bowang0911/MedQuAD huggingface dataset:
Pseudocholinesterase deficiency can be caused by mutations in the BCHE gene. This gene provides instructions for making the pseudocholinesterase enzyme, also known as butyrylcholinesterase, which is produced by the liver and circulates in the blood. The pseudocholinesterase enzyme is involved in the breakdown of choline ester drugs. It is likely that the enzyme has other functions in the body, but these functions are not well understood. Studies suggest that the enzyme may be involved in the transmission of nerve signals.  Some BCHE gene mutations that cause pseudocholinesterase deficiency result in an abnormal pseudocholinesterase enzyme that does not function properly. Other mutations prevent the production of the pseudocholinesterase enzyme. A lack of functional pseudocholinesterase enzyme impairs the body's ability to break down choline ester drugs efficiently, leading to abnormally prolonged drug effects.  Pseudocholinesterase deficiency can also have nongenetic causes. In these cases, the condition is called acquired pseudocholinesterase deficiency; it is not inherited and cannot be passed to the next generation. Activity of the pseudocholinesterase enzyme can be impaired by kidney or liver disease, malnutrition, major burns, cancer, or certain drugs.
When due to genetic causes, this condition 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 disorder have one copy of the altered gene in each cell and are called carriers. They can pass on the gene mutation to their children, but they do not usually experience signs and symptoms of the disorder. In some cases, carriers of BCHE gene mutations take longer than usual to clear choline ester drugs from the body, but not as long as those with two copies of the altered gene in each cell.
Tourette syndrome is a complex disorder characterized by repetitive, sudden, and involuntary movements or noises called tics. Tics usually appear in childhood, and their severity varies over time. In most cases, tics become milder and less frequent in late adolescence and adulthood.  Tourette syndrome involves both motor tics, which are uncontrolled body movements, and vocal or phonic tics, which are outbursts of sound. Some motor tics are simple and involve only one muscle group. Simple motor tics, such as rapid eye blinking, shoulder shrugging, or nose twitching, are usually the first signs of Tourette syndrome. Motor tics also can be complex (involving multiple muscle groups), such as jumping, kicking, hopping, or spinning.  Vocal tics, which generally appear later than motor tics, also can be simple or complex. Simple vocal tics include grunting, sniffing, and throat-clearing. More complex vocalizations include repeating the words of others (echolalia) or repeating one's own words (palilalia). The involuntary use of inappropriate or obscene language (coprolalia) is possible, but uncommon, among people with Tourette syndrome.  In addition to frequent tics, people with Tourette syndrome are at risk for associated problems including attention deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), anxiety, depression, and problems with sleep.
A variety of genetic and environmental factors likely play a role in causing Tourette syndrome. Most of these factors are unknown, and researchers are studying risk factors before and after birth that may contribute to this complex disorder. Scientists believe that tics may result from changes in brain chemicals (neurotransmitters) that are responsible for producing and controlling voluntary movements.  Mutations involving the SLITRK1 gene have been identified in a small number of people with Tourette syndrome. This gene provides instructions for making a protein that is active in the brain. The SLITRK1 protein probably plays a role in the development of nerve cells, including the growth of specialized extensions (axons and dendrites) that allow each nerve cell to communicate with nearby cells. It is unclear how mutations in the SLITRK1 gene can lead to this disorder.  Most people with Tourette syndrome do not have a mutation in the SLITRK1 gene. Because mutations have been reported in so few people with this condition, the association of the SLITRK1 gene with this disorder has not been confirmed. Researchers suspect that changes in other genes, which have not been identified, are also associated with Tourette syndrome.
The inheritance pattern of Tourette syndrome is unclear. Although the features of this condition can cluster in families, many genetic and environmental factors are likely to be involved. Among family members of an affected person, it is difficult to predict who else may be at risk of developing the condition.  Tourette syndrome was previously thought to have an autosomal dominant pattern of inheritance, which suggests that one mutated copy of a gene in each cell would be sufficient to cause the condition. Several decades of research have shown that this is not the case. Almost all cases of Tourette syndrome probably result from a variety of genetic and environmental factors, not changes in a single gene.
