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What is (are) sickle cell disease ? | Sickle cell disease is a group of disorders that affects hemoglobin, the molecule in red blood cells that delivers oxygen to cells throughout the body. People with this disorder have atypical hemoglobin molecules called hemoglobin S, which can distort red blood cells into a sickle, or crescent, shape. Signs and symptoms of sickle cell disease usually begin in early childhood. Characteristic features of this disorder include a low number of red blood cells (anemia), repeated infections, and periodic episodes of pain. The severity of symptoms varies from person to person. Some people have mild symptoms, while others are frequently hospitalized for more serious complications. The signs and symptoms of sickle cell disease are caused by the sickling of red blood cells. When red blood cells sickle, they break down prematurely, which can lead to anemia. Anemia can cause shortness of breath, fatigue, and delayed growth and development in children. The rapid breakdown of red blood cells may also cause yellowing of the eyes and skin, which are signs of jaundice. Painful episodes can occur when sickled red blood cells, which are stiff and inflexible, get stuck in small blood vessels. These episodes deprive tissues and organs of oxygen-rich blood and can lead to organ damage, especially in the lungs, kidneys, spleen, and brain. A particularly serious complication of sickle cell disease is high blood pressure in the blood vessels that supply the lungs (pulmonary hypertension). Pulmonary hypertension occurs in about one-third of adults with sickle cell disease and can lead to heart failure. | sickle cell disease |
How many people are affected by sickle cell disease ? | Sickle cell disease affects millions of people worldwide. It is most common among people whose ancestors come from Africa; Mediterranean countries such as Greece, Turkey, and Italy; the Arabian Peninsula; India; and Spanish-speaking regions in South America, Central America, and parts of the Caribbean. Sickle cell disease is the most common inherited blood disorder in the United States, affecting 70,000 to 80,000 Americans. The disease is estimated to occur in 1 in 500 African Americans and 1 in 1,000 to 1,400 Hispanic Americans. | sickle cell disease |
What are the genetic changes related to sickle cell disease ? | Mutations in the HBB gene cause sickle cell disease. Hemoglobin consists of four protein subunits, typically, two subunits called alpha-globin and two subunits called beta-globin. The HBB gene provides instructions for making beta-globin. Various versions of beta-globin result from different mutations in the HBB gene. One particular HBB gene mutation produces an abnormal version of beta-globin known as hemoglobin S (HbS). Other mutations in the HBB gene lead to additional abnormal versions of beta-globin such as hemoglobin C (HbC) and hemoglobin E (HbE). HBB gene mutations can also result in an unusually low level of beta-globin; this abnormality is called beta thalassemia. In people with sickle cell disease, at least one of the beta-globin subunits in hemoglobin is replaced with hemoglobin S. In sickle cell anemia, which is a common form of sickle cell disease, hemoglobin S replaces both beta-globin subunits in hemoglobin. In other types of sickle cell disease, just one beta-globin subunit in hemoglobin is replaced with hemoglobin S. The other beta-globin subunit is replaced with a different abnormal variant, such as hemoglobin C. For example, people with sickle-hemoglobin C (HbSC) disease have hemoglobin molecules with hemoglobin S and hemoglobin C instead of beta-globin. If mutations that produce hemoglobin S and beta thalassemia occur together, individuals have hemoglobin S-beta thalassemia (HbSBetaThal) disease. Abnormal versions of beta-globin can distort red blood cells into a sickle shape. The sickle-shaped red blood cells die prematurely, which can lead to anemia. Sometimes the inflexible, sickle-shaped cells get stuck in small blood vessels and can cause serious medical complications. | sickle cell disease |
Is sickle cell disease inherited ? | 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. | sickle cell disease |
What are the treatments for sickle cell disease ? | These resources address the diagnosis or management of sickle cell disease: - Baby's First Test: S, Beta-Thalassemia - Baby's First Test: S, C Disease - Baby's First Test: Sickle Cell Anemia - Gene Review: Gene Review: Sickle Cell Disease - Genetic Testing Registry: Hb SS disease - Genomics Education Programme (UK) - Howard University Hospital Center for Sickle Cell Disease - MedlinePlus Encyclopedia: Sickle Cell Anemia - MedlinePlus Encyclopedia: Sickle Cell Test 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 | sickle cell disease |
What is (are) beta-mannosidosis ? | Beta-mannosidosis is a rare inherited disorder affecting the way certain sugar molecules are processed in the body. Signs and symptoms of beta-mannosidosis vary widely in severity, and the age of onset ranges between infancy and adolescence. Almost all individuals with beta-mannosidosis experience intellectual disability, and some have delayed motor development and seizures. Affected individuals may be extremely introverted, prone to depression, or have behavioral problems such as hyperactivity, impulsivity or aggression. People with beta-mannosidosis may experience an increased risk of respiratory and ear infections, hearing loss, speech impairment, swallowing difficulties, poor muscle tone (hypotonia), and reduced sensation or other nervous system abnormalities in the extremities (peripheral neuropathy). They may also exhibit distinctive facial features and clusters of enlarged blood vessels forming small, dark red spots on the skin (angiokeratomas). | beta-mannosidosis |
How many people are affected by beta-mannosidosis ? | Beta-mannosidosis is believed to be a very rare disorder. Approximately 20 affected individuals have been reported worldwide. It is difficult to determine the specific incidence of beta-mannosidosis, because people with mild or non-specific symptoms may never be diagnosed. | beta-mannosidosis |
What are the genetic changes related to beta-mannosidosis ? | Mutations in the MANBA gene cause beta-mannosidosis. The MANBA gene provides instructions for making the enzyme beta-mannosidase. This enzyme works in the lysosomes, which are compartments that digest and recycle materials in the cell. Within lysosomes, the enzyme helps break down complexes of sugar molecules (oligosaccharides) attached to certain proteins (glycoproteins). Beta-mannosidase is involved in the last step of this process, helping to break down complexes of two sugar molecules (disaccharides) containing a sugar molecule called mannose. Mutations in the MANBA gene interfere with the ability of the beta-mannosidase enzyme to perform its role in breaking down mannose-containing disaccharides. These disaccharides gradually accumulate in the lysosomes and cause cells to malfunction, resulting in the signs and symptoms of beta-mannosidosis. | beta-mannosidosis |
Is beta-mannosidosis inherited ? | 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. | beta-mannosidosis |
What are the treatments for beta-mannosidosis ? | These resources address the diagnosis or management of beta-mannosidosis: - Genetic Testing Registry: Beta-D-mannosidosis 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 | beta-mannosidosis |
What is (are) hyperphosphatemic familial tumoral calcinosis ? | Hyperphosphatemic familial tumoral calcinosis (HFTC) is a condition characterized by an increase in the levels of phosphate in the blood (hyperphosphatemia) and abnormal deposits of phosphate and calcium (calcinosis) in the body's tissues. Calcinosis typically develops in early childhood to early adulthood, although in some people the deposits first appear in infancy or in late adulthood. Calcinosis usually occurs in and just under skin tissue around the joints, most often the hips, shoulders, and elbows. Calcinosis may also develop in the soft tissue of the feet, legs, and hands. Rarely, calcinosis occurs in blood vessels or in the brain and can cause serious health problems. The deposits develop over time and vary in size. Larger deposits form masses that are noticeable under the skin and can interfere with the function of joints and impair movement. These large deposits may appear tumor-like (tumoral), but they are not tumors or cancerous. The number and frequency of deposits varies among affected individuals; some develop few deposits during their lifetime, while others may develop many in a short period of time. Other features of HFTC include eye abnormalities such as calcium buildup in the clear front covering of the eye (corneal calcification) or angioid streaks that occur when tiny breaks form in the layer of tissue at the back of the eye called Bruch's membrane. Inflammation of the long bones (diaphysis) or excessive bone growth (hyperostosis) may occur. Some affected individuals have dental abnormalities. In males, small crystals of cholesterol can accumulate (microlithiasis) in the testicles, which usually causes no health problems. A similar condition called hyperphosphatemia-hyperostosis syndrome (HHS) results in increased levels of phosphate in the blood, excessive bone growth, and bone lesions. This condition used to be considered a separate disorder, but it is now thought to be a mild variant of HFTC. | hyperphosphatemic familial tumoral calcinosis |
How many people are affected by hyperphosphatemic familial tumoral calcinosis ? | The prevalence of HFTC is unknown, but it is thought to be a rare condition. It occurs most often in Middle Eastern and African populations. | hyperphosphatemic familial tumoral calcinosis |
