi anemia, complementation group I  - Genetic Testing Registry: Fanconi anemia, complementation group J  - Genetic Testing Registry: Fanconi anemia, complementation group L  - Genetic Testing Registry: Fanconi anemia, complementation group M  - Genetic Testing Registry: Fanconi anemia, complementation group N  - Genetic Testing Registry: Fanconi anemia, complementation group O  - Genetic Testing Registry: Fanconi anemia, complementation group P  - MedlinePlus Encyclopedia: Fanconi's Anemia  - National Cancer Institute: Adult Acute Myeloid Leukemia Treatment PDQ  - National Cancer Institute: Myelodysplastic Syndromes Treatment PDQ  - National Heart Lung and Blood Institute: How is Fanconi Anemia Treated?  - The Rockefeller University: International Fanconi Anemia Registry   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
18q deletion syndrome is a chromosomal condition that results when a piece of chromosome 18 is missing. The condition can lead to a wide variety of signs and symptoms among affected individuals.  Most people with 18q deletion syndrome have intellectual disability and delayed development that can range from mild to severe, but some affected individuals have normal intelligence and development. Seizures, hyperactivity, aggression, and autistic behaviors that affect communication and social interaction may also occur. Some people with 18q deletion syndrome have a loss of tissue called white matter in the brain and spinal cord (leukodystrophy), structural abnormalities of the brain, or an abnormally small head size (microcephaly).  Other features that are common in 18q deletion syndrome include short stature, weak muscle tone (hypotonia), narrow auditory canals leading to hearing loss, and limb abnormalities such as foot deformities and thumbs that are positioned unusually close to the wrist. Some affected individuals have mild facial differences such as deep-set eyes, a flat or sunken appearance of the middle of the face (midface hypoplasia), a wide mouth, and prominent ears; these features are often not noticeable except in a detailed medical evaluation. Eye movement disorders and other vision problems, genital abnormalities, heart disease, and skin problems may also occur in this disorder.