bowang0911/MedQuAD huggingface dataset:
Limb-girdle muscular dystrophy is a term for a group of diseases that cause weakness and wasting of the muscles in the arms and legs. The muscles most affected are those closest to the body (proximal muscles), specifically the muscles of the shoulders, upper arms, pelvic area, and thighs.  The severity, age of onset, and features of limb-girdle muscle dystrophy vary among the many subtypes of this condition and may be inconsistent even within the same family. Signs and symptoms may first appear at any age and generally worsen with time, although in some cases they remain mild.  In the early stages of limb-girdle muscular dystrophy, affected individuals may have an unusual walking gait, such as waddling or walking on the balls of their feet, and may also have difficulty running. They may need to use their arms to press themselves up from a squatting position because of their weak thigh muscles. As the condition progresses, people with limb-girdle muscular dystrophy may eventually require wheelchair assistance.  Muscle wasting may cause changes in posture or in the appearance of the shoulder, back, and arm. In particular, weak shoulder muscles tend to make the shoulder blades (scapulae) "stick out" from the back, a sign known as scapular winging. Affected individuals may also have an abnormally curved lower back (lordosis) or a spine that curves to the side (scoliosis). Some develop joint stiffness (contractures) that can restrict movement in their hips, knees, ankles, or elbows. Overgrowth (hypertrophy) of the calf muscles occurs in some people with limb-girdle muscular dystrophy.  Weakening of the heart muscle (cardiomyopathy) occurs in some forms of limb-girdle muscular dystrophy. Some affected individuals experience mild to severe breathing problems related to the weakness of muscles needed for breathing.  Intelligence is generally unaffected in limb-girdle muscular dystrophy; however, developmental delay and intellectual disability have been reported in rare forms of the disorder.
The various forms of limb-girdle muscular dystrophy are caused by mutations in many different genes. These genes provide instructions for making proteins that are involved in muscle maintenance and repair.  Some of the proteins produced from these genes assemble with other proteins into larger protein complexes. These complexes maintain the physical integrity of muscle tissue and allow the muscles to contract. Other proteins participate in cell signaling, cell membrane repair, or the removal of potentially toxic wastes from muscle cells.  Limb-girdle muscular dystrophy is classified based on its inheritance pattern and genetic cause. Limb-girdle muscular dystrophy type 1 includes forms of the disorder that have an inheritance pattern called autosomal dominant. Mutations in the LMNA gene cause limb-girdle muscular dystrophy type 1B. Limb-girdle muscular dystrophy type 1C is one of a group of muscle disorders called caveolinopathies caused by mutations in the CAV3 gene.  Limb-girdle muscular dystrophy type 2 includes forms of the disorder that have an inheritance pattern called autosomal recessive. Calpainopathy, or limb-girdle muscular dystrophy type 2A, is caused by mutations in the CAPN3 gene. Type 2A is the most common form of limb-girdle muscular dystrophy, accounting for about 30 percent of cases. Dysferlinopathy, also called limb-girdle muscular dystrophy type 2B, is caused by mutations in the DYSF gene.  Sarcoglycanopathies are forms of limb-girdle muscular dystrophy caused by mutations in the SGCA, SGCB, SGCG, and SGCD genes. These sarcoglycanopathies are known as limb-girdle muscular dystrophy types 2D, 2E, 2C, and 2F respectively.  A TTN gene mutation causes limb-girdle muscular dystrophy type 2J, which has been identified only in the Finnish population. Mutations in the ANO5 gene cause limb-girdle muscular dystrophy type 2L. Mutations in several other genes cause forms of limb-girdle muscular dystrophy called dystroglycanopathies, including limb-girdle muscular dystrophy types 2I, 2K, 2M, and 2N.  Other rare forms of limb-girdle muscular dystrophy are caused by mutations in several other genes, some of which have not been identified.
Limb-girdle muscular dystrophy can have different inheritance patterns.  Most forms of this condition are 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.  Several rare forms of limb-girdle muscular dystrophy are inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder.