What are the genetic changes related to hyperphosphatemic familial tumoral calcinosis ? | Mutations in the FGF23, GALNT3, or KL gene cause HFTC. The proteins produced from these genes are all involved in the regulation of phosphate levels within the body (phosphate homeostasis). Among its many functions, phosphate plays a critical role in the formation and growth of bones in childhood and helps maintain bone strength in adults. Phosphate levels are controlled in large part by the kidneys. The kidneys normally rid the body of excess phosphate by excreting it in urine, and they reabsorb this mineral into the bloodstream when more is needed. The FGF23 gene provides instructions for making a protein called fibroblast growth factor 23, which is produced in bone cells and signals the kidneys to stop reabsorbing phosphate. The proteins produced from the GALNT3 and KL genes help to regulate fibroblast growth factor 23. The protein produced from the GALNT3 gene, called ppGalNacT3, attaches sugar molecules to fibroblast growth factor 23 in a process called glycosylation. Glycosylation allows fibroblast growth factor 23 to move out of the cell and protects the protein from being broken down. Once outside the bone cell, fibroblast growth factor 23 must attach (bind) to a receptor protein that spans the membrane of kidney cells. The protein produced from the KL gene, called alpha-klotho, turns on (activates) the receptor protein so that fibroblast growth factor 23 can bind to it. Binding of fibroblast growth factor 23 to its receptor stimulates signaling that stops phosphate reabsorption into the bloodstream. Mutations in the FGF23, GALNT3, or KL gene lead to a disruption in fibroblast growth factor 23 signaling. FGF23 gene mutations result in the production of a protein with decreased function that quickly gets broken down. Mutations in the GALNT3 gene result in the production of ppGalNacT3 protein with little or no function. As a result, the protein cannot glycosylate fibroblast growth factor 23, which is consequently trapped inside the cell and broken down rather than being released from the cell (secreted). KL gene mutations lead to a shortage of functional alpha-klotho. As a result, the receptor protein is not activated, causing it to be unavailable to be bound to fibroblast growth factor 23. All of these impairments to fibroblast growth factor 23 function and signaling lead to increased phosphate absorption by the kidneys. Calcinosis results when the excess phosphate combines with calcium to form deposits that build up in soft tissues. Although phosphate levels are increased, calcium is typically within the normal range. | hyperphosphatemic familial tumoral calcinosis |
Is hyperphosphatemic familial tumoral calcinosis inherited ? | 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. | hyperphosphatemic familial tumoral calcinosis |
What are the treatments for hyperphosphatemic familial tumoral calcinosis ? | These resources address the diagnosis or management of hyperphosphatemic familial tumoral calcinosis: - Genetic Testing Registry: Tumoral calcinosis, familial, hyperphosphatemic 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 | hyperphosphatemic familial tumoral calcinosis |
What is (are) pulmonary alveolar microlithiasis ? | Pulmonary alveolar microlithiasis is a disorder in which many tiny fragments (microliths) of a compound called calcium phosphate gradually accumulate in the small air sacs (alveoli) located throughout the lungs. These deposits eventually cause widespread damage to the alveoli and surrounding lung tissue (interstitial lung disease) that leads to breathing problems. People with this disorder can develop a persistent cough and difficulty breathing (dyspnea), especially during physical exertion. Affected individuals may also experience chest pain that worsens when coughing, sneezing, or taking deep breaths. Pulmonary alveolar microlithiasis is usually diagnosed before age 40. Often the disorder is discovered before symptoms develop, when medical imaging is done for other reasons. The condition typically worsens slowly over many years, although some affected individuals have signs and symptoms that remain stable for long periods of time. People with pulmonary alveolar microlithiasis can also develop calcium phosphate deposits in other organs and tissues of the body, including the kidneys, gallbladder, testes, and the valve that connects a large blood vessel called the aorta with the heart (the aortic valve). In rare cases, affected individuals have complications related to accumulation of these deposits, such as a narrowing (stenosis) of the aortic valve that can impede normal blood flow. | pulmonary alveolar microlithiasis |
How many people are affected by pulmonary alveolar microlithiasis ? | Pulmonary alveolar microlithiasis is a rare disorder; its prevalence is unknown. About 600 affected individuals have been described in the medical literature, of whom about a quarter are of Turkish descent. The remainder come from populations worldwide. | pulmonary alveolar microlithiasis |
What are the genetic changes related to pulmonary alveolar microlithiasis ? | Pulmonary alveolar microlithiasis is caused by mutations in the SLC34A2 gene. This gene provides instructions for making a protein called the type IIb sodium-phosphate cotransporter, which plays a role in the regulation of phosphate levels (phosphate homeostasis). Although this protein can be found in several organs and tissues in the body, it is located mainly in the lungs, specifically in cells in the alveoli called alveolar type II cells. These cells produce and recycle surfactant, which is a mixture of certain phosphate-containing fats (called phospholipids) and proteins that lines the lung tissue and makes breathing easy. The recycling of surfactant releases phosphate into the alveoli. Research suggests that the type IIb sodium-phosphate cotransporter normally helps clear this phosphate. SLC34A2 gene mutations are thought to impair the activity of the type IIb sodium-phosphate cotransporter, resulting in the accumulation of phosphate in the alveoli. The accumulated phosphate forms the microliths that cause the signs and symptoms of pulmonary alveolar microlithiasis. | pulmonary alveolar microlithiasis |
Is pulmonary alveolar microlithiasis inherited ? | 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. | pulmonary alveolar microlithiasis |
What are the treatments for pulmonary alveolar microlithiasis ? | These resources address the diagnosis or management of pulmonary alveolar microlithiasis: - Genetic Testing Registry: Pulmonary alveolar microlithiasis - MedlinePlus Health Topic: Oxygen Therapy - MedlinePlus Health Topic: Pulmonary Rehabilitation - National Jewish Health: Interstitial Lung Disease - Rare Diseases Clinical Research Network: Rare Lung Disease Consortium 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 | pulmonary alveolar microlithiasis |
What is (are) Caffey disease ? | Caffey disease, also called infantile cortical hyperostosis, is a bone disorder that most often occurs in babies. Excessive new bone formation (hyperostosis) is characteristic of Caffey disease. The bone abnormalities mainly affect the jawbone, shoulder blades (scapulae), collarbones (clavicles), and the shafts (diaphyses) of long bones in the arms and legs. Affected bones may double or triple in width, which can be seen by x-ray imaging. In some cases two bones that are next to each other, such as two ribs or the pairs of long bones in the forearms (radius and ulna) or lower legs (tibia and fibula) become fused together. Babies with Caffey disease also have swelling of joints and of soft tissues such as muscles, with pain and redness in the affected areas. Affected infants can also be feverish and irritable. The signs and symptoms of Caffey disease are usually apparent by the time an infant is 5 months old. In rare cases, skeletal abnormalities can be detected by ultrasound imaging during the last few weeks of development before birth. Lethal prenatal cortical hyperostosis, a more severe disorder that appears earlier in development and is often fatal before or shortly after birth, is sometimes called lethal prenatal Caffey disease; however, it is generally considered to be a separate disorder. For unknown reasons, the swelling and pain associated with Caffey disease typically go away within a few months. Through a normal process called bone remodeling, which replaces old bone tissue with new bone, the excess bone is usually reabsorbed by the body and undetectable on x-ray images by the age of 2. However, if two adjacent bones have fused, they may remain that way, possibly resulting in complications. For example, fused rib bones can lead to curvature of the spine (scoliosis) or limit expansion of the chest, resulting in breathing problems. Most people with Caffey disease have no further problems related to the disorder after early childhood. Occasionally, another episode of hyperostosis occurs years later. In addition, some adults who had Caffey disease in infancy have other abnormalities of the bones and connective tissues, which provide strength and flexibility to structures throughout the body. Affected adults may have loose joints (joint laxity), stretchy (hyperextensible) skin, or be prone to protrusion of organs through gaps in muscles (hernias). | Caffey disease |
How many people are affected by Caffey disease ? | Caffey disease has been estimated to occur in approximately 3 per 1,000 infants worldwide. A few hundred cases have been described in the medical literature. Researchers believe this condition is probably underdiagnosed because it usually goes away by itself in early childhood. | Caffey disease |
What are the genetic changes related to Caffey disease ? | A mutation in the COL1A1 gene causes Caffey disease. The COL1A1 gene provides instructions for making part of a large molecule called type I collagen. Collagens are a family of proteins that strengthen and support many tissues in the body, including cartilage, bone, tendon, and skin. In these tissues, type I collagen is found in the spaces around cells. The collagen molecules are cross-linked in long, thin, fibrils that are very strong and flexible. Type I collagen is the most abundant form of collagen in the human body. The COL1A1 gene mutation that causes Caffey disease replaces the protein building block (amino acid) arginine with the amino acid cysteine at protein position 836 (written as Arg836Cys or R836C). This mutation results in the production of type I collagen fibrils that are variable in size and shape, but it is unknown how these changes lead to the signs and symptoms of Caffey disease. | Caffey disease |
