Adams-Oliver syndrome (AOS) is an extremely rare inherited disorder characterized by defects of the scalp and abnormalities of the fingers, toes, arms, and/or legs. The physical abnormalities associated with this disorder vary greatly among affect...

Seborrheic Keratosis is a skin disorder usually characterized by discolored lesions that appear to be "stuck on" the skin surface. Warts may appear and skin is often oily or greasy. These skin lesions are sometimes mistaken for cancerous growths a...

Fetal retinoid syndrome is a characteristic pattern of mental and physical birth defects that results from maternal use of retinoids, the synthetic derivatives of vitamin A, during pregnancy. The most well known retinoid is isotretinoin (Accutane)...

Osteopetrosis may be inherited as either a dominant or recessive trait and is marked by increased bone density, brittle bones, and, in some cases, skeletal abnormalities. Although symptoms may not initially be apparent in people with mild forms of...

A prolactinoma is a benign tumor of the pituitary gland (adenoma) that produces an excessive amount of the hormone prolactin. In women, hyperprolactinemia is characterized by irregular menstrual periods (amenorrhea), infertility and production of ...

MCT8-specific thyroid hormone cell transporter deficiency (THCT deficiency) is an inherited disorder that is characterized by severe mental retardation, an impaired ability to speak, diminished muscle tone (hypotonia), and/or movement abnormalitie...

MCT8-specific thyroid hormone cell transporter deficiency (THCT deficiency) is an inherited disorder that is characterized by severe mental retardation, an impaired ability to speak, diminished muscle tone (hypotonia), and/or movement abnormalitie...

Aortic stenosis is abnormal narrowing of the aortic valve. A number of conditions cause disease resulting in narrowing of the aortic valve. When the degree of narrowing becomes significant enough to impede the flow of blood from the left ventricle...

Apert syndrome, also known as acrocephalosyndactyly type I (ACS1), is a rare genetic disorder that is apparent at birth (congenital). The disorder is character-ized by distinctive malformations of the head that lead to distinctive facial features....

Aplasia Cutis Congenita is a rare disorder with a complicated pattern of inheritance. Babies are born with the absence of certain layer(s) of skin, most often on the scalp, but also on the trunk, and/or arms and legs. The affected area is typicall...

Jervell and Lange-Nielsen syndrome (JLNS) is a rare inherited disorder characterized by deafness present at birth (congenital) occurring in association with abnormalities affecting the electrical system of the heart. The severity of cardiac sympto...

Froehlich syndrome is a constellation of endocrine abnormalities believed to result from damage to the hypothalamus, a part of the brain where certain functions such as sleep cycles and body temperature are regulated. Froehlich syndrome appears to...

Bacterial vaginosis is an abnormal vaginal condition that is characterized by vaginal discharge and results from an overgrowth of atypical bacteria in the vagina. Bacterial vaginosis is not dangerous, but it can cause disturbing sym...

Batten disease, a rare genetic disorder, belongs to a group of progressive degenerative neurometabolic disorders known as the neuronal ceroid lipofuscinoses. These disorders share certain similar symptoms and are distinguished in part by the age a...

Batten Turner Type Congenital Myopathy is an extremely rare, inherited muscle disease (myopathy) and is characterized by the lack of muscle tone or floppiness at birth (congenital hypotonia). The symptoms of Batten Turner Type Congenital Myopathy ...

Batten disease, a rare genetic disorder, belongs to a group of progressive degenerative neurometabolic disorders known as the neuronal ceroid lipofuscinoses. These disorders share certain similar symptoms and are distinguished in part by the age a...

Beckwith-Wiedemann syndrome (BWS) is a rare genetic overgrowth disorder. It is characterized by a wide spectrum of symptoms and physical findings that vary in range and severity from case to case. However, in many individuals, associated features ...

Hairy tongue is an uncommon, benign condition that is also known as black hairy tongue or lingua nigra. It is characterized by abnormal elongation and blackish or dark brownish discoloration or "staining" of the thread-like elevations (filiform pa...

Blue rubber bleb nevus syndrome (BRBNS) is a rare blood vessel (vascular) disorder that affects the skin and internal organs of the body. Multiple distinctive skin lesions are usually characteristic of this disorder and are often present at birth ...

Turner syndrome is a rare chromosomal disorder that affects females. The disorder is characterized by partial or complete loss (monosomy) of one of the X chromosomes. Turner syndrome is highly variable and can differ dramatically from one person t...

Bowen Hutterite syndrome is a rare genetic disorder that is apparent at birth (congenital). The disorder is characterized by growth delays before birth (intrauterine growth retardation); failure to grow and gain weight at the expected rate (failur...

Bowen Hutterite syndrome is a rare genetic disorder that is apparent at birth (congenital). The disorder is characterized by growth delays before birth (intrauterine growth retardation); failure to grow and gain weight at the expected rate (failur...

Cornelia de Lange syndrome (CdLS) is a rare genetic disorder that is apparent at birth (congenital). Associated symptoms and findings typically include delays in physical development before and after birth (prenatal and postnatal growth retardatio...

Maple syrup urine disease (MSUD) is a rare genetic disorder characterized by deficiency of certain enzymes (branched-chain alpha-keto acid dehydrogenase complex) required to breakdown (metabolize) specific amino acids in the body. Because these am...

