Druvith/medqa huggingface dataset:
What is (are) vitamin D-dependent rickets ? 

Vitamin D-dependent rickets is a disorder of bone development that leads to softening and weakening of the bones (rickets). The condition is split into two major types: type 1 (VDDR1), which is also known as pseudovitamin D deficiency rickets or vitamin D 1-hydroxylase deficiency, and type 2 (VDDR2), also known as hereditary vitamin D-resistant rickets (HVDRR).  The signs and symptoms of this condition begin within months of birth, and most are the same for VDDR1 and VDDR2. The weak bones often cause bone pain and delayed growth and have a tendency to fracture. When affected children begin to walk, they may develop bowed legs because the bones are too weak to bear weight. Impaired bone development also results in widening of the areas near the ends of bones where new bone forms (metaphyses), especially in the knees, wrists, and ribs. Some people with vitamin D-dependent rickets have dental abnormalities such as thin tooth enamel and frequent cavities. Poor muscle tone (hypotonia) and muscle weakness are also common in this condition, and some affected individuals develop seizures.  In vitamin D-dependent rickets, there is an imbalance of certain substances in the blood. Both VDDR1 and VDDR2 are characterized by low levels of the minerals calcium (hypocalcemia) and phosphate (hypophosphatemia), which are essential for the normal formation of bones and teeth. Affected individuals also have high levels of a hormone involved in regulating calcium levels called parathyroid hormone (PTH), which leads to a condition called secondary hyperparathyroidism. The two forms of vitamin D-dependent rickets can be distinguished by blood levels of a hormone called calcitriol, which is the active form of vitamin D; individuals with VDDR1 have abnormally low levels of calcitriol and individuals with VDDR2 have abnormally high levels.  Hair loss (alopecia) can occur in VDDR2, although not everyone with this form of the condition has alopecia. Affected individuals can have sparse or patchy hair or no hair at all on their heads. Some affected individuals are missing body hair as well.
How many people are affected by vitamin D-dependent rickets ? 

Rickets affects an estimated 1 in 200,000 children. The condition is most often caused by a lack of vitamin D in the diet or insufficient sun exposure rather than genetic mutations; genetic forms of rickets, including VDDR1 and VDDR2, are much less common. The prevalence of VDDR1 and VDDR2 is unknown. VDDR1 is more common in the French Canadian population than in other populations.
What are the genetic changes related to vitamin D-dependent rickets ? 

The two types of vitamin D-dependent rickets have different genetic causes: CYP27B1 gene mutations cause VDDR1, and VDR gene mutations cause VDDR2. Both genes are involved in the body's response to vitamin D, an important vitamin that can be can be acquired from foods in the diet or made by the body with the help of sunlight. Vitamin D helps maintain the proper balance of several minerals in the body, including calcium and phosphate. One of vitamin D's major roles is to control the absorption of calcium and phosphate from the intestines into the bloodstream.  The CYP27B1 gene provides instructions for making an enzyme called 1-alpha-hydroxylase (1-hydroxylase). This enzyme carries out the final reaction to convert vitamin D to its active form, calcitriol. Once converted, calcitriol attaches (binds) to a protein called vitamin D receptor (VDR), which is produced from the VDR gene. The resulting calcitriol-VDR complex then binds to particular regions of DNA and regulates the activity of vitamin D-responsive genes. By turning these genes on or off, VDR helps control the absorption of calcium and phosphate and other processes that regulate calcium levels in the body. VDR is also involved in hair growth through a process that does not require calcitriol binding.  Mutations in either of these genes prevent the body from responding to vitamin D. CYP27B1 gene mutations reduce or eliminate 1-hydroxylase activity, which means vitamin D is not converted to its active form. The absence of calcitriol means vitamin D-responsive genes are not turned on (activated). VDR gene mutations alter the vitamin D receptor so that it cannot regulate gene activity, regardless of the presence of calcitriol in the body; often the altered receptor cannot interact with calcitriol or with DNA.  Without activation of vitamin D-responsive genes, absorption of calcium and phosphate falls, leading to hypocalcemia and hypophosphatemia. The lack of calcium and phosphate slows the deposition of these minerals in developing bones (bone mineralization), which leads to soft, weak bones and other features of vitamin D-dependent rickets. Low levels of calcium stimulate production of PTH, resulting in secondary hyperparathyroidism; hypocalcemia can also cause muscle weakness and seizures in individuals with vitamin D-dependent rickets. Certain abnormalities in the VDR protein also impair hair growth, causing alopecia in some people with VDDR2.
Is vitamin D-dependent rickets 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.
What are the treatments for vitamin D-dependent rickets ? 