Is Caffey disease inherited ? | This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is usually sufficient to cause the disorder. About 20 percent of people who have the mutation that causes Caffey disease do not experience its signs or symptoms; this phenomenon is called incomplete penetrance. In some cases, an affected person inherits the mutation that causes Caffey disease from a parent. Other cases result from new mutations in the gene and occur in people with no history of the disorder in their family. | Caffey disease |
What are the treatments for Caffey disease ? | These resources address the diagnosis or management of Caffey disease: - Cedars-Sinai: Skeletal Dysplasia - Gene Review: Gene Review: Caffey Disease - Genetic Testing Registry: Infantile cortical hyperostosis 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 | Caffey disease |
What is (are) acatalasemia ? | Acatalasemia is a condition characterized by very low levels of an enzyme called catalase. Many people with acatalasemia never have any health problems related to the condition and are diagnosed because they have affected family members. Some of the first reported individuals with acatalasemia developed open sores (ulcers) inside the mouth that led to the death of soft tissue (gangrene). When mouth ulcers and gangrene occur with acatalasemia, the condition is known as Takahara disease. These complications are rarely seen in more recent cases of acatalasemia, probably because of improvements in oral hygiene. Studies suggest that people with acatalasemia have an increased risk of developing type 2 diabetes mellitus, which is the most common form of diabetes. A higher percentage of people with acatalasemia have type 2 diabetes mellitus than in the general population, and the disease tends to develop at an earlier age (in a person's thirties or forties, on average). Researchers speculate that acatalasemia could also be a risk factor for other common, complex diseases; however, only a small number of cases have been studied. | acatalasemia |
How many people are affected by acatalasemia ? | More than 100 cases of acatalasemia have been reported in the medical literature. Researchers estimate that the condition occurs in about 1 in 12,500 people in Japan, 1 in 20,000 people in Hungary, and 1 in 25,000 people in Switzerland. The prevalence of acatalasemia in other populations is unknown. | acatalasemia |
What are the genetic changes related to acatalasemia ? | Mutations in the CAT gene can cause acatalasemia. This gene provides instructions for making the enzyme catalase, which breaks down hydrogen peroxide molecules into oxygen and water. Hydrogen peroxide is produced through chemical reactions within cells. At low levels, it is involved in several chemical signaling pathways, but at high levels it is toxic to cells. If hydrogen peroxide is not broken down by catalase, additional reactions convert it into compounds called reactive oxygen species that can damage DNA, proteins, and cell membranes. Mutations in the CAT gene greatly reduce the activity of catalase. A shortage of this enzyme can allow hydrogen peroxide to build up to toxic levels in certain cells. For example, hydrogen peroxide produced by bacteria in the mouth may accumulate in and damage soft tissues, leading to mouth ulcers and gangrene. A buildup of hydrogen peroxide may also damage beta cells of the pancreas, which release a hormone called insulin that helps control blood sugar. Malfunctioning beta cells are thought to underlie the increased risk of type 2 diabetes mellitus in people with acatalasemia. It is unclear why some people have no health problems associated with a loss of catalase activity. Many people with reduced catalase activity do not have an identified mutation in the CAT gene; in these cases, the cause of the condition is unknown. Researchers believe that other genetic and environmental factors can also influence the activity of catalase. | acatalasemia |
Is acatalasemia inherited ? | Acatalasemia has an autosomal recessive pattern of inheritance, which means both copies of the CAT gene in each cell have mutations. When both copies of the gene are altered, the activity of catalase is reduced to less than 10 percent of normal. When only one of the two copies of the CAT gene has a mutation, the activity of catalase is reduced by approximately half. This reduction in catalase activity is often called hypocatalasemia. Like acatalasemia, hypocatalasemia usually does not cause any health problems. | acatalasemia |
What are the treatments for acatalasemia ? | These resources address the diagnosis or management of acatalasemia: - Genetic Testing Registry: Acatalasemia - Genetic Testing Registry: Acatalasemia, japanese type 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 | acatalasemia |
What is (are) ankyloblepharon-ectodermal defects-cleft lip/palate syndrome ? | Ankyloblepharon-ectodermal defects-cleft lip/palate (AEC) syndrome is a form 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. Among the most common features of AEC syndrome are missing patches of skin (erosions). In affected infants, skin erosions most commonly occur on the scalp. They tend to recur throughout childhood and into adulthood, frequently affecting the scalp, neck, hands, and feet. The skin erosions range from mild to severe and can lead to infection, scarring, and hair loss. Other ectodermal abnormalities in AEC syndrome include changes in skin coloring; brittle, sparse, or missing hair; misshapen or absent fingernails and toenails; and malformed or missing teeth. Affected individuals also report increased sensitivity to heat and a reduced ability to sweat. Many infants with AEC syndrome are born with an eyelid condition known as ankyloblepharon filiforme adnatum, in which strands of tissue partially or completely fuse the upper and lower eyelids. Most people with AEC syndrome are also born with an opening in the roof of the mouth (a cleft palate), a split in the lip (a cleft lip), or both. Cleft lip or cleft palate can make it difficult for affected infants to suck, so these infants often have trouble feeding and do not grow and gain weight at the expected rate (failure to thrive). Additional features of AEC syndrome can include limb abnormalities, most commonly fused fingers and toes (syndactyly). Less often, affected individuals have permanently bent fingers and toes (camptodactyly) or a deep split in the hands or feet with missing fingers or toes and fusion of the remaining digits (ectrodactyly). Hearing loss is common, occurring in more than 90 percent of children with AEC syndrome. Some affected individuals have distinctive facial features, such as small jaws that cannot open fully and a narrow space between the upper lip and nose (philtrum). Other signs and symptoms can include the opening of the urethra on the underside of the penis (hypospadias) in affected males, digestive problems, absent tear duct openings in the eyes, and chronic sinus or ear infections. A condition known as Rapp-Hodgkin syndrome has signs and symptoms that overlap considerably with those of AEC syndrome. These two syndromes were classified as separate disorders until it was discovered that they both result from mutations in the same part of the same gene. Most researchers now consider Rapp-Hodgkin syndrome and AEC syndrome to be part of the same disease spectrum. | ankyloblepharon-ectodermal defects-cleft lip/palate syndrome |
How many people are affected by ankyloblepharon-ectodermal defects-cleft lip/palate syndrome ? | AEC syndrome is a rare condition; its prevalence is unknown. All forms of ectodermal dysplasia together occur in about 1 in 100,000 newborns in the United States. | ankyloblepharon-ectodermal defects-cleft lip/palate syndrome |
What are the genetic changes related to ankyloblepharon-ectodermal defects-cleft lip/palate syndrome ? | AEC syndrome is caused by mutations in the TP63 gene. This gene provides instructions for making a protein known as p63, which plays an essential role in early development. The p63 protein is a transcription factor, which means that it attaches (binds) to DNA and controls the activity of particular genes. The p63 protein turns many different genes on and off during development. It appears to be especially critical for the development of ectodermal structures, such as the skin, hair, teeth, and nails. Studies suggest that it also plays important roles in the development of the limbs, facial features, urinary system, and other organs and tissues. The TP63 gene mutations responsible for AEC syndrome interfere with the ability of p63 to turn target genes on and off at the right times. It is unclear how these changes lead to abnormal ectodermal development and the specific features of AEC syndrome. | ankyloblepharon-ectodermal defects-cleft lip/palate syndrome |
Is ankyloblepharon-ectodermal defects-cleft lip/palate syndrome inherited ? | 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. | ankyloblepharon-ectodermal defects-cleft lip/palate syndrome |
What are the treatments for ankyloblepharon-ectodermal defects-cleft lip/palate syndrome ? | These resources address the diagnosis or management of AEC syndrome: - Gene Review: Gene Review: TP63-Related Disorders - Genetic Testing Registry: Hay-Wells syndrome of ectodermal dysplasia - Genetic Testing Registry: Rapp-Hodgkin ectodermal dysplasia 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 | ankyloblepharon-ectodermal defects-cleft lip/palate syndrome |
What is (are) Blau syndrome ? | Blau syndrome is an inflammatory disorder that primarily affects the skin, joints, and eyes. Signs and symptoms begin in childhood, usually before age 4. A form of skin inflammation called granulomatous dermatitis is typically the earliest sign of Blau syndrome. This skin condition causes a persistent rash that can be scaly or involve hard lumps (nodules) that can be felt under the skin. The rash is usually found on the torso, arms, and legs. Arthritis is another common feature of Blau syndrome. In affected individuals, arthritis is characterized by inflammation of the lining of joints (the synovium). This inflammation, known as synovitis, is associated with swelling and joint pain. Synovitis usually begins in the joints of the hands, feet, wrists, and ankles. As the condition worsens, it can restrict movement by decreasing the range of motion in many joints. Most people with Blau syndrome also develop uveitis, which is swelling and inflammation of the middle layer of the eye (the uvea). The uvea includes the colored portion of the eye (the iris) and related tissues that underlie the white part of the eye (the sclera). Uveitis can cause eye irritation and pain, increased sensitivity to bright light (photophobia), and blurred vision. Other structures in the eye can also become inflamed, including the outermost protective layer of the eye (the conjunctiva), the tear glands, the specialized light-sensitive tissue that lines the back of the eye (the retina), and the nerve that carries information from the eye to the brain (the optic nerve). Inflammation of any of these structures can lead to severe vision impairment or blindness. Less commonly, Blau syndrome can affect other parts of the body, including the liver, kidneys, brain, blood vessels, lungs, and heart. Inflammation involving these organs and tissues can cause life-threatening complications. | Blau syndrome |