Branchio-oto-renal (BOR) syndrome is a rare disorder inherited as an autosomal dominant genetic trait. This disorder is characterized by pits or ear tags in front of the outer ear, abnormal passages from the throat to the outside surface of the ne...

Branchio-oculo-facial syndrome (BOFS) is a very rare genetic disorder that is apparent at birth (congenital). As of 2004, only about 50 cases of BOFS had been reported in the medical literature. The symptoms of most BOFS patients include the proli...

Acrodermatitis enteropathica (AE) is a disorder of zinc metabolism that occurs in one of two forms: an inborn (congenital) form and an acquired form. The inborn form of AE is a rare genetic disorder characterized by intestinal abnormalities that l...

Campomelic dysplasia is a severe disorder that affects the development of the skeleton and reproductive system. This condition is often life-threatening in the newborn period. The term "campomelic" comes from the Greek words for "bent limb." Affec...

Campomelic syndrome is a rare congenital disorder in which multiple anomalies are present. It is characterized by bowing and angular shape of the long bones of the legs, especially the tibia; multiple minor anomalies of the face; cleft palate; oth...

Camptomelic syndrome is a rare congenital disorder in which multiple anomalies are present. It is characterized by bowing and angular shape of the long bones of the legs, especially the tibia; multiple minor anomalies of the face; cleft palate; ot...

Camurati-Engelmann disease is a rare genetic disorder characterized by progressive widening and malformation of the shafts of the long bones (diaphyseal dysplasia). Major symptoms may include bone pain, particularly in the legs; skeletal abnormali...

General DiscussionPentalogy of Cantrell is a rare disorder that is present at birth (congenital). Pentalogy of Cantrell is characterized by a combination of birth defects. These birth defects can potentially involve the breastbone (sternu...

Celiac disease, sometimes called celiac sprue or gluten-sensitive enteropathy, i...

Cerebral palsy facts Cerebral palsy (CP) is an abnormality of motor function, the ability to move and control movements. Cerebral palsy is acquired at an early age, usually less than a year of age. Cerebral palsy...

What is the cervix? The cervix is part of a woman's reproductive system. It's in the pelvis. The cervix is the lower, narrow part of the uterus (womb). The cervix is a passageway: The cervix connects the uterus to th...

Chanarin Dorfman syndrome is a rare hereditary disorder of fat (lipid) metabolism. It is characterized by scaly skin (ichthyosis), degeneration of the muscles (myopathy), and abnormal white blood cells with small spaces (vacuoles) filled with fat ...

Chlamydia is a common sexually transmitted infection (STI) caused by the bacterium Chlamydia trachomatis. It can be transmitted through unprotected sexual contact with an infected person. Chlamydia can infect both men and women and can cause sympt...

Cerebro-oculo-facio-skeletal (COFS) syndrome is a genetic degenerative disorder of the brain and spinal cord that begins before birth. The disorder is characterized by growth failure at birth and little or no neurological development, structural a...

Walker-Warburg syndrome (WWS) is a rare multisystem disorder characterized by muscle, brain and eye abnormalities, often leading to death in the first weeks of life. However, the specific symptoms and severity of WWS can vary greatly from case to ...

Coffin-Lowry syndrome is a rare genetic disorder characterized by mental retardation; abnormalities of the head and facial (craniofacial) area; large, soft hands with short, thin (tapered) fingers; short stature; and/or various skeletal abnormalit...

Coffin-Siris syndrome is a rare genetic disorder that may be evident at birth (congenital). The disorder may be characterized by feeding difficulties and frequent respiratory infections during infancy, diminished muscle tone (hypotonia), abnormal ...

Coffin-Lowry syndrome is a rare genetic disorder characterized by mental retardation; abnormalities of the head and facial (craniofacial) area; large, soft hands with short, thin (tapered) fingers; short stature; and/or various skeletal abnormalit...

Cerebro-oculo-facio-skeletal (COFS) syndrome is a genetic degenerative disorder of the brain and spinal cord that begins before birth. The disorder is characterized by growth failure at birth and little or no neurological development, structural a...

Freeman-Sheldon syndrome is a rare inherited disorder characterized by multiple contractures (i.e., restricted movement around two or more body areas) at birth (congenital), abnormalities of the head and face (craniofacial) area, defects of the ha...

Chromosome 22q11.2 deletion syndrome is associated with a range of problems including: congenital heart disease, palate abnormalities, immune system dysfunction including autoimmune disease, low calcium (hypocalcemia) and other endocrine abnormali...

Craniofrontonasal dysplasia is a very rare inherited disorder characterized by abnormalities of the head and face (craniofacial area), hands and feet, and certain skeletal bones. Major symptoms of this disorder may include widely spaced eyes (ocul...

Craniofrontonasal dysplasia is a very rare inherited disorder characterized by abnormalities of the head and face (craniofacial area), hands and feet, and certain skeletal bones. Major symptoms of this disorder may include widely spaced eyes (ocul...

Crouzon syndrome is a rare genetic disorder that may be evident at birth (congenital) or during infancy. The disorder is characterized by distinctive malformations of the skull and facial (craniofacial) region. Such abnormalities may vary greatly ...