These resources address the diagnosis or management of vitamin D-dependent rickets:  - Genetic Testing Registry: Vitamin D-dependent rickets, type 1  - Genetic Testing Registry: Vitamin D-dependent rickets, type 2  - Genetic Testing Registry: Vitamin d-dependent rickets, type 2b, with normal vitamin d receptor   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
What is (are) 1q21.1 microdeletion ? 

1q21.1 microdeletion is a chromosomal change in which a small piece of chromosome 1 is deleted in each cell. The deletion occurs on the long (q) arm of the chromosome in a region designated q21.1. This chromosomal change increases the risk of delayed development, intellectual disability, physical abnormalities, and neurological and psychiatric problems. However, some people with a 1q21.1 microdeletion do not appear to have any associated features.  About 75 percent of all children with a 1q21.1 microdeletion have delayed development, particularly affecting the development of motor skills such as sitting, standing, and walking. The intellectual disability and learning problems associated with this genetic change are usually mild.  Distinctive facial features can also be associated with 1q21.1 microdeletions. The changes are usually subtle and can include a prominent forehead; a large, rounded nasal tip; a long space between the nose and upper lip (philtrum); and a high, arched roof of the mouth (palate). Other common signs and symptoms of 1q21.1 microdeletions include an unusually small head (microcephaly), short stature, and eye problems such as clouding of the lenses (cataracts). Less frequently, 1q21.1 microdeletions are associated with heart defects, abnormalities of the genitalia or urinary system, bone abnormalities (particularly in the hands and feet), and hearing loss.  Neurological problems that have been reported in people with a 1q21.1 microdeletion include seizures and weak muscle tone (hypotonia). Psychiatric or behavioral problems affect a small percentage of people with this genetic change. These include developmental conditions called autism spectrum disorders that affect communication and social interaction, attention deficit hyperactivity disorder (ADHD), and sleep disturbances. Studies suggest that deletions of genetic material from the 1q21.1 region may also be risk factors for schizophrenia.  Some people with a 1q21.1 microdeletion do not have any of the intellectual, physical, or psychiatric features described above. In these individuals, the microdeletion is often detected when they undergo genetic testing because they have a relative with the chromosomal change. It is unknown why 1q21.1 microdeletions cause cognitive and physical changes in some individuals but few or no health problems in others, even within the same family.
How many people are affected by 1q21.1 microdeletion ? 

1q21.1 microdeletion is a rare chromosomal change; only a few dozen individuals with this deletion have been reported in the medical literature.
What are the genetic changes related to 1q21.1 microdeletion ? 

Most people with a 1q21.1 microdeletion are missing a sequence of about 1.35 million DNA building blocks (base pairs), also written as 1.35 megabases (Mb), in the q21.1 region of chromosome 1. However, the exact size of the deleted region varies. This deletion affects one of the two copies of chromosome 1 in each cell.  The signs and symptoms that can result from a 1q21.1 microdeletion are probably related to the loss of several genes in this region. Researchers are working to determine which missing genes contribute to the specific features associated with the deletion. Because some people with a 1q21.1 microdeletion have no obvious related features, additional genetic or environmental factors are thought to be involved in the development of signs and symptoms.  Researchers sometimes refer to 1q21.1 microdeletion as the recurrent distal 1.35-Mb deletion to distinguish it from the genetic change that causes thrombocytopenia-absent radius syndrome (TAR syndrome). TAR syndrome results from the deletion of a different, smaller DNA segment in the chromosome 1q21.1 region near the area where the 1.35-Mb deletion occurs. The chromosomal change related to TAR syndrome is often called the 200-kb deletion.
Is 1q21.1 microdeletion inherited ? 

1q21.1 microdeletion is inherited in an autosomal dominant pattern, which means that missing genetic material from one of the two copies of chromosome 1 in each cell is sufficient to increase the risk of delayed development, intellectual disability, and other signs and symptoms.  In at least half of cases, individuals with a 1q21.1 microdeletion inherit the chromosomal change from a parent. In general, parents who carry a 1q21.1 microdeletion have milder signs and symptoms than their children who inherit the deletion, even though the deletion is the same size. About one-quarter of these parents have no associated features.  A 1q21.1 microdeletion can also occur in people whose parents do not carry the chromosomal change. In this situation, the deletion occurs most often as a random event during the formation of reproductive cells (eggs or sperm) in a parent or in early embryonic development.
What are the treatments for 1q21.1 microdeletion ? 

These resources address the diagnosis or management of 1q21.1 microdeletion:  - Gene Review: Gene Review: 1q21.1 Recurrent Microdeletion  - Genetic Testing Registry: 1q21.1 recurrent microdeletion   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
What is (are) autosomal recessive hyper-IgE syndrome ? 