How many people are affected by Blau syndrome ? | Although Blau syndrome appears to be uncommon, its prevalence is unknown. | Blau syndrome |
What are the genetic changes related to Blau syndrome ? | Blau syndrome results from mutations in the NOD2 gene. The protein produced from this gene helps defend the body from foreign invaders, such as viruses and bacteria, by playing several essential roles in the immune response, including inflammatory reactions. An inflammatory reaction occurs when the immune system sends signaling molecules and white blood cells to a site of injury or disease to fight microbial invaders and facilitate tissue repair. The NOD2 gene mutations that cause Blau syndrome result in a NOD2 protein that is overactive, which can trigger an abnormal inflammatory reaction. However, it is unclear how overactivation of the NOD2 protein causes the specific pattern of inflammation affecting the joints, eyes, and skin that is characteristic of Blau syndrome. | Blau syndrome |
Is Blau syndrome inherited ? | Blau syndrome is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. Most affected individuals have one parent with the condition. In some cases, people with the characteristic features of Blau syndrome do not have a family history of the condition. Some researchers believe that these individuals have a non-inherited version of the disorder called early-onset sarcoidosis. | Blau syndrome |
What are the treatments for Blau syndrome ? | These resources address the diagnosis or management of Blau syndrome: - Genetic Testing Registry: Blau syndrome - Genetic Testing Registry: Sarcoidosis, early-onset - Merck Manual Consumer Version: Overview of Dermatitis - Merck Manual Consumer Version: Uveitis 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 | Blau syndrome |
What is (are) Pallister-Hall syndrome ? | Pallister-Hall syndrome is a disorder that affects the development of many parts of the body. Most people with this condition have extra fingers and/or toes (polydactyly), and the skin between some fingers or toes may be fused (cutaneous syndactyly). An abnormal growth in the brain called a hypothalamic hamartoma is characteristic of this disorder. In many cases, these growths do not cause any medical problems; however, some hypothalamic hamartomas lead to seizures or hormone abnormalities that can be life-threatening in infancy. Other features of Pallister-Hall syndrome include a malformation of the airway called a bifid epiglottis, an obstruction of the anal opening (imperforate anus), and kidney abnormalities. Although the signs and symptoms of this disorder vary from mild to severe, only a small percentage of affected people have serious complications. | Pallister-Hall syndrome |
How many people are affected by Pallister-Hall syndrome ? | This condition is very rare; its prevalence is unknown. | Pallister-Hall syndrome |
What are the genetic changes related to Pallister-Hall syndrome ? | Mutations in the GLI3 gene cause Pallister-Hall syndrome. The GLI3 gene provides instructions for making a protein that controls gene expression, which is a process that regulates whether genes are turned on or off in particular cells. By interacting with certain genes at specific times during development, the GLI3 protein plays a role in the normal shaping (patterning) of many organs and tissues before birth. Mutations that cause Pallister-Hall syndrome typically lead to the production of an abnormally short version of the GLI3 protein. Unlike the normal GLI3 protein, which can turn target genes on or off, the short protein can only turn off (repress) target genes. Researchers are working to determine how this change in the protein's function affects early development. It remains uncertain how GLI3 mutations can cause polydactyly, hypothalamic hamartoma, and the other features of Pallister-Hall syndrome. | Pallister-Hall syndrome |
Is Pallister-Hall syndrome inherited ? | 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. In some cases, an affected person inherits a mutation in the GLI3 gene from one affected parent. Other cases result from new mutations in the gene and occur in people with no history of the disorder in their family. | Pallister-Hall syndrome |
What are the treatments for Pallister-Hall syndrome ? | These resources address the diagnosis or management of Pallister-Hall syndrome: - Gene Review: Gene Review: Pallister-Hall Syndrome - Genetic Testing Registry: Pallister-Hall syndrome - MedlinePlus Encyclopedia: Epiglottis (Image) - MedlinePlus Encyclopedia: Imperforate Anus - MedlinePlus Encyclopedia: Polydactyly 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-Hall syndrome |
What is (are) persistent Mllerian duct syndrome ? | Persistent Mllerian duct syndrome is a disorder of sexual development that affects males. Males with this disorder have normal male reproductive organs, though they also have a uterus and fallopian tubes, which are female reproductive organs. The uterus and fallopian tubes are derived from a structure called the Mllerian duct during development of the fetus. The Mllerian duct usually breaks down during early development in males, but it is retained in those with persistent Mllerian duct syndrome. Affected individuals have the normal chromosomes of a male (46,XY) and normal external male genitalia. The first noted signs and symptoms in males with persistent Mllerian duct syndrome are usually undescended testes (cryptorchidism) or soft out-pouchings in the lower abdomen (inguinal hernias). The uterus and fallopian tubes are typically discovered when surgery is performed to treat these conditions. The testes and female reproductive organs can be located in unusual positions in persistent Mllerian duct syndrome. Occasionally, both testes are undescended (bilateral cryptorchidism) and the uterus is in the pelvis. More often, one testis has descended into the scrotum normally, and one has not. Sometimes, the descended testis pulls the fallopian tube and uterus into the track through which it has descended. This creates a condition called hernia uteri inguinalis, a form of inguinal hernia. In other cases, the undescended testis from the other side of the body is also pulled into the same track, forming an inguinal hernia. This condition, called transverse testicular ectopia, is common in people with persistent Mllerian duct syndrome. Other effects of persistent Mllerian duct syndrome may include the inability to father children (infertility) or blood in the semen (hematospermia). Also, the undescended testes may break down (degenerate) or develop cancer if left untreated. | persistent Mllerian duct syndrome |
How many people are affected by persistent Mllerian duct syndrome ? | Persistent Mllerian duct syndrome is a rare disorder; however, the prevalence of the condition is unknown. | persistent Mllerian duct syndrome |
What are the genetic changes related to persistent Mllerian duct syndrome ? | Most people with persistent Mllerian duct syndrome have mutations in the AMH gene or the AMHR2 gene. The AMH gene provides instructions for making a protein called anti-Mllerian hormone (AMH). The AMHR2 gene provides instructions for making a protein called AMH receptor type 2. The AMH protein and AMH receptor type 2 protein are involved in male sex differentiation. All fetuses develop the Mllerian duct, the precursor to female reproductive organs. During development of a male fetus, these two proteins work together to induce breakdown (regression) of the Mllerian duct. Mutations in the AMH and AMHR2 genes lead to nonfunctional proteins that cannot signal for regression of the Mllerian duct. As a result of these mutations, the Mllerian duct persists and goes on to form a uterus and fallopian tubes. Approximately 45 percent of cases of persistent Mllerian duct syndrome are caused by mutations in the AMH gene and are called persistent Mllerian duct syndrome type 1. Approximately 40 percent of cases are caused by mutations in the AMHR2 gene and are called persistent Mllerian duct syndrome type 2. In the remaining 15 percent of cases, no mutations in the AMH and AMHR2 genes have been identified, and the genes involved in causing the condition are unknown. | persistent Mllerian duct syndrome |
Is persistent Mllerian duct syndrome inherited ? | 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. However, persistent Mllerian duct syndrome affects only males. Females with two mutated copies of the gene do not show signs and symptoms of the condition. | persistent Mllerian duct syndrome |
What are the treatments for persistent Mllerian duct syndrome ? | These resources address the diagnosis or management of persistent Mllerian duct syndrome: - Genetic Testing Registry: Persistent Mullerian duct syndrome - MedlinePlus Encyclopedia: Undescended testicle repair 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 | persistent Mllerian duct syndrome |