Crouzon syndrome is a rare genetic disorder that may be evident at birth (congenital) or during infancy. The disorder is characterized by distinctive malformations of the skull and facial (craniofacial) region. Such abnormalities may vary greatly ...

Fraser syndrome is a rare genetic disorder characterized by partial webbing of the fingers and/or toes (partial syndactyly), kidney (renal) abnormalities, genital malformations, and/or, in some cases, complete fusion of the eyelids (cryptophthalmo...

De Barsy syndrome is a rare, autosomal recessive genetic disorder, the main characteristics of which are a prematurely aged-looking face (progeria), cloudy corneas, short stature, and mental retardation. The condition is expressed in variable pres...

De Barsy syndrome is a rare, autosomal recessive genetic disorder, the main characteristics of which are a prematurely aged-looking face (progeria), cloudy corneas, short stature, and mental retardation. The condition is expressed in variable pres...

Cornelia de Lange syndrome (CdLS) is a rare genetic disorder that is apparent at birth (congenital). Associated symptoms and findings typically include delays in physical development before and after birth (prenatal and postnatal growth retardatio...

De Sanctis-Cacchione syndrome is an extremely rare disorder characterized by the skin and eye symptoms of xeroderma pigmentosum (XP) occurring in association with neurological abnormalities, mental retardation, unusually short stature (dwarfism), ...

Peeling skin syndrome is a rare inherited skin disorder characterized by painless, continual, spontaneous skin peeling (exfoliation). Other findings may include blistering and/or reddening of the skin (erythema) and itching (pruritus). Peeling ski...

Hereditary multiple osteochondromas (HMO) is a rare genetic disorder characterized by multiple benign (noncancerous) bone tumors that are covered by cartilage (osteochondromas), often on the growing end (metaphysis) of the long bones of the legs, ...

Camurati-Engelmann disease is a rare genetic disorder characterized by progressive widening and malformation of the shafts of the long bones (diaphyseal dysplasia). Major symptoms may include bone pain, particularly in the legs; skeletal abnormali...

Diastrophic dysplasia, which is also known as disastrophic dwarfism, is a rare disorder that is present at birth (congenital). The range and severity of associated symptoms and physical findings may vary greatly from case to case. However, the dis...

Diastrophic dysplasia, which is also known as disastrophic dwarfism, is a rare disorder that is present at birth (congenital). The range and severity of associated symptoms and physical findings may vary greatly from case to case. However, the dis...

The diencephalic syndrome is a very rare neurological disorder characterized by failure to thrive, abnormal thinness (emaciation), amnesia, intense sleepiness, unusual eye position and sometimes blindness. It is normally seen in infancy or early c...

The diencephalic syndrome is a very rare neurological disorder characterized by failure to thrive, abnormal thinness (emaciation), amnesia, intense sleepiness, unusual eye position and sometimes blindness. It is normally seen in infancy or early c...

Dyggve-Melchior-Clausen (DMC) syndrome is a rare, progressive genetic disorder characterized by abnormal skeletal development, microcephaly and intellectual disability. The condition was first reported by Dyggve, Melchior and Clausen in 1962 in th...

Dyggve-Melchior-Clausen (DMC) syndrome is a rare, progressive genetic disorder characterized by abnormal skeletal development, microcephaly and intellectual disability. The condition was first reported by Dyggve, Melchior and Clausen in 1962 in th...

Sjogren-Larsson syndrome is an inherited disorder characterized by scaling skin (ichthyosis), mental retardation, speech abnormalities, and spasticity. Affected infants develop various degrees of reddened skin with fine scales soon after birth. Af...

Down syndrome is a genetic disorder and the most common autosomal chromosome abnormality in humans, where extra genetic material from chromosome 21 is transferred to a newly formed embryo. These extra genes and DNA cause changes in the development...

Dubowitz syndrome is a very rare genetic and developmental disorder involving multiple congenital (inherited) anomalies including but not limited to: (1) growth failure/short stature; (2) unusual but characteristic facial features; (3) a small hea...

Trisomy 5p is a rare chromosomal disorder in which all or a portion of the short arm (p) of chromosome 5 (5p) appears three times (trisomy) rather than twice in cells of the body. Often the duplicated portion of 5p (trisomy) is due to a complex re...

Chromosome 9, Trisomy 9p is a rare chromosomal syndrome in which a portion of the 9th chromosome appears three times (trisomy) rather than twice in cells of the body. The trisomy may involve a portion of the short arm (9p), the entire short arm, o...

Dyskeratosis congenita is a rare genetic form of bone marrow failure, the inability of the marrow to produce sufficient blood cells. Dyskeratosis is Latin and means the irreversible degeneration of skin tissue, and congenita means inborn. First de...

Dyskeratosis congenita is a rare genetic form of bone marrow failure, the inability of the marrow to produce sufficient blood cells. Dyskeratosis is Latin and means the irreversible degeneration of skin tissue, and congenita means inborn. First de...

Dyskeratosis congenita is a rare genetic form of bone marrow failure, the inability of the marrow to produce sufficient blood cells. Dyskeratosis is Latin and means the irreversible degeneration of skin tissue, and congenita means inborn. First de...

