bowang0911/MedQuAD huggingface dataset:
Spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME) is a neurological condition that causes muscle weakness and wasting (atrophy) and a combination of seizures and uncontrollable muscle jerks (myoclonic epilepsy).  In individuals with SMA-PME, spinal muscular atrophy results from a loss of specialized nerve cells, called motor neurons, in the spinal cord and the part of the brain that is connected to the spinal cord (the brainstem). After a few years of normal development, affected children begin experiencing muscle weakness and atrophy in the lower limbs, causing difficulty walking and frequent falls. The muscles in the upper limbs are later affected, and soon the muscle weakness and atrophy spreads throughout the body. Once weakness reaches the muscles used for breathing and swallowing, it leads to life-threatening breathing problems and increased susceptibility to pneumonia.  A few years after the muscle weakness begins, affected individuals start to experience recurrent seizures (epilepsy). Most people with SMA-PME have a variety of seizure types. In addition to myoclonic epilepsy, they may have generalized tonic-clonic seizures (also known as grand mal seizures), which cause muscle rigidity, convulsions, and loss of consciousness. Affected individuals can also have absence seizures, which cause loss of consciousness for a short period that may or may not be accompanied by muscle jerks. In SMA-PME, seizures often increase in frequency over time and are usually not well-controlled with medication. Individuals with SMA-PME may also have episodes of rhythmic shaking (tremors), usually in the hands; these tremors are not thought to be related to epilepsy.  Some people with SMA-PME develop hearing loss caused by nerve damage in the inner ear (sensorineural hearing loss).  Individuals with SMA-PME have a shortened lifespan; they generally live into late childhood or early adulthood. The cause of death is often respiratory failure or pneumonia.
SMA-PME is caused by mutations in the ASAH1 gene. This gene provides instructions for making an enzyme called acid ceramidase. This enzyme is found in lysosomes, which are cell compartments that digest and recycle materials. Within lysosomes, acid ceramidase breaks down fats called ceramides into a fat called sphingosine and a fatty acid. These two breakdown products are recycled to create new ceramides for the body to use. Ceramides have several roles within cells. For example, they are a component of a fatty substance called myelin that insulates and protects nerve cells.  ASAH1 gene mutations that cause SMA-PME result in a reduction of acid ceramidase activity to a level less than one-third of normal. Inefficient breakdown of ceramides and impaired production of its breakdown products likely play a role in the nerve cell damage that leads to the features of SMA-PME, but the exact mechanism is unknown.
These resources address the diagnosis or management of spinal muscular atrophy with progressive myoclonic epilepsy:  - Genetic Testing Registry: Jankovic Rivera syndrome  - Muscular Dystrophy Association: Spinal Muscular Atrophy Types   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
Coats plus syndrome is an inherited condition characterized by an eye disorder called Coats disease plus abnormalities of the brain, bones, gastrointestinal system, and other parts of the body.  Coats disease affects the retina, which is the tissue at the back of the eye that detects light and color. The disorder causes blood vessels in the retina to be abnormally enlarged (dilated) and twisted. The abnormal vessels leak fluid, which can eventually cause the layers of the retina to separate (retinal detachment). These eye abnormalities often result in vision loss.  People with Coats plus syndrome also have brain abnormalities including abnormal deposits of calcium (calcification), the development of fluid-filled pockets called cysts, and loss of a type of brain tissue known as white matter (leukodystrophy). These brain abnormalities worsen over time, causing slow growth, movement disorders, seizures, and a decline in intellectual function.  Other features of Coats plus syndrome include low bone density (osteopenia), which causes bones to be fragile and break easily, and a shortage of red blood cells (anemia), which can lead to unusually pale skin (pallor) and extreme tiredness (fatigue). Affected individuals can also have serious or life-threatening complications including abnormal bleeding in the gastrointestinal tract, high blood pressure in the vein that supplies blood to the liver (portal hypertension), and liver failure. Less common features of Coats plus syndrome can include sparse, prematurely gray hair; malformations of the fingernails and toenails; and abnormalities of skin coloring (pigmentation), such as light brown patches called caf-au-lait spots.  Coats plus syndrome and a disorder called leukoencephalopathy with calcifications and cysts (LCC; also called Labrune syndrome) have sometimes been grouped together under the umbrella term cerebroretinal microangiopathy with calcifications and cysts (CRMCC) because they feature very similar brain abnormalities. However, researchers recently found that Coats plus syndrome and LCC have different genetic causes, and they are now generally described as separate disorders instead of variants of a single condition.