What is (are) ALG1-congenital disorder of glycosylation ? | ALG1-congenital disorder of glycosylation (ALG1-CDG, also known as congenital disorder of glycosylation type Ik) is an inherited disorder with varying signs and symptoms that typically develop during infancy and can affect several body systems. Individuals with ALG1-CDG often have intellectual disability, delayed development, and weak muscle tone (hypotonia). Many affected individuals develop seizures that can be difficult to treat. Individuals with ALG1-CDG may also have movement problems such as involuntary rhythmic shaking (tremor) or difficulties with movement and balance (ataxia). People with ALG1-CDG often have problems with blood clotting, which can lead to abnormal clotting or bleeding episodes. Additionally, affected individuals may produce abnormally low levels of proteins called antibodies (or immunoglobulins), particularly immunoglobulin G (IgG). Antibodies help protect the body against infection by foreign particles and germs. A reduction in antibodies can make it difficult for affected individuals to fight infections. Some people with ALG1-CDG have physical abnormalities such as a small head size (microcephaly); unusual facial features; joint deformities called contractures; long, slender fingers and toes (arachnodactyly); or unusually fleshy pads at the tips of the fingers and toes. Eye problems that may occur in people with this condition include eyes that do not point in the same direction (strabismus) or involuntary eye movements (nystagmus). Rarely, affected individuals develop vision loss. Less common abnormalities that occur in people with ALG1-CDG include respiratory problems, reduced sensation in their arms and legs (peripheral neuropathy), swelling (edema), and gastrointestinal difficulties. The signs and symptoms of ALG1-CDG are often severe, with affected individuals surviving only into infancy or childhood. However, some people with this condition are more mildly affected and survive into adulthood. | ALG1-congenital disorder of glycosylation |
How many people are affected by ALG1-congenital disorder of glycosylation ? | ALG1-CDG appears to be a rare disorder; fewer than 30 affected individuals have been described in the scientific literature. | ALG1-congenital disorder of glycosylation |
What are the genetic changes related to ALG1-congenital disorder of glycosylation ? | Mutations in the ALG1 gene cause ALG1-CDG. This gene provides instructions for making an enzyme that is involved in a process called glycosylation. During this process, complex chains of sugar molecules (oligosaccharides) are added to proteins and fats (lipids). Glycosylation modifies proteins and lipids so they can fully perform their functions. The enzyme produced from the ALG1 gene transfers a simple sugar called mannose to growing oligosaccharides at a particular step in the formation of the sugar chain. Once the correct number of sugar molecules are linked together, the oligosaccharide is attached to a protein or lipid. ALG1 gene mutations lead to the production of an abnormal enzyme with reduced activity. The poorly functioning enzyme cannot add mannose to sugar chains efficiently, and the resulting oligosaccharides are often incomplete. Although the short oligosaccharides can be transferred to proteins and fats, the process is not as efficient as with the full-length oligosaccharide. The wide variety of signs and symptoms in ALG1-CDG are likely due to impaired glycosylation of proteins and lipids that are needed for normal function of many organs and tissues. | ALG1-congenital disorder of glycosylation |
Is ALG1-congenital disorder of glycosylation inherited ? | 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. | ALG1-congenital disorder of glycosylation |
What are the treatments for ALG1-congenital disorder of glycosylation ? | These resources address the diagnosis or management of ALG1-congenital disorder of glycosylation: - Gene Review: Gene Review: Congenital Disorders of N-Linked Glycosylation Pathway Overview - Genetic Testing Registry: Congenital disorder of glycosylation type 1K 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 | ALG1-congenital disorder of glycosylation |
What is (are) congenital hypothyroidism ? | Congenital hypothyroidism is a partial or complete loss of function of the thyroid gland (hypothyroidism) that affects infants from birth (congenital). The thyroid gland is a butterfly-shaped tissue in the lower neck. It makes iodine-containing hormones that play an important role in regulating growth, brain development, and the rate of chemical reactions in the body (metabolism). People with congenital hypothyroidism have lower-than-normal levels of these important hormones. Congenital hypothyroidism occurs when the thyroid gland fails to develop or function properly. In 80 to 85 percent of cases, the thyroid gland is absent, severely reduced in size (hypoplastic), or abnormally located. These cases are classified as thyroid dysgenesis. In the remainder of cases, a normal-sized or enlarged thyroid gland (goiter) is present, but production of thyroid hormones is decreased or absent. Most of these cases occur when one of several steps in the hormone synthesis process is impaired; these cases are classified as thyroid dyshormonogenesis. Less commonly, reduction or absence of thyroid hormone production is caused by impaired stimulation of the production process (which is normally done by a structure at the base of the brain called the pituitary gland), even though the process itself is unimpaired. These cases are classified as central (or pituitary) hypothyroidism. Signs and symptoms of congenital hypothyroidism result from the shortage of thyroid hormones. Affected babies may show no features of the condition, although some babies with congenital hypothyroidism are less active and sleep more than normal. They may have difficulty feeding and experience constipation. If untreated, congenital hypothyroidism can lead to intellectual disability and slow growth. In the United States and many other countries, all hospitals test newborns for congenital hypothyroidism. If treatment begins in the first two weeks after birth, infants usually develop normally. Congenital hypothyroidism can also occur as part of syndromes that affect other organs and tissues in the body. These forms of the condition are described as syndromic. Some common forms of syndromic hypothyroidism include Pendred syndrome, Bamforth-Lazarus syndrome, and brain-lung-thyroid syndrome. | congenital hypothyroidism |
How many people are affected by congenital hypothyroidism ? | Congenital hypothyroidism affects an estimated 1 in 2,000 to 4,000 newborns. For reasons that remain unclear, congenital hypothyroidism affects more than twice as many females as males. | congenital hypothyroidism |
What are the genetic changes related to congenital hypothyroidism ? | Congenital hypothyroidism can be caused by a variety of factors, only some of which are genetic. The most common cause worldwide is a shortage of iodine in the diet of the mother and the affected infant. Iodine is essential for the production of thyroid hormones. Genetic causes account for about 15 to 20 percent of cases of congenital hypothyroidism. The cause of the most common type of congenital hypothyroidism, thyroid dysgenesis, is usually unknown. Studies suggest that 2 to 5 percent of cases are inherited. Two of the genes involved in this form of the condition are PAX8 and TSHR. These genes play roles in the proper growth and development of the thyroid gland. Mutations in these genes prevent or disrupt normal development of the gland. The abnormal or missing gland cannot produce normal amounts of thyroid hormones. Thyroid dyshormonogenesis results from mutations in one of several genes involved in the production of thyroid hormones. These genes include DUOX2, SLC5A5, TG, and TPO. Mutations in each of these genes disrupt a step in thyroid hormone synthesis, leading to abnormally low levels of these hormones. Mutations in the TSHB gene disrupt the synthesis of thyroid hormones by impairing the stimulation of hormone production. Changes in this gene are the primary cause of central hypothyroidism. The resulting shortage of thyroid hormones disrupts normal growth, brain development, and metabolism, leading to the features of congenital hypothyroidism. Mutations in other genes that have not been as well characterized can also cause congenital hypothyroidism. Still other genes are involved in syndromic forms of the disorder. | congenital hypothyroidism |
Is congenital hypothyroidism inherited ? | Most cases of congenital hypothyroidism are sporadic, which means they occur in people with no history of the disorder in their family. When inherited, the condition usually has an autosomal recessive inheritance pattern, which means both copies of the gene in each cell have mutations. Typically, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they do not show signs and symptoms of the condition. When congenital hypothyroidism results from mutations in the PAX8 gene or from certain mutations in the TSHR or DUOX2 gene, 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 disorder. In some of these cases, an affected person inherits the mutation from one affected parent. Other cases result from new (de novo) mutations in the gene that occur during the formation of reproductive cells (eggs or sperm) or in early embryonic development. These cases occur in people with no history of the disorder in their family. | congenital hypothyroidism |
What are the treatments for congenital hypothyroidism ? | These resources address the diagnosis or management of congenital hypothyroidism: - Baby's First Test - Genetic Testing Registry: Congenital hypothyroidism - Genetic Testing Registry: Hypothyroidism, congenital, nongoitrous, 1 - MedlinePlus Encyclopedia: Congenital Hypothyroidism 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 | congenital hypothyroidism |
What is (are) Donohue syndrome ? | 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 |
How many people are affected by Donohue syndrome ? | Donohue syndrome is estimated to affect less than 1 per million people worldwide. Several dozen cases have been reported in the medical literature. | Donohue syndrome |
What are the genetic changes related to Donohue syndrome ? | 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. | Donohue syndrome |
Is Donohue syndrome inherited ? | 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. | Donohue syndrome |
What are the treatments for Donohue syndrome ? | These resources address the diagnosis or management of Donohue syndrome: - Genetic Testing Registry: Leprechaunism 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 | Donohue syndrome |