Dyskeratosis congenita is a rare genetic form of bone marrow failure, the inability of the marrow to produce sufficient blood cells. Dyskeratosis is Latin and means the irreversible degeneration of skin tissue, and congenita means inborn. First de...

Alexander disease is named after the physician who first described the condition in 1949 (WS Alexander). It is an extremely rare, usually progressive and fatal, neurological disorder. Initially it was detected most often during infancy or early ch...

Johanson-Blizzard syndrome (JBS) is an extremely rare genetic disorder that affects multiple organ systems of the body. Many symptoms are present at birth (congenital) or early childhood. The spectrum of potential features and physical findings as...

Ectrodactyly ectodermal dysplasia cleft lip/palate (EEC) syndrome is a rare genetic disorder. Symptoms can vary greatly from one person to another. Affected individuals often have abnormalities affecting the limbs including ectrodactyly, a conditi...

Ollier disease is a rare skeletal disorder characterized by abnormal bone development (skeletal dysplasia). While this disorder may be present at birth (congenital); it may not become apparent until early childhood when symptoms, such as deformiti...

Atrioventricular septal defect (ASVD) is a general term for a group of rare heart defects that are present at birth (congenital). Infants with ASVDs have improperly developed atrial and ventricular septa and adjoining valves. The norma...

Endocardial fibroelastosis (EFE) is a rare heart disorder that affects infants and children. It is characterized by a thickening within the muscular lining of the heart chambers due to an increase in the amount of supporting connective tissue (ine...

Epidermal nevus syndromes (ENSs) are a group of rare complex disorders characterized by the presence of skin lesions known as epidermal nevi associated with additional extra-cutaneous abnormalities, most often affecting the brain, eye and skeletal...

Epidermolysis bullosa (EB) is a genetic skin disorder characterized clinically by blister formation from mechanical trauma. There are four main types with additional sub-types identified. There is a spectrum of severity, and within each type, one ...

Tuberous sclerosis is a rare genetic multisystem disorder that is typically apparent shortly after birth. The disorder may be characterized by episodes of uncontrolled electrical activity in the brain (seizures); mental retardation; distinctive sk...

The hereditary ataxias are a group of neurological disorders (ataxias) of varying degrees of rarity that are inherited, in contrast to a related group of neurological disorders that are acquired through accidents, injuries, or other external agent...

Erythema multiforme (EM) is the name applied to a group of hypersensitivity disorders, affecting mostly children and young adults, and characterized by symmetric red, patchy lesions, primarily on the arms and legs. The cause is unknown, but EM fre...

Multiple pterygium syndrome is a very rare genetic disorder characterized by minor facial anomalies, short stature, vertebral defects, multiple joints in a fixed position (contractures) and webbing (pterygia) of the neck, inside bend of the elbows...

Hereditary multiple osteochondromas (HMO) is a rare genetic disorder characterized by multiple benign (noncancerous) bone tumors that are covered by cartilage (osteochondromas), often on the growing end (metaphysis) of the long bones of the legs, ...

Cardiofaciocutaneous (CFC) syndrome is one of the RASopathies and is a rare genetic disorder is typically characterized by unusually sparse, brittle, curly hair; large head (macrocephaly); a prominent forehead and abnormal narrowing of the sides o...

Aarskog syndrome is an extremely rare genetic disorder marked by stunted growth that may not become obvious until the child is about three years of age, broad facial abnormalities, musculoskeletal and genital anomalies, and mild intellectual disab...

Aarskog syndrome is an extremely rare genetic disorder marked by stunted growth that may not become obvious until the child is about three years of age, broad facial abnormalities, musculoskeletal and genital anomalies, and mild intellectual disab...

Peeling skin syndrome is a rare inherited skin disorder characterized by painless, continual, spontaneous skin peeling (exfoliation). Other findings may include blistering and/or reddening of the skin (erythema) and itching (pruritus). Peeling ski...

Congenital fiber type disproportion (CFTD) is a rare genetic muscle disease that is usually apparent at birth (congenital myopathy). It belongs to a group of muscle conditions called the congenital myopathies that tend to affect people in a simila...

Coffin-Siris syndrome is a rare genetic disorder that may be evident at birth (congenital). The disorder may be characterized by feeding difficulties and frequent respiratory infections during infancy, diminished muscle tone (hypotonia), abnormal ...

Focal dermal hypoplasia (FDH), also known as Goltz syndrome, is a rare skin disorder that can also affect bone and eye development. If is a type of ectodermal dysplasia, a group of heritable disorders causing the hair, teeth, nails, and glands to ...

Focal dermal hypoplasia (FDH), also known as Goltz syndrome, is a rare skin disorder that can also affect bone and eye development. If is a type of ectodermal dysplasia, a group of heritable disorders causing the hair, teeth, nails, and glands to ...

Fountain syndrome is an extremely rare inherited disorder that is characterized by mental retardation; abnormal swelling of the cheeks and lips due to the excessive accumulation of body fluids under the skin (subcutaneous) of the face (edema); ske...

Treacher Collins syndrome (TCS) is a rare genetic disorder characterized by distinctive abnormalities of the head and face area resulting from underdevelopment (hypoplasia) of certain facial structures including the jaw, cheekbones and nearby stru...