These resources address the diagnosis or management of Tourette syndrome:  - Gene Review: Gene Review: Tourette Disorder Overview  - Genetic Testing Registry: Tourette Syndrome  - MedlinePlus Encyclopedia: Gilles de la Tourette 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
Fibrodysplasia ossificans progressiva (FOP) is a disorder in which muscle tissue and connective tissue such as tendons and ligaments are gradually replaced by bone (ossified), forming bone outside the skeleton (extra-skeletal or heterotopic bone) that constrains movement. This process generally becomes noticeable in early childhood, starting with the neck and shoulders and proceeding down the body and into the limbs.  Extra-skeletal bone formation causes progressive loss of mobility as the joints become affected. Inability to fully open the mouth may cause difficulty in speaking and eating. Over time, people with this disorder may experience malnutrition due to their eating problems. They may also have breathing difficulties as a result of extra bone formation around the rib cage that restricts expansion of the lungs.  Any trauma to the muscles of an individual with fibrodysplasia ossificans progressiva, such as a fall or invasive medical procedures, may trigger episodes of muscle swelling and inflammation (myositis) followed by more rapid ossification in the injured area. Flare-ups may also be caused by viral illnesses such as influenza.  People with fibrodysplasia ossificans progressiva are generally born with malformed big toes. This abnormality of the big toes is a characteristic feature that helps to distinguish this disorder from other bone and muscle problems. Affected individuals may also have short thumbs and other skeletal abnormalities.
Mutations in the ACVR1 gene cause fibrodysplasia ossificans progressiva.  The ACVR1 gene provides instructions for producing a member of a protein family called bone morphogenetic protein (BMP) type I receptors. The ACVR1 protein is found in many tissues of the body including skeletal muscle and cartilage. It helps to control the growth and development of the bones and muscles, including the gradual replacement of cartilage by bone (ossification) that occurs in normal skeletal maturation from birth to young adulthood.  Researchers believe that a mutation in the ACVR1 gene may change the shape of the receptor under certain conditions and disrupt mechanisms that control the receptor's activity. As a result, the receptor may be constantly turned on (constitutive activation). Constitutive activation of the receptor causes overgrowth of bone and cartilage and fusion of joints, resulting in the signs and symptoms of fibrodysplasia ossificans progressiva.
Adenosine monophosphate (AMP) deaminase deficiency is a condition that can affect the muscles used for movement (skeletal muscles). People with this condition do not make enough of an enzyme called AMP deaminase. In most people, AMP deaminase deficiency does not cause any symptoms. People who do experience symptoms typically have muscle pain (myalgia) or weakness after exercise or prolonged physical activity. They often get tired more quickly and stay tired longer than would normally be expected. Some affected individuals have more severe symptoms, but it is unclear whether these symptoms are due solely to a lack of AMP deaminase or additional factors. Muscle weakness is typically apparent beginning in childhood or early adulthood.  Researchers have proposed three types of AMP deaminase deficiency, which are distinguished by their symptoms and genetic cause.
Mutations in the AMPD1 gene cause AMP deaminase deficiency. The AMPD1 gene provides instructions for producing an enzyme called AMP deaminase. This enzyme is found in skeletal muscle, where it plays a role in producing energy within muscle cells. Mutations in the AMPD1 gene disrupt the function of AMP deaminase and impair the muscle cells' ability to produce energy. This lack of energy can lead to myalgia or other muscle problems associated with AMP deaminase deficiency.  The three types of AMP deaminase deficiency are known as the inherited type, acquired type, and coincidental inherited type.  Individuals with the inherited type have a mutation in both copies of the AMPD1 gene in each cell. Most people are asymptomatic, meaning they have no symptoms. Some people with AMP deaminase deficiency experience muscle weakness or pain following exercise.  The acquired type occurs in people who have decreased levels of AMP deaminase due to the presence of a muscle or joint condition.  People with the coincidental inherited type have a mutation in both copies of the AMPD1 gene. Additionally, they have a separate joint or muscle disorder. Some individuals experience more severe joint or muscle symptoms related to their disorder if they have AMP deaminase deficiency than do people without this enzyme deficiency. Most, however, do not have any symptoms associated with AMP deaminase deficiency.  It is not known why most people with this condition do not experience symptoms. Researchers speculate that additional mutations in other genes may be involved.
Snyder-Robinson syndrome is a condition characterized by intellectual disability, muscle and bone abnormalities, and other problems with development. It occurs exclusively in males.  Males with Snyder-Robinson syndrome have delayed development and intellectual disability beginning in early childhood. The intellectual disability can range from mild to profound. Speech often develops late, and speech difficulties are common. Some affected individuals never develop any speech.  Most affected males are thin and have low muscle mass, a body type described as an asthenic habitus. Weakness or "floppiness" (hypotonia) typically becomes apparent in infancy, and the loss of muscle tissue continues with age. People with this condition often have difficulty walking; most have an unsteady gait.  Snyder-Robinson syndrome causes skeletal problems, particularly thinning of the bones (osteoporosis) that starts in early childhood. Osteoporosis causes the bones to be brittle and to break easily, often during normal activities. In people with Snyder-Robinson syndrome, broken bones occur most often in the arms and legs. Most affected individuals also develop an abnormal side-to-side and back-to-front curvature of the spine (scoliosis and kyphosis, often called kyphoscoliosis when they occur together). Affected individuals tend to be shorter than their peers and others in their family.  Snyder-Robinson syndrome is associated with distinctive facial features, including a prominent lower lip; a high, narrow roof of the mouth or an opening in the roof of the mouth (a cleft palate); and differences in the size and shape of the right and left sides of the face (facial asymmetry). Other signs and symptoms that have been reported include seizures that begin in childhood and abnormalities of the genitalia and kidneys.