What is (are) hyperprolinemia ? | Hyperprolinemia is an excess of a particular protein building block (amino acid), called proline, in the blood. This condition generally occurs when proline is not broken down properly by the body. There are two inherited forms of hyperprolinemia, called type I and type II. People with hyperprolinemia type I often do not show any symptoms, although they have proline levels in their blood between 3 and 10 times the normal level. Some individuals with hyperprolinemia type I exhibit seizures, intellectual disability, or other neurological or psychiatric problems. Hyperprolinemia type II results in proline levels in the blood between 10 and 15 times higher than normal, and high levels of a related compound called pyrroline-5-carboxylate. This form of the disorder has signs and symptoms that vary in severity, and is more likely than type I to involve seizures or intellectual disability. Hyperprolinemia can also occur with other conditions, such as malnutrition or liver disease. In particular, individuals with conditions that cause elevated levels of lactic acid in the blood (lactic acidemia) may have hyperprolinemia as well, because lactic acid inhibits the breakdown of proline. | hyperprolinemia |
How many people are affected by hyperprolinemia ? | It is difficult to determine the prevalence of hyperprolinemia type I because most people with the condition do not have any symptoms. Hyperprolinemia type II is a rare condition; its prevalence is also unknown. | hyperprolinemia |
What are the genetic changes related to hyperprolinemia ? | Mutations in the ALDH4A1 and PRODH genes cause hyperprolinemia. Inherited hyperprolinemia is caused by deficiencies in the enzymes that break down (degrade) proline. Hyperprolinemia type I is caused by a mutation in the PRODH gene, which provides instructions for producing the enzyme proline oxidase. This enzyme begins the process of degrading proline by starting the reaction that converts it to pyrroline-5-carboxylate. Hyperprolinemia type II is caused by a mutation in the ALDH4A1 gene, which provides instructions for producing the enzyme pyrroline-5-carboxylate dehydrogenase. This enzyme helps to break down the pyrroline-5-carboxylate produced in the previous reaction, converting it to the amino acid glutamate. The conversion between proline and glutamate, and the reverse reaction controlled by different enzymes, are important in maintaining a supply of the amino acids needed for protein production, and for energy transfer within the cell. A deficiency of either proline oxidase or pyrroline-5-carboxylate dehydrogenase results in a buildup of proline in the body. A deficiency of the latter enzyme leads to higher levels of proline and a buildup of the intermediate breakdown product pyrroline-5-carboxylate, causing the signs and symptoms of hyperprolinemia type II. | hyperprolinemia |
Is hyperprolinemia inherited ? | 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 condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. In about one-third of cases, individuals carrying one copy of an altered PRODH gene have moderately elevated levels of proline in their blood, but these levels do not cause any health problems. Individuals with one altered ALDH4A1 gene have normal levels of proline in their blood. | hyperprolinemia |
What are the treatments for hyperprolinemia ? | These resources address the diagnosis or management of hyperprolinemia: - Baby's First Test - Genetic Testing Registry: Deficiency of pyrroline-5-carboxylate reductase - Genetic Testing Registry: Proline 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 | hyperprolinemia |
What is (are) triple A syndrome ? | Triple A syndrome is an inherited condition characterized by three specific features: achalasia, Addison disease, and alacrima. Achalasia is a disorder that affects the ability to move food through the esophagus, the tube that carries food from the throat to the stomach. It can lead to severe feeding difficulties and low blood sugar (hypoglycemia). Addison disease, also known as primary adrenal insufficiency, is caused by abnormal function of the small hormone-producing glands on top of each kidney (adrenal glands). The main features of Addison disease include fatigue, loss of appetite, weight loss, low blood pressure, and darkening of the skin. The third major feature of triple A syndrome is a reduced or absent ability to secrete tears (alacrima). Most people with triple A syndrome have all three of these features, although some have only two. Many of the features of triple A syndrome are caused by dysfunction of the autonomic nervous system. This part of the nervous system controls involuntary body processes such as digestion, blood pressure, and body temperature. People with triple A syndrome often experience abnormal sweating, difficulty regulating blood pressure, unequal pupil size (anisocoria), and other signs and symptoms of autonomic nervous system dysfunction (dysautonomia). People with this condition may have other neurological abnormalities, such as developmental delay, intellectual disability, speech problems (dysarthria), and a small head size (microcephaly). In addition, affected individuals commonly experience muscle weakness, movement problems, and nerve abnormalities in their extremities (peripheral neuropathy). Some develop optic atrophy, which is the degeneration (atrophy) of the nerves that carry information from the eyes to the brain. Many of the neurological symptoms of triple A syndrome worsen over time. People with triple A syndrome frequently develop a thickening of the outer layer of skin (hyperkeratosis) on the palms of their hands and the soles of their feet. Other skin abnormalities may also be present in people with this condition. Alacrima is usually the first noticeable sign of triple A syndrome, as it becomes apparent early in life that affected children produce little or no tears while crying. They develop Addison disease and achalasia during childhood or adolescence, and most of the neurologic features of triple A syndrome begin during adulthood. The signs and symptoms of this condition vary among affected individuals, even among members of the same family. | triple A syndrome |
How many people are affected by triple A syndrome ? | Triple A syndrome is a rare condition, although its exact prevalence is unknown. | triple A syndrome |
What are the genetic changes related to triple A syndrome ? | Mutations in the AAAS gene cause triple A syndrome. This gene provides instructions for making a protein called ALADIN whose function is not well understood. Within cells, ALADIN is found in the nuclear envelope, the structure that surrounds the nucleus and separates it from the rest of the cell. Based on its location, ALADIN is thought to be involved in the movement of molecules into and out of the nucleus. Mutations in the AAAS gene change the structure of ALADIN in different ways; however, almost all mutations prevent this protein from reaching its proper location in the nuclear envelope. The absence of ALADIN in the nuclear envelope likely disrupts the movement of molecules across this membrane. Researchers suspect that DNA repair proteins may be unable to enter the nucleus if ALADIN is missing from the nuclear envelope. DNA damage that is not repaired can cause the cell to become unstable and lead to cell death. Although the nervous system is particularly vulnerable to DNA damage, it remains unknown exactly how mutations in the AAAS gene lead to the signs and symptoms of triple A syndrome. Some individuals with triple A syndrome do not have an identified mutation in the AAAS gene. The genetic cause of the disorder is unknown in these individuals. | triple A syndrome |
Is triple A syndrome inherited ? | 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. | triple A syndrome |
What are the treatments for triple A syndrome ? | These resources address the diagnosis or management of triple A syndrome: - Genetic Testing Registry: Glucocorticoid deficiency with achalasia - MedlinePlus Encyclopedia: Achalasia - MedlinePlus Encyclopedia: Anisocoria 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 | triple A syndrome |
What is (are) atypical hemolytic-uremic syndrome ? | Atypical hemolytic-uremic syndrome is a disease that primarily affects kidney function. This condition, which can occur at any age, causes abnormal blood clots (thrombi) to form in small blood vessels in the kidneys. These clots can cause serious medical problems if they restrict or block blood flow. Atypical hemolytic-uremic syndrome is characterized by three major features related to abnormal clotting: hemolytic anemia, thrombocytopenia, and kidney failure. Hemolytic anemia occurs when red blood cells break down (undergo hemolysis) prematurely. In atypical hemolytic-uremic syndrome, red blood cells can break apart as they squeeze past clots within small blood vessels. Anemia results if these cells are destroyed faster than the body can replace them. This condition can lead to unusually pale skin (pallor), yellowing of the eyes and skin (jaundice), fatigue, shortness of breath, and a rapid heart rate. Thrombocytopenia is a reduced level of circulating platelets, which are cell fragments that normally assist with blood clotting. In people with atypical hemolytic-uremic syndrome, fewer platelets are available in the bloodstream because a large number of platelets are used to make abnormal clots. Thrombocytopenia can cause easy bruising and abnormal bleeding. As a result of clot formation in small blood vessels, people with atypical hemolytic-uremic syndrome experience kidney damage and acute kidney failure that lead to end-stage renal disease (ESRD) in about half of all cases. These life-threatening complications prevent the kidneys from filtering fluids and waste products from the body effectively. Atypical hemolytic-uremic syndrome should be distinguished from a more common condition called typical hemolytic-uremic syndrome. The two disorders have different causes and different signs and symptoms. Unlike the atypical form, the typical form is caused by infection with certain strains of Escherichia coli bacteria that produce toxic substances called Shiga-like toxins. The typical form is characterized by severe diarrhea and most often affects children younger than 10. The typical form is less likely than the atypical form to involve recurrent attacks of kidney damage that lead to ESRD. | atypical hemolytic-uremic syndrome |