Hallermann-Streiff syndrome (HSS) is a rare genetic disorder that is primarily characterized by distinctive malformations of the skull and facial (craniofacial) region; sparse hair (hypotrichosis); eye abnormalities; dental defects; degenerative s...

Fraser syndrome is a rare genetic disorder characterized by partial webbing of the fingers and/or toes (partial syndactyly), kidney (renal) abnormalities, genital malformations, and/or, in some cases, complete fusion of the eyelids (cryptophthalmo...

Froehlich syndrome is a constellation of endocrine abnormalities believed to result from damage to the hypothalamus, a part of the brain where certain functions such as sleep cycles and body temperature are regulated. Froehlich syndrome appears to...

Froehlich syndrome is a constellation of endocrine abnormalities believed to result from damage to the hypothalamus, a part of the brain where certain functions such as sleep cycles and body temperature are regulated. Froehlich syndrome appears to...

A very rare syndrome characterized by abnormalities of the bones of the skeleton as well as mental retardation. Various facial, eye and urogenital anomalies are also present....

Fucosidosis is a rare genetic disorder characterized by deficiency of the enzyme alpha-L-fucosidase, which is required to break down (metabolize) certain complex compounds (e.g., fucose-containing glycolipids or fucose-containing glycoproteins). F...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Galloway-Mowat Syndrome, which is also known as Microcephaly-Hiatal Hernia-Nephrotic Syndrome, is an extremely rare genetic disorder that is characterized by a variety of physical and developmental abnormalities. Physical features may include an u...

Galloway-Mowat Syndrome, which is also known as Microcephaly-Hiatal Hernia-Nephrotic Syndrome, is an extremely rare genetic disorder that is characterized by a variety of physical and developmental abnormalities. Physical features may include an u...

Mucolipidosis IV is a rare inherited metabolic disorder believed to be characterized by a deficiency of transport channel receptor protein, based upon the recent discovery of the Mucolipidosis IV gene. This deficiency may lead to the accumulation ...

Gaucher disease is an inherited disorder of metabolism that interferes with many body functions. There are different forms of Gaucher disease. The perinatal lethal form is the most severe type of Gaucher disease. ...

Wernicke syndrome and Korsakoff syndrome are related disorders that often occur due to a deficiency of thiamine (vitamin B1). Wernicke's syndrome, also known as Wernicke encephalopathy, is a neurological disease characterized by the clinical triad...

Krabbe's Leukodystrophy is a rare inherited lipid storage disorder caused by a deficiency of the enzyme galactocerebrosidase (GALC), which is necessary for the breakdown (metabolism) of the sphingolipids galactosylceremide and psychosine. Failure ...

Pierre Robin sequence is characterized by an unusually small lower jaw (micrognathia) and downward displacement of the tongue (glossoptosis). Some infants also have an abnormal opening in the roof of the mouth (cleft palate); both the soft and har...

Gonorrhea is a sexually transmitted infection (STI) caused by the bacterium Neisseria gonorrhoeae. It can infect both men and women and is most commonly spread through unprotected sexual contact. Symptoms of gonorrhea can include painful urination...

Group B strep facts Group B strep are bacteria found normally in the intestine, vagina, and rectal area in about 25% of all healthy women. Group B strep infections can affect neonates and adults. Most pregnant wo...

SHORT syndrome is a condition in which affected individuals have multiple birth defects in different organ systems. The term SHORT is an acronym with each letter representing one of the common findings in affected persons:(S)= short st...

Congenital central hypoventilation syndrome (CCHS) is a rare disorder of respiratory control with autonomic nervous system dysregulation (ANSD). The autonomic nervous system is the portion of the nervous system that controls or regulates certain i...

Hallermann-Streiff syndrome (HSS) is a rare genetic disorder that is primarily characterized by distinctive malformations of the skull and facial (craniofacial) region; sparse hair (hypotrichosis); eye abnormalities; dental defects; degenerative s...

Hallermann-Streiff syndrome (HSS) is a rare genetic disorder that is primarily characterized by distinctive malformations of the skull and facial (craniofacial) region; sparse hair (hypotrichosis); eye abnormalities; dental defects; degenerative s...

Walker-Warburg syndrome (WWS) is a rare multisystem disorder characterized by muscle, brain and eye abnormalities, often leading to death in the first weeks of life. However, the specific symptoms and severity of WWS can vary greatly from case to ...

Harlequin ichthyosis is a rare genetic skin disorder. The newborn infant is covered with plates of thick skin that crack and split apart. The thick plates can pull at and distort facial features and can restrict breathing and eating. Harlequin inf...

Hartnup disease is a rare metabolic disorder inherited as an autosomal recessive trait. It involves an inborn error of amino acid metabolism as well as niacin deficiency. Factors that may precipitate acute attacks of this disorder may include poor...

Hay-Wells syndrome, also known as ankyloblepharon-ectodermal dysplasia-clefting (AEC) syndrome, is a rare inherited disorder that belongs to a group of disorders known as the ectodermal dysplasias. Major characteristics of Hay-Wells syndrome inclu...

Autosomal recessive hyper IgE syndrome (AR-HIES) is a very rare primary immunodeficiency disorder. Symptoms often become apparent at birth or early during infancy or childhood. The disorder is characterized by the triad of highly elevated levels o...