Snyder-Robinson syndrome results from mutations in the SMS gene. This gene provides instructions for making an enzyme called spermine synthase. This enzyme is involved in the production of spermine, which is a type of small molecule called a polyamine. Polyamines have many critical functions within cells. Studies suggest that these molecules play roles in cell growth and division, the production of new proteins, the repair of damaged tissues, the function of molecules called ion channels, and the controlled self-destruction of cells (apoptosis). Polyamines appear to be necessary for normal development and function of the brain and other parts of the body.  Mutations in the SMS gene greatly reduce or eliminate the activity of spermine synthase, which decreases the amount of spermine in cells. A shortage of this polyamine clearly impacts normal development, including the development of the brain, muscles, and bones, but it is unknown how it leads to the specific signs and symptoms of Snyder-Robinson syndrome.
This condition is inherited in an X-linked recessive pattern. The gene associated with this condition 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. No cases of Snyder-Robinson syndrome in females have been reported.
Thrombotic thrombocytopenic purpura is a rare disorder that causes blood clots (thrombi) to form in small blood vessels throughout the body. These clots can cause serious medical problems if they block vessels and restrict blood flow to organs such as the brain, kidneys, and heart. Resulting complications can include neurological problems (such as personality changes, headaches, confusion, and slurred speech), fever, abnormal kidney function, abdominal pain, and heart problems.  Blood clots normally form to prevent excess blood loss at the site of an injury. In people with thrombotic thrombocytopenic purpura, clots develop in blood vessels even in the absence of injury. Blood clots are formed from clumps of cell fragments called platelets, which circulate in the blood and assist with clotting. Because a large number of platelets are used to make clots in people with thrombotic thrombocytopenic purpura, fewer platelets are available in the bloodstream. A reduced level of circulating platelets is known as thrombocytopenia. Thrombocytopenia can lead to small areas of bleeding just under the surface of the skin, resulting in purplish spots called purpura.  This disorder also causes red blood cells to break down (undergo hemolysis) prematurely. As blood squeezes past clots within blood vessels, red blood cells can break apart. A condition called hemolytic anemia occurs when red blood cells are destroyed faster than the body can replace them. This type of anemia leads to paleness, yellowing of the eyes and skin (jaundice), fatigue, shortness of breath, and a rapid heart rate.  There are two major forms of thrombotic thrombocytopenic purpura, an acquired (noninherited) form and a familial form. The acquired form usually appears in late childhood or adulthood. Affected individuals may have a single episode of signs and symptoms, or they may recur over time. The familial form of this disorder is much rarer and typically appears in infancy or early childhood. In people with the familial form, signs and symptoms often recur on a regular basis.
Mutations in the ADAMTS13 gene cause the familial form of thrombotic thrombocytopenic purpura. The ADAMTS13 gene provides instructions for making an enzyme that is involved in the normal process of blood clotting. Mutations in this gene lead to a severe reduction in the activity of this enzyme. The acquired form of thrombotic thrombocytopenic purpura also results from a reduction in ADAMTS13 enzyme activity; however, people with the acquired form do not have mutations in the ADAMTS13 gene. Instead, their immune systems often produce specific proteins called autoantibodies that block the activity of the enzyme.  A lack of ADAMTS13 enzyme activity disrupts the usual balance between bleeding and clotting. Normally, blood clots form at the site of an injury to seal off damaged blood vessels and prevent excess blood loss. In people with thrombotic thrombocytopenic purpura, clots form throughout the body as platelets bind together abnormally and stick to the walls of blood vessels. These clots can block small blood vessels, causing organ damage and the other features of thrombotic thrombocytopenic purpura.  Researchers believe that other genetic or environmental factors may contribute to the signs and symptoms of thrombotic thrombocytopenic purpura. In people with reduced ADAMTS13 enzyme activity, factors such as pregnancy, surgery, and infection may trigger abnormal blood clotting and its associated complications.