These resources address the diagnosis or management of limb-girdle muscular dystrophy:  - Cleveland Clinic  - Gene Review: Gene Review: Limb-Girdle Muscular Dystrophy Overview  - Genetic Testing Registry: Limb-girdle muscular dystrophy  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 1A  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 1B  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 1C  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 1E  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 1F  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 1G  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 1H  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 2A  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 2B  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 2D  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 2E  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 2F  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 2G  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 2J  - Genetic Testing Registry: Limb-girdle muscular dystrophy, type 2L  - Genetic Testing Registry: Limb-girdle muscular dystrophy-dystroglycanopathy, type C1  - Genetic Testing Registry: Limb-girdle muscular dystrophy-dystroglycanopathy, type C2  - Genetic Testing Registry: Limb-girdle muscular dystrophy-dystroglycanopathy, type C3  - Genetic Testing Registry: Limb-girdle muscular dystrophy-dystroglycanopathy, type C4  - Genetic Testing Registry: Limb-girdle muscular dystrophy-dystroglycanopathy, type C5  - Johns Hopkins Medicine  - LGMD-Diagnosis.org   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
Pitt-Hopkins syndrome is a condition characterized by intellectual disability and developmental delay, breathing problems, recurrent seizures (epilepsy), and distinctive facial features.  People with Pitt-Hopkins syndrome have moderate to severe intellectual disability. Most affected individuals have delayed development of mental and motor skills (psychomotor delay). They are delayed in learning to walk and developing fine motor skills such as picking up small items with their fingers. People with Pitt-Hopkins syndrome typically do not develop speech; some may learn to say a few words. Many affected individuals exhibit features of autistic spectrum disorders, which are characterized by impaired communication and socialization skills.  Breathing problems in individuals with Pitt-Hopkins syndrome are characterized by episodes of rapid breathing (hyperventilation) followed by periods in which breathing slows or stops (apnea). These episodes can cause a lack of oxygen in the blood, leading to a bluish appearance of the skin or lips (cyanosis). In some cases, the lack of oxygen can cause loss of consciousness. Some older individuals with Pitt-Hopkins syndrome develop widened and rounded tips of the fingers and toes (clubbing) because of recurrent episodes of decreased oxygen in the blood. The breathing problems occur only when the person is awake and typically first appear in mid-childhood, but they can begin as early as infancy. Episodes of hyperventilation and apnea can be triggered by emotions such as excitement or anxiety or by extreme tiredness (fatigue).  Epilepsy occurs in most people with Pitt-Hopkins syndrome and usually begins during childhood, although it can be present from birth.  Individuals with Pitt-Hopkins syndrome have distinctive facial features that include thin eyebrows, sunken eyes, a prominent nose with a high nasal bridge, a pronounced double curve of the upper lip (Cupid's bow), a wide mouth with full lips, and widely spaced teeth. The ears are usually thick and cup-shaped.  Children with Pitt-Hopkins syndrome typically have a happy, excitable demeanor with frequent smiling, laughter, and hand-flapping movements. However, they can also experience anxiety and behavioral problems.  Other features of Pitt-Hopkins syndrome may include constipation and other gastrointestinal problems, an unusually small head (microcephaly), nearsightedness (myopia), eyes that do not look in the same direction (strabismus), short stature, and minor brain abnormalities. Affected individuals may also have small hands and feet, a single crease across the palms of the hands, flat feet (pes planus), or unusually fleshy pads at the tips of the fingers and toes. Males with Pitt-Hopkins syndrome may have undescended testes (cryptorchidism).
Mutations in the TCF4 gene cause Pitt-Hopkins syndrome. This gene provides instructions for making a protein that attaches (binds) to other proteins and then binds to specific regions of DNA to help control the activity of many other genes. On the basis of its DNA binding and gene controlling activities, the TCF4 protein is known as a transcription factor. The TCF4 protein plays a role in the maturation of cells to carry out specific functions (cell differentiation) and the self-destruction of cells (apoptosis).  TCF4 gene mutations disrupt the protein's ability to bind to DNA and control the activity of certain genes. These disruptions, particularly the inability of the TCF4 protein to control the activity of genes involved in nervous system development and function, contribute to the signs and symptoms of Pitt-Hopkins syndrome. Furthermore, additional proteins interact with the TCF4 protein to carry out specific functions. When the TCF4 protein is nonfunctional, these other proteins are also unable to function normally. It is also likely that the loss of the normal proteins that are attached to the nonfunctional TCF4 proteins contribute to the features of this condition. The loss of one protein in particular, the ASCL1 protein, is thought to be associated with breathing problems in people with Pitt-Hopkins syndrome.