Autosomal recessive hyper-IgE syndrome (AR-HIES) is a disorder of the immune system. A hallmark feature of the condition is recurrent infections that are severe and can be life-threatening. Skin infections can be caused by bacteria, viruses, or fungi. These infections cause rashes, blisters, accumulations of pus (abscesses), open sores, and scaling. People with AR-HIES also tend to have frequent bouts of pneumonia and other respiratory tract infections.  Other immune system-related problems in people with AR-HIES include an inflammatory skin disorder called eczema, food or environmental allergies, and asthma. In some affected individuals, the immune system malfunctions and attacks the body's own tissues and organs, causing autoimmune disease. For example, autoimmunity can lead to abnormal destruction of red blood cells (hemolytic anemia) in people with AR-HIES.  AR-HIES is characterized by abnormally high levels of an immune system protein called immunoglobulin E (IgE) in the blood; the levels are more than 10 times higher than normal. IgE normally triggers an immune response against foreign invaders in the body, particularly parasitic worms, and plays a role in allergies. It is unclear why people with AR-HIES have such high levels of this protein. People with AR-HIES also have highly elevated numbers of certain white blood cells called eosinophils (hypereosinophilia). Eosinophils aid in the immune response and are involved in allergic reactions.  Some people with AR-HIES have neurological problems, such as paralysis that affects the face or one side of the body (hemiplegia). Blockage of blood flow in the brain or abnormal bleeding in the brain, both of which can lead to stroke, can also occur in AR-HIES.  People with AR-HIES have a greater-than-average risk of developing cancer, particularly cancers of the blood or skin.
How many people are affected by autosomal recessive hyper-IgE syndrome ? 

AR-HIES is a rare disorder whose prevalence is unknown.
What are the genetic changes related to autosomal recessive hyper-IgE syndrome ? 

AR-HIES is usually caused by mutations in the DOCK8 gene. The protein produced from this gene plays a critical role in the survival and function of several types of immune system cells. One of the protein's functions is to help maintain the structure and integrity of immune cells called T cells and NK cells, which recognize and attack foreign invaders, particularly as these cells travel to sites of infection within the body. In addition, DOCK8 is involved in chemical signaling pathways that stimulate other immune cells called B cells to mature and produce antibodies, which are specialized proteins that attach to foreign particles and germs, marking them for destruction.  DOCK8 gene mutations result in the production of little or no functional DOCK8 protein. Shortage of this protein impairs normal immune cell development and function. It is thought that T cells and NK cells lacking DOCK8 cannot maintain their shape as they move through dense spaces, such as those found within the skin. The abnormal cells die, resulting in reduced numbers of these cells. A shortage of these immune cells impairs the immune response to foreign invaders, accounting for the severe viral skin infections common in AR-HIES. A lack of DOCK8 also impairs B cell maturation and the production of antibodies. A lack of this type of immune response leads to recurrent respiratory tract infections in people with this disorder. It is unclear how DOCK8 gene mutations are involved in other features of AR-HIES, such as the elevation of IgE levels, autoimmunity, and neurological problems.  Some people with AR-HIES do not have mutations in the DOCK8 gene. The genetic cause of the condition in these individuals is unknown.
Is autosomal recessive hyper-IgE 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.
What are the treatments for autosomal recessive hyper-IgE syndrome ? 

These resources address the diagnosis or management of autosomal recessive hyper-IgE syndrome:  - Genetic Testing Registry: Hyperimmunoglobulin E syndrome  - MedlinePlus Encyclopedia: Hyperimmunoglobulin E Syndrome  - Merck Manual Professional Version: Hyperimmunoglobulin E Syndrome  - PID UK: Hyperimmunoglobulin E Syndromes Treatment and Immunizations   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
What is (are) infantile neuronal ceroid lipofuscinosis ? 

Infantile neuronal ceroid lipofuscinosis (NCL) is an inherited disorder that primarily affects the nervous system. Beginning in infancy, children with this condition have intellectual and motor disability, rarely developing the ability to speak or walk. Affected children often have muscle twitches (myoclonus), recurrent seizures (epilepsy), or vision impairment. An unusually small head (microcephaly) and progressive loss of nerve cells in the brain are also characteristic features of this disorder. Children with infantile NCL usually do not survive past childhood.  Infantile NCL is one of a group of NCLs (collectively called Batten disease) that affect the nervous system and typically cause progressive problems with vision, movement, and thinking ability. The different types of NCLs are distinguished by the age at which signs and symptoms first appear.
How many people are affected by infantile neuronal ceroid lipofuscinosis ? 

The incidence of infantile NCL is unknown. Collectively, all forms of NCL affect an estimated 1 in 100,000 individuals worldwide. NCLs are more common in Finland, where approximately 1 in 12,500 individuals are affected.
What are the genetic changes related to infantile neuronal ceroid lipofuscinosis ? 