Coats plus syndrome results from mutations in the CTC1 gene. This gene provides instructions for making a protein that plays an important role in structures known as telomeres, which are found at the ends of chromosomes. Telomeres are short, repetitive segments of DNA that help protect chromosomes from abnormally sticking together or breaking down (degrading). In most cells, telomeres become progressively shorter as the cell divides. After a certain number of cell divisions, the telomeres become so short that they trigger the cell to stop dividing or to self-destruct (undergo apoptosis). The CTC1 protein works as part of a group of proteins known as the CST complex, which is involved in the copying (replication) of telomeres. The CST complex helps prevent telomeres from being degraded in some cells as the cells divide.  Mutations in the CTC1 gene impair the function of the CST complex, which affects the replication of telomeres. However, it is unclear how CTC1 gene mutations impact telomere structure and function. Some studies have found that people with CTC1 gene mutations have abnormally short telomeres, while other studies have found no change in telomere length. Researchers are working to determine how telomeres are different in people with CTC1 gene mutations and how these changes could underlie the varied signs and symptoms of Coats plus syndrome.
Retinoblastoma is a rare type of eye cancer that usually develops in early childhood, typically before the age of 5. This form of cancer develops in the retina, which is the specialized light-sensitive tissue at the back of the eye that detects light and color.  In most children with retinoblastoma, the disease affects only one eye. However, one out of three children with retinoblastoma develops cancer in both eyes. The most common first sign of retinoblastoma is a visible whiteness in the pupil called "cat's eye reflex" or leukocoria. This unusual whiteness is particularly noticeable in photographs taken with a flash. Other signs and symptoms of retinoblastoma include crossed eyes or eyes that do not point in the same direction (strabismus); persistent eye pain, redness, or irritation; and blindness or poor vision in the affected eye(s).  Retinoblastoma is often curable when it is diagnosed early. However, if it is not treated promptly, this cancer can spread beyond the eye to other parts of the body. This advanced form of retinoblastoma can be life-threatening.  When retinoblastoma is associated with a gene mutation that occurs in all of the body's cells, it is known as germinal retinoblastoma. People with this form of retinoblastoma also have an increased risk of developing several other cancers outside the eye. Specifically, they are more likely to develop a cancer of the pineal gland in the brain (pinealoma), a type of bone cancer known as osteosarcoma, cancers of soft tissues such as muscle, and an aggressive form of skin cancer called melanoma.
Mutations in the RB1 gene are responsible for most cases of retinoblastoma. RB1 is a tumor suppressor gene, which means that it normally regulates cell growth and keeps cells from dividing too rapidly or in an uncontrolled way. Most mutations in the RB1 gene prevent it from making any functional protein, so it is unable to regulate cell division effectively. As a result, certain cells in the retina can divide uncontrollably to form a cancerous tumor. Some studies suggest that additional genetic changes can influence the development of retinoblastoma; these changes may help explain variations in the development and growth of tumors in different people.  A small percentage of retinoblastomas are caused by deletions in the region of chromosome 13 that contains the RB1 gene. Because these chromosomal changes involve several genes in addition to RB1, affected children usually also have intellectual disability, slow growth, and distinctive facial features (such as prominent eyebrows, a short nose with a broad nasal bridge, and ear abnormalities).
Researchers estimate that 40 percent of all retinoblastomas are germinal, which means that RB1 mutations occur in all of the body's cells, including reproductive cells (sperm or eggs). People with germinal retinoblastoma may have a family history of the disease, and they are at risk of passing on the mutated RB1 gene to the next generation. The other 60 percent of retinoblastomas are non-germinal, which means that RB1 mutations occur only in the eye and cannot be passed to the next generation.  In germinal retinoblastoma, mutations in the RB1 gene appear to be inherited in an autosomal dominant pattern. Autosomal dominant inheritance suggests that one copy of the altered gene in each cell is sufficient to increase cancer risk. A person with germinal retinoblastoma may inherit an altered copy of the gene from one parent, or the altered gene may be the result of a new mutation that occurs in an egg or sperm cell or just after fertilization. For retinoblastoma to develop, a mutation involving the other copy of the RB1 gene must occur in retinal cells during the person's lifetime. This second mutation usually occurs in childhood, typically leading to the development of retinoblastoma in both eyes.  In the non-germinal form of retinoblastoma, typically only one eye is affected and there is no family history of the disease. Affected individuals are born with two normal copies of the RB1 gene. Then, usually in early childhood, both copies of the RB1 gene in retinal cells acquire mutations or are lost. People with non-germinal retinoblastoma are not at risk of passing these RB1 mutations to their children. However, without genetic testing it can be difficult to tell whether a person with retinoblastoma in one eye has the germinal or the non-germinal form of the disease.