CHOPS syndrome is a disorder involving multiple abnormalities that are present from birth (congenital). The name "CHOPS" is an abbreviation for a list of features of the disorder including cognitive impairment, coarse facial features, heart defects, obesity, lung (pulmonary) involvement, short stature, and skeletal abnormalities.  Children with CHOPS syndrome have intellectual disability and delayed development of skills such as sitting and walking. Characteristic facial features include a round face; thick hair; thick eyebrows that grow together in the middle (synophrys); wide-set, bulging eyes with long eyelashes; a short nose; and down-turned corners of the mouth.  Most affected individuals are born with a heart defect called patent ductus arteriosus (PDA). The ductus arteriosus is a connection between two major arteries, the aorta and the pulmonary artery. This connection is open during fetal development and normally closes shortly after birth. However, the ductus arteriosus remains open, or patent, in babies with PDA. If untreated, this heart defect causes infants to breathe rapidly, feed poorly, and gain weight slowly; in severe cases, it can lead to heart failure. Multiple heart abnormalities have sometimes been found in children with CHOPS syndrome. In addition to PDA, affected individuals may have ventricular septal defect, which is a defect in the muscular wall (septum) that separates the right and left sides of the heart's lower chamber.  People with CHOPS syndrome have abnormalities of the throat and airways that cause momentary cessation of breathing while asleep (obstructive sleep apnea). These abnormalities can also cause affected individuals to breathe food or fluids into the lungs accidentally, which can lead to a potentially life-threatening bacterial lung infection (aspiration pneumonia) and chronic lung disease. Affected individuals are shorter than more than 97 percent of their peers and are overweight for their height. They also have skeletal differences including unusually short fingers and toes (brachydactyly) and abnormally-shaped spinal bones (vertebrae).  Other features that can occur in CHOPS syndrome include a small head size (microcephaly); hearing loss; clouding of the lens of the eye (cataract); a single, horseshoe-shaped kidney; and, in affected males, undescended testes (cryptorchidism).
CHOPS syndrome is caused by mutations in the AFF4 gene. This gene provides instructions for making part of a protein complex called the super elongation complex (SEC). During embryonic development, the SEC is involved in an activity called transcription, which is the first step in the production of proteins from genes. By re-starting the transcription of certain genes after pauses that normally occur during the process, the SEC helps ensure that development proceeds appropriately before birth.  Mutations in the AFF4 gene are thought to result in an AFF4 protein that is not broken down when it is no longer needed, so more AFF4 protein is available than usual. The excess AFF4 protein interferes with normal pauses in transcription. This dysregulation of transcription leads to problems in the development of multiple organs and tissues, resulting in the signs and symptoms of CHOPS syndrome.
Netherton syndrome is a disorder that affects the skin, hair, and immune system. Newborns with Netherton syndrome have skin that is red and scaly (ichthyosiform erythroderma), and the skin may leak fluid. Some affected infants are born with a tight, clear sheath covering their skin called a collodion membrane. This membrane is usually shed during the first few weeks of life. Because newborns with this disorder are missing the protection provided by normal skin, they are at risk of becoming dehydrated and developing infections in the skin or throughout the body (sepsis), which can be life-threatening. Affected babies may also fail to grow and gain weight at the expected rate (failure to thrive). The health of older children and adults with Netherton syndrome usually improves, although they often remain underweight and of short stature.  After infancy, the severity of the skin abnormalities varies among people with Netherton syndrome and can fluctuate over time. The skin may continue to be red and scaly, especially during the first few years of life. Some affected individuals have intermittent redness or experience outbreaks of a distinctive skin abnormality called ichthyosis linearis circumflexa, involving patches of multiple ring-like lesions. The triggers for the outbreaks are not known, but researchers suggest that stress or infections may be involved.  Itchiness is a common problem for affected individuals, and scratching can lead to frequent infections. Dead skin cells are shed at an abnormal rate and often accumulate in the ear canals, which can affect hearing if not removed regularly. The skin is abnormally absorbent of substances such as lotions and ointments, which can result in excessive blood levels of some topical medications. Because the ability of the skin to protect against heat and cold is impaired, affected individuals may have difficulty regulating their body temperature.  People with Netherton syndrome have hair that is fragile and breaks easily. Some strands of hair vary in diameter, with thicker and thinner spots. This feature is known as bamboo hair, trichorrhexis nodosa, or trichorrhexis invaginata. In addition to the hair on the scalp, the eyelashes and eyebrows may be affected. The hair abnormality in Netherton syndrome may not be noticed in infancy because babies often have sparse hair.  Most people with Netherton syndrome have immune system-related problems such as food allergies, hay fever, asthma, or an inflammatory skin disorder called eczema.