Sprengel Deformity is a rare congenital disorder in which the shoulder blade is displaced upward. The elevated shoulder blade causes a lump in the back of the base of the neck and may limit movement of the arm on the affected side. This disorder t...

Holoprosencephaly (HPE) is the failure of the prosencephalon, or forebrain, to develop normally. The forebrain is a region of the brain in the fetus that develops into parts of the adult brain, including the cerebral cortex. Instead of the normal ...

Human Papillomavirus (HPV) is a group of viruses that can infect the skin and mucous membranes of humans. There are over 100 different types of HPV, some of which can cause genital warts and others that can lead to various types of cancer, includi...

Bowen Hutterite syndrome is a rare genetic disorder that is apparent at birth (congenital). The disorder is characterized by growth delays before birth (intrauterine growth retardation); failure to grow and gain weight at the expected rate (failur...

Hydrocele facts While hydroceles may occur in either gender, they are much more common in males. A hydrocele is a collection of clear fluid in a thin walled sack present in the scrotum. Hydroceles may be either o...

Carbamoyl phosphate synthetase I deficiency (CPSID) is a rare inherited disorder characterized by complete or partial lack of the carbamoyl phosphate synthetase (CPS) enzyme. This is one of five enzymes that play a role in the breakdown and remova...

Ornithine transcarbamylase (OTC) deficiency is a rare X-linked genetic disorder characterized by complete or partial lack of the enzyme ornithine transcarbamylase (OTC). OTC is one of six enzymes that play a role in the break down and removal of n...

Williams syndrome, also known as Williams-Beuren syndrome, is a rare genetic disorder characterized by growth delays before and after birth (prenatal and postnatal growth retardation), short stature, a varying degree of mental deficiency, and dist...

CHILD syndrome (an acronym for congenital hemidysplasia with ichthyosiform erythroderma and limb defects) is an inherited disorder, affecting primarily women, that is characterized by ichthyosis-like skin abnormalities and limb defects on one side...

Sjogren-Larsson syndrome is an inherited disorder characterized by scaling skin (ichthyosis), mental retardation, speech abnormalities, and spasticity. Affected infants develop various degrees of reddened skin with fine scales soon after birth. Af...

Sjogren-Larsson syndrome is an inherited disorder characterized by scaling skin (ichthyosis), mental retardation, speech abnormalities, and spasticity. Affected infants develop various degrees of reddened skin with fine scales soon after birth. Af...

Familial idiopathic basal ganglia calcification (FIBGC) is a rare neurological disorder characterized by the presence of abnormal calcium deposits (calcifications) of unknown cause. Associated symptoms include progressive deterioration of cognitiv...

The WAS-related disorders are a spectrum of conditions affecting the immune system that are caused by mutations in the WAS gene. These disorders include Wiskott-Aldrich syndrome, X-linked thrombocytopenia and X-linked congenital neutropenia. The W...

Apnea is a term used to describe the temporary absence of spontaneous breathing. Infantile apnea occurs in children under the age of one year. Apnea may occur because of neurological impairment of the respiratory rhythm or obstruction of air flow ...

Gaucher disease is a rare, inherited metabolic disorder in which deficiency of the enzyme glucocerebrosidase results in the accumulation of harmful quantities of certain fats (lipids), specifically the glycolipid glucocerebroside, throughout the b...

West syndrome is a type of epilepsy characterized by spasms, abnormal brain wave patterns called hypsarrhythmia and sometimes mental retardation. The spasms that occur may range from violent jackknife or "salaam" movements where the whole body ben...

Santavuori disease, a rare genetic disorder, belongs to a group of progressive degenerative neurometabolic diseases known as the neuronal ceroid lipofuscinoses (NCL). These disorders share certain similar symptoms and are distinguished in part by ...

Fetal retinoid syndrome is a characteristic pattern of mental and physical birth defects that results from maternal use of retinoids, the synthetic derivatives of vitamin A, during pregnancy. The most well known retinoid is isotretinoin (Accutane)...

Fetal retinoid syndrome is a characteristic pattern of mental and physical birth defects that results from maternal use of retinoids, the synthetic derivatives of vitamin A, during pregnancy. The most well-known retinoid is isotretinoin (Accutane)...

General DiscussionIvemark syndrome is a rare disorder that affects multiple organ systems of the body. It is characterized by the absence (asplenia) or underdevelopment (hypoplasia) of the spleen, malformations of the heart and the abnorm...

wJansen type metaphyseal chondrodysplasia is an extremely rare progressive disorder in which portions of the bones of the arms and legs develop abnormally with unusual cartilage formations and subsequent abnormal bone formation at the large (bulbo...

Jansen type metaphyseal chondrodysplasia is an extremely rare progressive disorder in which portions of the bones of the arms and legs develop abnormally with unusual cartilage formations and subsequent abnormal bone formation at the large (bulbou...

Jansen type metaphyseal chondrodysplasia is an extremely rare progressive disorder in which portions of the bones of the arms and legs develop abnormally with unusual cartilage formations and subsequent abnormal bone formation at the large (bulbou...