These resources address the diagnosis or management of retinoblastoma:  - Gene Review: Gene Review: Retinoblastoma  - Genetic Testing Registry: Retinoblastoma  - Genomics Education Programme (UK)  - MedlinePlus Encyclopedia: Retinoblastoma  - National Cancer Institute: Genetic Testing for Hereditary Cancer Syndromes   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
Donohue syndrome is a rare disorder characterized by severe insulin resistance, a condition in which the body's tissues and organs do not respond properly to the hormone insulin. Insulin normally helps regulate blood sugar levels by controlling how much sugar (in the form of glucose) is passed from the bloodstream into cells to be used as energy. Severe insulin resistance leads to problems with regulating blood sugar levels and affects the development and function of organs and tissues throughout the body.  Severe insulin resistance underlies the varied signs and symptoms of Donohue syndrome. Individuals with Donohue syndrome are unusually small starting before birth, and affected infants experience failure to thrive, which means they do not grow and gain weight at the expected rate. Additional features that become apparent soon after birth include a lack of fatty tissue under the skin (subcutaneous fat); wasting (atrophy) of muscles; excessive body hair growth (hirsutism); multiple cysts on the ovaries in females; and enlargement of the nipples, genitalia, kidneys, heart, and other organs. Most affected individuals also have a skin condition called acanthosis nigricans, in which the skin in body folds and creases becomes thick, dark, and velvety. Distinctive facial features in people with Donohue syndrome include bulging eyes, thick lips, upturned nostrils, and low-set ears. Affected individuals develop recurrent, life-threatening infections beginning in infancy.  Donohue syndrome is one of a group of related conditions described as inherited severe insulin resistance syndromes. These disorders, which also include Rabson-Mendenhall syndrome and type A insulin resistance syndrome, are considered part of a spectrum. Donohue syndrome represents the most severe end of the spectrum; most children with this condition do not survive beyond age 2.
Donohue syndrome results from mutations in the INSR gene. This gene provides instructions for making a protein called an insulin receptor, which is found in many types of cells. Insulin receptors are embedded in the outer membrane surrounding the cell, where they attach (bind) to insulin circulating in the bloodstream. This binding triggers signaling pathways that influence many cell functions.  The INSR gene mutations that cause Donohue syndrome greatly reduce the number of insulin receptors that reach the cell membrane or disrupt the function of these receptors. Although insulin is present in the bloodstream, without functional receptors it cannot exert its effects on cells and tissues. This severe resistance to the effects of insulin impairs blood sugar regulation and affects many aspects of development in people with Donohue syndrome.
Amelogenesis imperfecta is a disorder of tooth development. This condition causes teeth to be unusually small, discolored, pitted or grooved, and prone to rapid wear and breakage. Other dental abnormalities are also possible. These defects, which vary among affected individuals, can affect both primary (baby) teeth and permanent (adult) teeth.  Researchers have described at least 14 forms of amelogenesis imperfecta. These types are distinguished by their specific dental abnormalities and by their pattern of inheritance. Additionally, amelogenesis imperfecta can occur alone without any other signs and symptoms or it can occur as part of a syndrome that affects multiple parts of the body.
Mutations in the AMELX, ENAM, MMP20, and FAM83H genes can cause amelogenesis imperfecta. The AMELX, ENAM, and MMP20 genes provide instructions for making proteins that are essential for normal tooth development. Most of these proteins are involved in the formation of enamel, which is the hard, calcium-rich material that forms the protective outer layer of each tooth. Although the function of the protein produced from the FAM83H gene is unknown, it is also believed to be involved in the formation of enamel. Mutations in any of these genes result in altered protein structure or prevent the production of any protein. As a result, tooth enamel is abnormally thin or soft and may have a yellow or brown color. Teeth with defective enamel are weak and easily damaged.  Mutations in the genes described above account for only about half of all cases of the condition, with FAM83H gene mutations causing the majority of these cases. In the remaining cases, the genetic cause has not been identified. Researchers are working to find mutations in other genes that are involved in this disorder.
Amelogenesis imperfecta can have different inheritance patterns depending on the gene that is altered. Many cases are caused by mutations in the FAM83H gene and are inherited in an autosomal dominant pattern. This type of inheritance means one copy of the altered gene in each cell is sufficient to cause the disorder. Some cases caused by mutations in the ENAM gene also have an autosomal dominant inheritance pattern.  Amelogenesis imperfecta can also be inherited in an autosomal recessive pattern; this form of the disorder can result from mutations in the ENAM or MMP20 gene. Autosomal recessive inheritance means two copies of the gene in each cell are altered. 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.  About 5 percent of amelogenesis imperfecta cases are caused by mutations in the AMELX gene and are 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 most cases, males with X-linked amelogenesis imperfecta experience more severe dental abnormalities than females with this form of this condition.  Other cases of amelogenesis imperfecta result from new gene mutations and occur in people with no history of the disorder in their family.