How many people are affected by atypical hemolytic-uremic syndrome ? | The incidence of atypical hemolytic-uremic syndrome is estimated to be 1 in 500,000 people per year in the United States. The atypical form is probably about 10 times less common than the typical form. | atypical hemolytic-uremic syndrome |
What are the genetic changes related to atypical hemolytic-uremic syndrome ? | Atypical hemolytic-uremic syndrome often results from a combination of environmental and genetic factors. Mutations in at least seven genes appear to increase the risk of developing the disorder. Mutations in a gene called CFH are most common; they have been found in about 30 percent of all cases of atypical hemolytic-uremic syndrome. Mutations in the other genes have each been identified in a smaller percentage of cases. The genes associated with atypical hemolytic-uremic syndrome provide instructions for making proteins involved in a part of the body's immune response known as the complement system. This system is a group of proteins that work together to destroy foreign invaders (such as bacteria and viruses), trigger inflammation, and remove debris from cells and tissues. The complement system must be carefully regulated so it targets only unwanted materials and does not attack the body's healthy cells. The regulatory proteins associated with atypical hemolytic-uremic syndrome protect healthy cells by preventing activation of the complement system when it is not needed. Mutations in the genes associated with atypical hemolytic-uremic syndrome lead to uncontrolled activation of the complement system. The overactive system attacks cells that line blood vessels in the kidneys, causing inflammation and the formation of abnormal clots. These abnormalities lead to kidney damage and, in many cases, kidney failure and ESRD. Although gene mutations increase the risk of atypical hemolytic-uremic syndrome, studies suggest that they are often not sufficient to cause the disease. In people with certain genetic changes, the signs and symptoms of the disorder may be triggered by factors including certain medications (such as anticancer drugs), chronic diseases, viral or bacterial infections, cancers, organ transplantation, or pregnancy. Some people with atypical hemolytic-uremic syndrome do not have any known genetic changes or environmental triggers for the disease. In these cases, the disorder is described as idiopathic. | atypical hemolytic-uremic syndrome |
Is atypical hemolytic-uremic syndrome inherited ? | Most cases of atypical hemolytic-uremic syndrome are sporadic, which means that they occur in people with no apparent history of the disorder in their family. Less than 20 percent of all cases have been reported to run in families. When the disorder is familial, it can have an autosomal dominant or an autosomal recessive pattern of inheritance. Autosomal dominant inheritance means one copy of an altered gene in each cell is sufficient to increase the risk of the disorder. In some cases, an affected person inherits the mutation from one affected parent. However, most people with the autosomal dominant form of atypical hemolytic-uremic syndrome have no history of the disorder in their family. Because not everyone who inherits a gene mutation will develop the signs and symptoms of the disease, an affected individual may have unaffected relatives who carry a copy of the mutation. Autosomal recessive inheritance means both copies of a 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. | atypical hemolytic-uremic syndrome |
What are the treatments for atypical hemolytic-uremic syndrome ? | These resources address the diagnosis or management of atypical hemolytic-uremic syndrome: - Gene Review: Gene Review: Atypical Hemolytic-Uremic Syndrome - Genetic Testing Registry: Atypical hemolytic uremic syndrome - Genetic Testing Registry: Atypical hemolytic-uremic syndrome 1 - Genetic Testing Registry: Atypical hemolytic-uremic syndrome 2 - Genetic Testing Registry: Atypical hemolytic-uremic syndrome 3 - Genetic Testing Registry: Atypical hemolytic-uremic syndrome 4 - Genetic Testing Registry: Atypical hemolytic-uremic syndrome 5 - Genetic Testing Registry: Atypical hemolytic-uremic syndrome 6 - MedlinePlus Encyclopedia: Hemolytic Anemia - MedlinePlus Encyclopedia: Hemolytic-Uremic Syndrome - MedlinePlus Encyclopedia: Thrombocytopenia - National Institute of Diabetes and Digestive and Kidney Diseases: Kidney Failure: Choosing a Treatment That's Right for You 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 | atypical hemolytic-uremic syndrome |
What is (are) hereditary folate malabsorption ? | Hereditary folate malabsorption is a disorder that interferes with the body's ability to absorb certain B vitamins (called folates) from food. Folates are important for many cell functions, including the production of DNA and its chemical cousin, RNA. Infants with hereditary folate malabsorption are born with normal amounts of folates in their body because they obtain these vitamins from their mother's blood before birth. They generally begin to show signs and symptoms of the disorder within the first few months of life because their ability to absorb folates from food is impaired. Infants with hereditary folate malabsorption experience feeding difficulties, diarrhea, and failure to gain weight and grow at the expected rate (failure to thrive). Affected individuals usually develop a blood disorder called megaloblastic anemia. Megaloblastic anemia occurs when a person has a low number of red blood cells (anemia), and the remaining red blood cells are larger than normal (megaloblastic). The symptoms of this blood disorder may include decreased appetite, lack of energy, headaches, pale skin, and tingling or numbness in the hands and feet. People with hereditary folate malabsorption may also have a deficiency of white blood cells (leukopenia), leading to increased susceptibility to infections. In addition, they may have a reduction in the amount of platelets (thrombocytopenia), which can result in easy bruising and abnormal bleeding. Some infants with hereditary folate malabsorption exhibit neurological problems such as developmental delay and seizures. Over time, untreated individuals may develop intellectual disability and difficulty coordinating movements (ataxia). | hereditary folate malabsorption |
How many people are affected by hereditary folate malabsorption ? | The prevalence of hereditary folate malabsorption is unknown. Approximately 15 affected families have been reported worldwide. Researchers believe that some infants with this disorder may not get diagnosed or treated, particularly in areas where advanced medical care is not available. | hereditary folate malabsorption |
What are the genetic changes related to hereditary folate malabsorption ? | The SLC46A1 gene provides instructions for making a protein called the proton-coupled folate transporter (PCFT). PCFT is important for normal functioning of intestinal epithelial cells, which are cells that line the walls of the intestine. These cells have fingerlike projections called microvilli that absorb nutrients from food as it passes through the intestine. Based on their appearance, groups of these microvilli are known collectively as the brush border. PCFT is involved in the process of using energy to move folates across the brush border membrane, a mechanism called active transport. It is also involved in the transport of folates between the brain and the fluid that surrounds it (cerebrospinal fluid). Mutations in the SLC46A1 gene result in a PCFT protein that has little or no activity. In some cases the mutated protein is not transported to the cell membrane, and so it is unable to perform its function. A lack of functional PCFT impairs the body's ability to absorb folates from food, resulting in the signs and symptoms of hereditary folate malabsorption. | hereditary folate malabsorption |
Is hereditary folate malabsorption inherited ? | 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. | hereditary folate malabsorption |
What are the treatments for hereditary folate malabsorption ? | These resources address the diagnosis or management of hereditary folate malabsorption: - Gene Review: Gene Review: Hereditary Folate Malabsorption - Genetic Testing Registry: Congenital defect of folate absorption - MedlinePlus Encyclopedia: Folate - MedlinePlus Encyclopedia: Folate Deficiency - MedlinePlus Encyclopedia: Folate-Deficiency Anemia - MedlinePlus Encyclopedia: Malabsorption 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 | hereditary folate malabsorption |
What is (are) laryngo-onycho-cutaneous syndrome ? | Laryngo-onycho-cutaneous (LOC) syndrome is a disorder that leads to abnormalities of the voicebox (laryngo-), finger- and toenails (onycho-), and skin (cutaneous). Many of the condition's signs and symptoms are related to the abnormal growth of granulation tissue in different parts of the body. This red, bumpy tissue is normally produced during wound healing and is usually replaced by skin cells as healing continues. However, in people with LOC syndrome, this tissue grows even when there is no major injury. One of the first symptoms in infants with LOC syndrome is a hoarse cry due to ulcers or overgrowth of granulation tissue in the voicebox (the larynx). Excess granulation tissue can also block the airways, leading to life-threatening breathing problems; as a result many affected individuals do not survive past childhood. In LOC syndrome, granulation tissue also grows in the eyes, specifically the conjunctiva, which are the moist tissues that line the eyelids and the white part of the eyes. Affected individuals often have impairment or complete loss of vision due to the tissue overgrowth. Another common feature of LOC syndrome is missing patches of skin (cutaneous erosions). The erosions heal slowly and may become infected. People with LOC syndrome can also have malformed nails and small, abnormal teeth. The hard, white material that forms the protective outer layer of each tooth (enamel) is thin, which contributes to frequent cavities. LOC syndrome is typically considered a subtype of another skin condition called junctional epidermolysis bullosa, which is characterized by fragile skin that blisters easily. While individuals with junctional epidermolysis bullosa can have some of the features of LOC syndrome, they do not usually have overgrowth of granulation tissue in the conjunctiva. | laryngo-onycho-cutaneous syndrome |