General DiscussionJervell and Lange-Nielsen syndrome (JLNS) is a rare inherited disorder characterized by deafness present at birth (congenital) occurring in association with abnormalities affecting the electrical system of the heart. The...

Asphyxiating thoracic dystrophy is a very rare form of congenital dwarfism affecting the development of the bone structure, particularly of the chest (thorax) but also of the legs and arms. Typical, major characteristics include failure of the rib...

Joubert syndrome is an autosomal recessive genetic disorder that affects the area of the brain that controls balance and coordination. This condition is characterized by a specific finding on an MRI called a "molar tooth sign" in which the cerebel...

Joubert syndrome is an autosomal recessive genetic disorder that affects the area of the brain that controls balance and coordination. This condition is characterized by a specific finding on an MRI called a "molar tooth sign" in which the cerebel...

X-linked juvenile retinoschisis (RS) is a genetic disorder affecting males. Major symptoms include poor eyesight and degeneration of the retina. The retina consists of membrane layers in the eye that receive visual images. It is composed of suppor...

Kugelberg Welander syndrome is a milder type of spinal muscular atrophy. It is a rare inherited neuromuscular disorder characterized by wasting and weakness in the muscles of the arms and legs, leading to walking difficulties in, and eventual loss...

Kabuki syndrome is a rare, multisystem disorder characterized by multiple abnormalities including distinctive facial features, growth delays, varying degrees of intellectual disability, skeletal abnormalities, and short stature. A wide variety of ...

Kenny-Caffey syndrome type 2 (KCS2) is an extremely rare hereditary skeletal disorder characterized by thickening of the long bones, thin marrow cavities in the bones (medullary stenosis), and abnormalities affecting the head and eyes. Most cases ...

Erythrokeratolysis hiemalis is an extremely rare form of ichthyosis that was first described in South Africa but has subsequently been identified in other countries. In such cases, a link to South Africa has been determined. The disorder is charac...

Keratosis follicularis, also known as Darier disease, is a rare, genetic skin disorder. Affected individuals develop skin lesions that consist of thickened, rough bumps (papules) or plaques that may also be greasy or have a brown or yellow crust. ...

Meleda disease is an extremely rare inherited skin disorder characterized by the slowly progressive development of dry, thick patches of skin on the palms of the hands and soles of the feet (palmoplantar hyperkeratosis). Affected skin may be unusu...

Klippel-Feil syndrome (KFS) is a rare skeletal disorder primarily characterized by abnormal union or fusion of two or more bones of the spinal column (vertebrae) within the neck (cervical vertebrae). Some affected individuals may also have an abno...

Kluver-Bucy syndrome is a very rare cerebral neurological disorder associated with damage to both temporal lobes resulting in abnormalities in memory, social and sexual functioning and idiosyncratic behaviors....

Kugelberg Welander syndrome is a milder type of spinal muscular atrophy. It is a rare inherited neuromuscular disorder characterized by wasting and weakness in the muscles of the arms and legs, leading to walking difficulties in, and eventual loss...

Laband syndrome, also known as Zimmerman-Laband syndrome, is an extremely rare genetic disorder characterized by abnormalities of the head and facial (craniofacial) area and the hands and feet. Most children with this disorder have abnormally larg...

Cri du chat syndrome (CdCS or 5p-) is a rare genetic disorder in which a variable portion of the short arm of chromosome 5 is missing or deleted (monosomic). Symptoms vary greatly from case to case depending upon the exact size and location of the...

A lipoma is a slow-growing, fatty lump that's most often situated between your skin and the underlying muscle layer. A lipoma, which feels doughy and usually isn't tender, moves readily with slight finger pressure. Lipomas are usually detected in ...

Sneddon syndrome is a rare progressive disorder affecting the blood vessels characterized by the association of a skin condition and neurological abnormalities. Characteristics include multiple episodes of reduced blood flow to the brain (cerebral...

Ataxia telangiectasia (AT) is a complex genetic neurodegenerative disorder that may become apparent during infancy or early childhood. The disorder is characterized by progressively impaired coordination of voluntary movements (ataxia), the develo...

Lowe syndrome is characterized by vision problems including clouding of the lenses of the eyes (cataracts) that are present at birth, kidney problems that usually develop in the first year of life, and brain abnormalities that are associated with ...

Lowe syndrome is characterized by vision problems including clouding of the lenses of the eyes (cataracts) that are present at birth, kidney problems that usually develop in the first year of life, and brain abnormalities that are associated with ...

Lowe syndrome is characterized by vision problems including clouding of the lenses of the eyes (cataracts) that are present at birth, kidney problems that usually develop in the first year of life, and brain abnormalities that are associated with ...

Alpha-mannosidosis is a rare genetic disorder characterized by a deficiency of the enzyme alpha-D-mannosidase. Alpha-mannosidosis is best thought of as a continuum of disease that is generally broken down into three forms: a mild, slowly progressi...

Atypical mole syndrome, also called dysplastic nevus syndrome, is a disorder of the skin characterized by the presence of many mole-like tumors (nevi). Most people have 10-20 moles over their bodies. People with this syndrome often have more than ...

Treacher Collins syndrome (TCS) is a rare genetic disorder characterized by distinctive abnormalities of the head and face area resulting from underdevelopment (hypoplasia) of certain facial structures including the jaw, cheekbones and nearby stru...