Mutations in the PPT1 gene cause most cases of infantile NCL. The PPT1 gene provides instructions for making an enzyme called palmitoyl-protein thioesterase 1. This enzyme is active in cell compartments called lysosomes, which digest and recycle different types of molecules. Palmitoyl-protein thioesterase 1 removes certain fats called long-chain fatty acids from proteins, which probably helps break down the proteins. Palmitoyl-protein thioesterase 1 is also thought to be involved in a variety of other cell functions.  PPT1 gene mutations that cause infantile NCL decrease the production or function of palmitoyl-protein thioesterase 1. A shortage of functional enzyme impairs the removal of fatty acids from proteins. In the lysosomes, these fats and proteins accumulate as fatty substances called lipopigments. These accumulations occur in cells throughout the body, but nerve cells in the brain seem to be particularly vulnerable to the damage caused by buildup of lipopigments and the loss of enzyme function. The progressive death of cells, especially in the brain, leads to the signs and symptoms of infantile NCL.
Is infantile neuronal ceroid lipofuscinosis 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.
What are the treatments for infantile neuronal ceroid lipofuscinosis ? 

These resources address the diagnosis or management of infantile neuronal ceroid lipofuscinosis:  - Genetic Testing Registry: Ceroid lipofuscinosis neuronal 1  - Genetic Testing Registry: Infantile neuronal ceroid lipofuscinosis   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
What is (are) Crigler-Najjar syndrome ? 

Crigler-Najjar syndrome is a severe condition characterized by high levels of a toxic substance called bilirubin in the blood (hyperbilirubinemia). Bilirubin is produced when red blood cells are broken down. This substance is removed from the body only after it undergoes a chemical reaction in the liver, which converts the toxic form of bilirubin (called unconjugated bilirubin) to a nontoxic form called conjugated bilirubin. People with Crigler-Najjar syndrome have a buildup of unconjugated bilirubin in their blood (unconjugated hyperbilirubinemia).  Bilirubin has an orange-yellow tint, and hyperbilirubinemia causes yellowing of the skin and whites of the eyes (jaundice). In Crigler-Najjar syndrome, jaundice is apparent at birth or in infancy. Severe unconjugated hyperbilirubinemia can lead to a condition called kernicterus, which is a form of brain damage caused by the accumulation of unconjugated bilirubin in the brain and nerve tissues. Babies with kernicterus are often extremely tired (lethargic) and may have weak muscle tone (hypotonia). These babies may experience episodes of increased muscle tone (hypertonia) and arching of their backs. Kernicterus can lead to other neurological problems, including involuntary writhing movements of the body (choreoathetosis), hearing problems, or intellectual disability.  Crigler-Najjar syndrome is divided into two types. Type 1 (CN1) is very severe, and affected individuals can die in childhood due to kernicterus, although with proper treatment, they may survive longer. Type 2 (CN2) is less severe. People with CN2 are less likely to develop kernicterus, and most affected individuals survive into adulthood.
How many people are affected by Crigler-Najjar syndrome ? 

Crigler-Najjar syndrome is estimated to affect fewer than 1 in 1 million newborns worldwide.
What are the genetic changes related to Crigler-Najjar syndrome ? 

Mutations in the UGT1A1 gene cause Crigler-Najjar syndrome. This gene provides instructions for making the bilirubin uridine diphosphate glucuronosyl transferase (bilirubin-UGT) enzyme, which is found primarily in liver cells and is necessary for the removal of bilirubin from the body.  The bilirubin-UGT enzyme performs a chemical reaction called glucuronidation. During this reaction, the enzyme transfers a compound called glucuronic acid to unconjugated bilirubin, converting it to conjugated bilirubin. Glucuronidation makes bilirubin dissolvable in water so that it can be removed from the body.  Mutations in the UGT1A1 gene that cause Crigler-Najjar syndrome result in reduced or absent function of the bilirubin-UGT enzyme. People with CN1 have no enzyme function, while people with CN2 have less than 20 percent of normal function. The loss of bilirubin-UGT function decreases glucuronidation of unconjugated bilirubin. This toxic substance then builds up in the body, causing unconjugated hyperbilirubinemia and jaundice.
Is Crigler-Najjar syndrome inherited ? 

Crigler-Najjar syndrome is inherited in an autosomal recessive pattern, which means both copies of the UGT1A1 gene in each cell have mutations. A less severe condition called Gilbert syndrome can occur when one copy of the UGT1A1 gene has a mutation.
What are the treatments for Crigler-Najjar syndrome ? 

These resources address the diagnosis or management of Crigler-Najjar syndrome:  - Centers for Disease Control and Prevention: Facts About Jaundice and Kernicterus  - Genetic Testing Registry: Crigler Najjar syndrome, type 1  - Genetic Testing Registry: Crigler-Najjar syndrome  - Genetic Testing Registry: Crigler-Najjar syndrome, type II   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