How many people are affected by laryngo-onycho-cutaneous syndrome ? | LOC syndrome is a rare disorder that primarily affects families of Punjabi background from India and Pakistan, although the condition has also been reported in one family from Iran. | laryngo-onycho-cutaneous syndrome |
What are the genetic changes related to laryngo-onycho-cutaneous syndrome ? | LOC syndrome is caused by mutations in the LAMA3 gene, which provides instructions for making one part (subunit) of a protein called laminin 332. This protein is made up of three subunits, called alpha, beta, and gamma. The LAMA3 gene carries instructions for the alpha subunit; the beta and gamma subunits are produced from other genes. The laminin 332 protein plays an important role in strengthening and stabilizing the skin by helping to attach the top layer of skin (the epidermis) to underlying layers. Studies suggest that laminin 332 is also involved in wound healing. Additionally, researchers have proposed roles for laminin 332 in the clear outer covering of the eye (the cornea) and in the development of tooth enamel. The mutations involved in LOC syndrome alter the structure of one version of the alpha subunit of laminin 332 (called alpha-3a). Laminins made with the altered subunit cannot effectively attach the epidermis to underlying layers of skin or regulate wound healing. These abnormalities of laminin 332 cause the cutaneous erosions and overgrowth of granulation tissue that are characteristic of LOC syndrome. The inability of laminin 332 to perform its other functions leads to the nail and tooth abnormalities that occur in this condition. | laryngo-onycho-cutaneous syndrome |
Is laryngo-onycho-cutaneous syndrome inherited ? | 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. | laryngo-onycho-cutaneous syndrome |
What are the treatments for laryngo-onycho-cutaneous syndrome ? | These resources address the diagnosis or management of laryngo-onycho-cutaneous syndrome: - Genetic Testing Registry: Laryngoonychocutaneous 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 | laryngo-onycho-cutaneous syndrome |
What is (are) gastrointestinal stromal tumor ? | A gastrointestinal stromal tumor (GIST) is a type of tumor that occurs in the gastrointestinal tract, most commonly in the stomach or small intestine. The tumors are thought to grow from specialized cells found in the gastrointestinal tract called interstitial cells of Cajal (ICCs) or precursors to these cells. GISTs are usually found in adults between ages 40 and 70; rarely, children and young adults develop these tumors. The tumors can be cancerous (malignant) or noncancerous (benign). Small tumors may cause no signs or symptoms. However, some people with GISTs may experience pain or swelling in the abdomen, nausea, vomiting, loss of appetite, or weight loss. Sometimes, tumors cause bleeding, which may lead to low red blood cell counts (anemia) and, consequently, weakness and tiredness. Bleeding into the intestinal tract may cause black and tarry stools, and bleeding into the throat or stomach may cause vomiting of blood. Affected individuals with no family history of GIST typically have only one tumor (called a sporadic GIST). People with a family history of GISTs (called familial GISTs) often have multiple tumors and additional signs or symptoms, including noncancerous overgrowth (hyperplasia) of other cells in the gastrointestinal tract and patches of dark skin on various areas of the body. Some affected individuals have a skin condition called urticaria pigmentosa (also known as cutaneous mastocytosis), which is characterized by raised patches of brownish skin that sting or itch when touched. | gastrointestinal stromal tumor |
How many people are affected by gastrointestinal stromal tumor ? | Approximately 5,000 new cases of GIST are diagnosed in the United States each year. However, GISTs may be more common than this estimate because small tumors may remain undiagnosed. | gastrointestinal stromal tumor |
What are the genetic changes related to gastrointestinal stromal tumor ? | Genetic changes in one of several genes are involved in the formation of GISTs. About 80 percent of cases are associated with a mutation in the KIT gene, and about 10 percent of cases are associated with a mutation in the PDGFRA gene. Mutations in the KIT and PDGFRA genes are associated with both familial and sporadic GISTs. A small number of affected individuals have mutations in other genes. The KIT and PDGFRA genes provide instructions for making receptor proteins that are found in the cell membrane of certain cell types and stimulate signaling pathways inside the cell. Receptor proteins have specific sites into which certain other proteins, called ligands, fit like keys into locks. When the ligand attaches (binds), the KIT or PDGFRA receptor protein is turned on (activated), which leads to activation of a series of proteins in multiple signaling pathways. These signaling pathways control many important cellular processes, such as cell growth and division (proliferation) and survival. Mutations in the KIT and PDGFRA genes lead to proteins that no longer require ligand binding to be activated. As a result, the proteins and the signaling pathways are constantly turned on (constitutively activated), which increases the proliferation and survival of cells. When these mutations occur in ICCs or their precursors, the uncontrolled cell growth leads to GIST formation. | gastrointestinal stromal tumor |
Is gastrointestinal stromal tumor inherited ? | Most cases of GIST are not inherited. Sporadic GIST is associated with somatic mutations, which are genetic changes that occur only in the tumor cells and occur during a person's lifetime. In some cases of familial GIST, including those associated with mutations in the KIT and PDGFRA genes, mutations are inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to increase a person's chance of developing tumors. When familial GIST is associated with mutations in other genes, it can have an autosomal recessive pattern of inheritance, which means alterations in both copies of the gene in each cell increase a person's chance of developing tumors. | gastrointestinal stromal tumor |
What are the treatments for gastrointestinal stromal tumor ? | These resources address the diagnosis or management of gastrointestinal stromal tumor: - American Cancer Society: Treating Gastrointestinal Stromal Tumor (GIST) - Cancer.Net: Gastrointestinal Stromal Tumor--Diagnosis - Genetic Testing Registry: Gastrointestinal stromal tumor 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 | gastrointestinal stromal tumor |
What is (are) spastic paraplegia type 31 ? | Spastic paraplegia type 31 is one of a group of genetic disorders known as hereditary spastic paraplegias. These disorders are characterized by progressive muscle stiffness (spasticity) and the development of paralysis of the lower limbs (paraplegia) caused by degeneration of nerve cells (neurons) that trigger muscle movement. Hereditary spastic paraplegias are divided into two types: pure and complicated. The pure types involve only the lower limbs, while the complicated types also involve the upper limbs and other areas of the body, including the brain. Spastic paraplegia type 31 is usually a pure hereditary spastic paraplegia, although a few complicated cases have been reported. The first signs and symptoms of spastic paraplegia type 31 usually appear before age 20 or after age 30. An early feature is difficulty walking due to spasticity and weakness, which typically affect both legs equally. People with spastic paraplegia type 31 can also experience progressive muscle wasting (amyotrophy) in the lower limbs, exaggerated reflexes (hyperreflexia), a decreased ability to feel vibrations, reduced bladder control, and high-arched feet (pes cavus). As the condition progresses, some individuals require walking support. | spastic paraplegia type 31 |
How many people are affected by spastic paraplegia type 31 ? | Spastic paraplegia type 31 is one of a subgroup of hereditary spastic paraplegias known as autosomal dominant hereditary spastic paraplegia, which has an estimated prevalence of one to 12 per 100,000 individuals. Spastic paraplegia type 31 accounts for 3 to 9 percent of all autosomal dominant hereditary spastic paraplegia cases. | spastic paraplegia type 31 |
What are the genetic changes related to spastic paraplegia type 31 ? | Spastic paraplegia type 31 is caused by mutations in the REEP1 gene. This gene provides instructions for making a protein called receptor expression-enhancing protein 1 (REEP1), which is found in neurons in the brain and spinal cord. The REEP1 protein is located within cell compartments called mitochondria, which are the energy-producing centers in cells, and the endoplasmic reticulum, which helps with protein processing and transport. The REEP1 protein plays a role in regulating the size of the endoplasmic reticulum and determining how many proteins it can process. The function of the REEP1 protein in the mitochondria is unknown. REEP1 gene mutations that cause spastic paraplegia type 31 result in a short, nonfunctional protein that is usually broken down quickly. As a result, there is a reduction in functional REEP1 protein. It is unclear how REEP1 gene mutations lead to the signs and symptoms of spastic paraplegia type 31. Researchers have shown that mitochondria in cells of affected individuals are less able to produce energy, which may contribute to the death of neurons and lead to the progressive movement problems of spastic paraplegia type 31; however, the exact mechanism that causes this condition is unknown. | spastic paraplegia type 31 |
Is spastic paraplegia type 31 inherited ? | 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. | spastic paraplegia type 31 |
What are the treatments for spastic paraplegia type 31 ? | These resources address the diagnosis or management of spastic paraplegia type 31: - Gene Review: Gene Review: Hereditary Spastic Paraplegia Overview - Genetic Testing Registry: Spastic paraplegia 31, autosomal dominant - Spastic Paraplegia Foundation, Inc.: Treatments and Therapies 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 | spastic paraplegia type 31 |
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