Netherton syndrome is caused by mutations in the SPINK5 gene. This gene provides instructions for making a protein called LEKT1. LEKT1 is a type of serine peptidase inhibitor. Serine peptidase inhibitors control the activity of enzymes called serine peptidases, which break down other proteins. LEKT1 is found in the skin and in the thymus, which is a gland located behind the breastbone that plays an important role in the immune system by producing white blood cells called lymphocytes. LEKT1 controls the activity of certain serine peptidases in the outer layer of skin (the epidermis), especially the tough outer surface known as the stratum corneum, which provides a sturdy barrier between the body and its environment. Serine peptidase enzymes are involved in normal skin shedding by helping to break the connections between cells of the stratum corneum. LEKT1 is also involved in normal hair growth, the development of lymphocytes in the thymus, and the control of peptidases that trigger immune system function.  Mutations in the SPINK5 gene result in a LEKT1 protein that is unable to control serine peptidase activity. The lack of LEKT1 function allows the serine peptidases to be abnormally active and break down too many proteins in the stratum corneum. As a result, too much skin shedding takes place, and the stratum corneum is too thin and breaks down easily, resulting in the skin abnormalities that occur in Netherton syndrome. Loss of LEKT1 function also results in abnormal hair growth and immune dysfunction that leads to allergies, asthma, and eczema.
Kabuki syndrome is a disorder that affects many parts of the body. It is characterized by distinctive facial features including arched eyebrows; long eyelashes; long openings of the eyelids (long palpebral fissures) with the lower lids turned out (everted) at the outside edges; a flat, broadened tip of the nose; and large protruding earlobes. The name of this disorder comes from the resemblance of its characteristic facial appearance to stage makeup used in traditional Japanese theater called Kabuki.  People with Kabuki syndrome have developmental delay and intellectual disability that range from mild to severe. Affected individuals may also have seizures, an unusually small head size (microcephaly), or weak muscle tone (hypotonia). Some have eye problems such as rapid, involuntary eye movements (nystagmus) or eyes that do not look in the same direction (strabismus).  Other characteristic features of Kabuki syndrome include short stature and skeletal abnormalities such as abnormal side-to-side curvature of the spine (scoliosis), short fifth fingers, or problems with the hip and knee joints. The roof of the mouth may have an abnormal opening (cleft palate) or be high and arched, and dental problems are common in affected individuals. People with Kabuki syndrome may also have fingerprints with unusual features and fleshy pads at the tips of the fingers. These prominent finger pads are called fetal finger pads because they normally occur in human fetuses; in most people they disappear before birth.  A wide variety of other health problems occur in some people with Kabuki syndrome. Among the most commonly reported are heart abnormalities, frequent ear infections (otitis media), hearing loss, and early puberty.
Kabuki syndrome is caused by mutations in the KMT2D gene (also known as MLL2) or the KDM6A gene.  Between 55 and 80 percent of cases of Kabuki syndrome are caused by mutations in the KMT2D gene. This gene provides instructions for making an enzyme called lysine-specific methyltransferase 2D that is found in many organs and tissues of the body. Lysine-specific methyltransferase 2D functions as a histone methyltransferase. Histone methyltransferases are enzymes that modify proteins called histones. Histones are structural proteins that attach (bind) to DNA and give chromosomes their shape. By adding a molecule called a methyl group to histones (a process called methylation), histone methyltransferases control (regulate) the activity of certain genes. Lysine-specific methyltransferase 2D appears to activate certain genes that are important for development.  About 6 percent of cases of Kabuki syndrome are caused by mutations in the KDM6A gene. This gene provides instructions for making an enzyme called lysine-specific demethylase 6A. This enzyme is a histone demethylase, which means that it helps to remove methyl groups from certain histones. Like lysine-specific methyltransferase 2D, lysine-specific demethylase 6A regulates the activity of certain genes, and research suggests that the two enzymes work together to control certain developmental processes.  The KMT2D and KDM6A gene mutations associated with Kabuki syndrome lead to the absence of the corresponding functional enzyme. A lack of the enzymes produced from these genes disrupts normal histone methylation and impairs proper activation of certain genes in many of the body's organs and tissues, resulting in the abnormalities of development and function characteristic of Kabuki syndrome.  Some people with Kabuki syndrome have no identified KMT2D or KDM6A gene mutation. The cause of the disorder in these individuals is unknown.
When Kabuki syndrome is caused by mutations in the KMT2D gene, it is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder.  When Kabuki syndrome is caused by mutations in the KDM6A gene, it is inherited in an X-linked dominant pattern. The KDM6A gene is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a mutation in one of the two copies of the gene in each cell is sufficient to cause the disorder. In males (who have only one X chromosome), a mutation in the only copy of the gene in each cell causes the disorder. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.  Most cases of Kabuki syndrome result from a new mutation in one of these genes and occur in people with no history of the disorder in their family. In a few cases, an affected person is believed to have inherited the mutation from one affected parent.
These resources address the diagnosis or management of Kabuki syndrome:  - Boston Children's Hospital  - Gene Review: Gene Review: Kabuki Syndrome  - Genetic Testing Registry: Kabuki make-up syndrome  - Genetic Testing Registry: Kabuki syndrome 2   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