These resources address the diagnosis or management of thrombotic thrombocytopenic purpura:  - Genetic Testing Registry: Upshaw-Schulman syndrome  - MedlinePlus Encyclopedia: Blood Clots  - MedlinePlus Encyclopedia: Hemolytic anemia  - MedlinePlus Encyclopedia: Purpura  - MedlinePlus Encyclopedia: Thrombocytopenia  - MedlinePlus Encyclopedia: Thrombotic thrombocytopenic purpura   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
Autosomal dominant hypocalcemia is characterized by low levels of calcium in the blood (hypocalcemia). Affected individuals can have an imbalance of other molecules in the blood as well, including too much phosphate (hyperphosphatemia) or too little magnesium (hypomagnesemia). Some people with autosomal dominant hypocalcemia also have low levels of a hormone called parathyroid hormone (hypoparathyroidism). This hormone is involved in the regulation of calcium levels in the blood. Abnormal levels of calcium and other molecules in the body can lead to a variety of signs and symptoms, although about half of affected individuals have no associated health problems.  The most common features of autosomal dominant hypocalcemia include muscle spasms in the hands and feet (carpopedal spasms) and muscle cramping, prickling or tingling sensations (paresthesias), or twitching of the nerves and muscles (neuromuscular irritability) in various parts of the body. More severely affected individuals develop seizures, usually in infancy or childhood. Sometimes, these symptoms occur only during episodes of illness or fever.  Some people with autosomal dominant hypocalcemia have high levels of calcium in their urine (hypercalciuria), which can lead to deposits of calcium in the kidneys (nephrocalcinosis) or the formation of kidney stones (nephrolithiasis). These conditions can damage the kidneys and impair their function. Sometimes, abnormal deposits of calcium form in the brain, typically in structures called basal ganglia, which help control movement.  A small percentage of severely affected individuals have features of a kidney disorder called Bartter syndrome in addition to hypocalcemia. These features can include a shortage of potassium (hypokalemia) and magnesium and a buildup of the hormone aldosterone (hyperaldosteronism) in the blood. The abnormal balance of molecules can raise the pH of the blood, which is known as metabolic alkalosis. The combination of features of these two conditions is sometimes referred to as autosomal dominant hypocalcemia with Bartter syndrome or Bartter syndrome type V.  There are two types of autosomal dominant hypocalcemia distinguished by their genetic cause. The signs and symptoms of the two types are generally the same.
Autosomal dominant hypocalcemia is primarily caused by mutations in the CASR gene; these cases are known as type 1. A small percentage of cases, known as type 2, are caused by mutations in the GNA11 gene. The proteins produced from these genes work together to regulate the amount of calcium in the blood.  The CASR gene provides instructions for making a protein called the calcium-sensing receptor (CaSR). Calcium molecules attach (bind) to the CaSR protein, which allows this protein to monitor and regulate the amount of calcium in the blood. G11, which is produced from the GNA11 gene, is one component of a signaling protein that works in conjunction with CaSR. When a certain concentration of calcium is reached, CaSR stimulates G11 to send signals to block processes that increase the amount of calcium in the blood.  Mutations in the CASR or GNA11 gene lead to overactivity of the respective protein. The altered CaSR protein is more sensitive to calcium, meaning even low levels of calcium can trigger it to stimulate G11 signaling. Similarly, the altered G11 protein continues to send signals to prevent calcium increases, even when levels in the blood are very low. As a result, calcium levels in the blood remain low, causing hypocalcemia. Calcium plays an important role in the control of muscle movement, and a shortage of this molecule can lead to cramping or twitching of the muscles. Impairment of the processes that increase calcium can also disrupt the normal regulation of other molecules, such as phosphate and magnesium, leading to other signs of autosomal dominant hypocalcemia. Studies show that the lower the amount of calcium in the blood, the more severe the symptoms of the condition are.
Progressive supranuclear palsy is a brain disorder that affects movement, vision, speech, and thinking ability (cognition). The signs and symptoms of this disorder usually become apparent in mid- to late adulthood, most often in a person's 60s. Most people with progressive supranuclear palsy survive 5 to 9 years after the disease first appears, although a few affected individuals have lived for more than a decade.  Loss of balance and frequent falls are the most common early signs of progressive supranuclear palsy. Affected individuals have problems with walking, including poor coordination and an unsteady, lurching gait. Other movement abnormalities develop as the disease progresses, including unusually slow movements (bradykinesia), clumsiness, and stiffness of the trunk muscles. These problems worsen with time, and most affected people ultimately require wheelchair assistance.  Progressive supranuclear palsy is also characterized by abnormal eye movements, which typically develop several years after the other movement problems first appear. Restricted up-and-down eye movement (vertical gaze palsy) is a hallmark of this disease. Other eye movement problems include difficulty opening and closing the eyelids, infrequent blinking, and pulling back (retraction) of the eyelids. These abnormalities can lead to blurred vision, an increased sensitivity to light (photophobia), and a staring gaze.  Additional features of progressive supranuclear palsy include slow and slurred speech (dysarthria) and trouble swallowing (dysphagia). Most affected individuals also experience changes in personality and behavior, such as a general loss of interest and enthusiasm (apathy). They develop problems with cognition, including difficulties with attention, planning, and problem solving. As the cognitive and behavioral problems worsen, affected individuals increasingly require help with personal care and other activities of daily living.