These resources address the diagnosis or management of amelogenesis imperfecta:  - Genetic Testing Registry: Amelogenesis imperfecta - hypoplastic autosomal dominant - local  - Genetic Testing Registry: Amelogenesis imperfecta, hypocalcification type  - Genetic Testing Registry: Amelogenesis imperfecta, type 1E  - Genetic Testing Registry: Amelogenesis imperfecta, type IC  - MedlinePlus Encyclopedia: Amelogenesis imperfecta  - MedlinePlus Encyclopedia: Tooth - Abnormal Colors   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
Roberts syndrome is a genetic disorder characterized by limb and facial abnormalities. Affected individuals also grow slowly before and after birth. Mild to severe intellectual impairment occurs in half of all people with Roberts syndrome.  Children with Roberts syndrome are born with abnormalities of all four limbs. They have shortened arm and leg bones (hypomelia), particularly the bones in their forearms and lower legs. In severe cases, the limbs may be so short that the hands and feet are located very close to the body (phocomelia). People with Roberts syndrome may also have abnormal or missing fingers and toes, and joint deformities (contractures) commonly occur at the elbows and knees. The limb abnormalities are very similar on the right and left sides of the body, but arms are usually more severely affected than legs.  Individuals with Roberts syndrome typically have numerous facial abnormalities, including an opening in the lip (a cleft lip) with or without an opening in the roof of the mouth (cleft palate), a small chin (micrognathia), ear abnormalities, wide-set eyes (hypertelorism), outer corners of the eyes that point downward (down-slanting palpebral fissures), small nostrils, and a beaked nose. They may have a small head size (microcephaly), and in severe cases affected individuals have a sac-like protrusion of the brain (encephalocele) at the front of their head. In addition, people with Roberts syndrome may have heart, kidney, and genital abnormalities.  Infants with a severe form of Roberts syndrome are often stillborn or die shortly after birth. Mildly affected individuals may live into adulthood. A condition called SC phocomelia syndrome was originally thought to be distinct from Roberts syndrome; however, it is now considered to be a mild variant. "SC" represents the first letters of the surnames of the two families first diagnosed with this disorder.
Mutations in the ESCO2 gene cause Roberts syndrome. This gene provides instructions for making a protein that is important for proper chromosome separation during cell division. Before cells divide, they must copy all of their chromosomes. The copied DNA from each chromosome is arranged into two identical structures, called sister chromatids. The ESCO2 protein plays an important role in establishing the glue that holds the sister chromatids together until the chromosomes are ready to separate.  All identified mutations in the ESCO2 gene prevent the cell from producing any functional ESCO2 protein, which causes some of the glue between sister chromatids to be missing around the chromosome's constriction point (centromere). In Roberts syndrome, cells respond to abnormal sister chromatid attachment by delaying cell division. Delayed cell division can be a signal that the cell should undergo self-destruction. The signs and symptoms of Roberts syndrome may result from the loss of cells from various tissues during early development. Because both mildly and severely affected individuals lack any functional ESCO2 protein, the underlying cause of the variation in disease severity remains unknown. Researchers suspect that other genetic and environmental factors may be involved.
These resources address the diagnosis or management of Roberts syndrome:  - Gene Review: Gene Review: Roberts Syndrome  - Genetic Testing Registry: Roberts-SC phocomelia syndrome  - MedlinePlus Encyclopedia: Contracture deformity  - MedlinePlus Encyclopedia: Microcephaly   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
Familial paroxysmal nonkinesigenic dyskinesia is a disorder of the nervous system that causes periods of involuntary movement. Paroxysmal indicates that the abnormal movements come and go over time. Nonkinesigenic means that episodes are not triggered by sudden movement. Dyskinesia broadly refers to involuntary movement of the body.  People with familial paroxysmal nonkinesigenic dyskinesia experience episodes of abnormal movement that develop without a known cause or are brought on by alcohol, caffeine, stress, fatigue, menses, or excitement. Episodes are not induced by exercise or sudden movement and do not occur during sleep. An episode is characterized by irregular, jerking or shaking movements that range from mild to severe. In this disorder, the dyskinesias can include slow, prolonged contraction of muscles (dystonia); small, fast, "dance-like" motions (chorea); writhing movements of the limbs (athetosis); and, rarely, flailing movements of the limbs (ballismus). Dyskinesias also affect muscles in the trunk and face. The type of abnormal movement varies among affected individuals, even among members of the same family. Individuals with familial paroxysmal nonkinesigenic dyskinesia do not lose consciousness during an episode. Most people do not experience any other neurological symptoms between episodes.  Individuals with familial paroxysmal nonkinesigenic dyskinesia usually begin to show signs and symptoms of the disorder during childhood or their early teens. Episodes typically last 1-4 hours, and the frequency of episodes ranges from several per day to one per year. In some affected individuals, episodes occur less often with age.