Alpha-mannosidosis is a rare genetic disorder characterized by a deficiency of the enzyme alpha-D-mannosidase. Alpha-mannosidosis is best thought of as a continuum of disease that is generally broken down into three forms: a mild, slowly progressi...

Osteopetrosis may be inherited as either a dominant or recessive trait and is marked by increased bone density, brittle bones, and, in some cases, skeletal abnormalities. Although symptoms may not initially be apparent in people with mild forms of...

Marcus Gunn phenomenon is a rare genetic disorder that is usually present at birth. It is characterized by the movement of one upper eyelid in a rapid rising motion each time the jaw moves. Other eye abnormalities and vision difficulties may also ...

Marinesco-Sjogren syndrome (MSS) is a rare genetic disorder that affects multiple organ systems of the body. Common symptoms include difficulty coordinating voluntary movements due to degeneration (atrophy) of the cerebellum (cerebellar ataxia), c...

Microvillus inclusion disease is an extremely rare inherited intestinal disorder (enteropathy) that is typically apparent within hours or days after birth. The disorder is characterized by chronic, severe, watery diarrhea and insufficient absorpti...

Megalocornea-mental retardation (MMR) syndrome, otherwise known as Neuhauser syndrome, is an extremely rare genetic disorder characterized by distinctive abnormalities of the eye, several degrees of cognitive impairment, and a wide variety of addi...

Peripheral neuropathy is an umbrella term that denotes a disorder of, or damage to, the peripheral nervous system. The peripheral nervous system consists of all the motor and sensory nerves that connect the brain and spinal cord to the rest of the...

Chromosome 9, Partial Monosomy 9p is a rare chromosomal disorder in which there is deletion (monosomy) of a portion of the 9th chromosome. Characteristic symptoms and findings include mental retardation; distinctive malformations of the skull and ...

Turner syndrome is a rare chromosomal disorder that affects females. The disorder is characterized by partial or complete loss (monosomy) of one of the X chromosomes. Turner syndrome is highly variable and can differ dramatically from one person t...

Morquio syndrome (mucopolysaccharidosis type IV; MPS IV) is a mucopolysaccharide storage disease that exists in two forms (Morquio syndromes A and B) and occurs because of a deficiency of the enzymes N-acetyl-galactosamine-6-sulfatase and beta-gal...

I-cell disease (mucolipidosis II) is a rare inherited metabolic disorder characterized by coarse facial features, skeletal abnormalities and mental retardation. The symptoms of I-cell disease are similar to but more severe than those of Hurler syn...

General DiscussionPseudo-Hurler polydystrophy (mucolipidosis type III) is a rare genetic metabolic disorder characterized by a defective enzyme known as UPD-N-acetylglucosamine-1-phosphotransferase. This defective enzyme ultimately result...

The mucopolysaccharidoses (MPS) are a group of inherited lysosomal storage disorders. Lysosomes function as the primary digestive units within cells. Enzymes within lysosomes break down or digest particular nutrients, such as certain carbohydrates...

Morquio syndrome (mucopolysaccharidosis type IV; MPS IV) is a mucopolysaccharide storage disease that exists in two forms (Morquio syndromes A and B) and occurs because of a deficiency of the enzymes N-acetyl-galactosamine-6-sulfatase and beta-gal...

Mulibrey nanism is an extremely rare autosomal recessive genetic disorder characterized by profound growth delays and distinctive abnormalities of the muscles, liver, brain, and eyes. The acronym MULIBREY stands for (MU)scle, (LI)ver, (BR)ain, and...

Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome is a rare disorder that affects women. It is characterized by the failure of the uterus and the vagina to develop properly in women who have normal ovarian function and normal external genitalia. Wome...

Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome is a rare disorder that affects women. It is characterized by the failure of the uterus and the vagina to develop properly in women who have normal ovarian function and normal external genitalia. Wome...

Ollier disease is a rare skeletal disorder characterized by abnormal bone development (skeletal dysplasia). While this disorder may be present at birth (congenital); it may not become apparent until early childhood when symptoms, such as deformiti...

Hereditary multiple osteochondromas (HMO) is a rare genetic disorder characterized by multiple benign (noncancerous) bone tumors that are covered by cartilage (osteochondromas), often on the growing end (metaphysis) of the long bones of the legs, ...

Multiple epiphyseal dysplasia (MED) is a rare inherited spectrum of disorders characterized by malformation (dysplasia) of the "growing portion" or head of the long bones (epiphyses). Affected individuals may have an abnormally short thighbone (fe...

Hereditary multiple osteochondromas (HMO) is a rare genetic disorder characterized by multiple benign (noncancerous) bone tumors that are covered by cartilage (osteochondromas), often on the growing end (metaphysis) of the long bones of the legs, ...

Multiple pterygium syndrome is a very rare genetic disorder characterized by minor facial anomalies, short stature, vertebral defects, multiple joints in a fixed position (contractures) and webbing (pterygia) of the neck, inside bend of the elbows...

Nager Syndrome is a rare disorder that may or may not be genetically derived. Major symptoms may include underdevelopment of the cheek and jaw area of the face. Down-sloping of the opening of the eyes, a smaller than normal jaw, lack or absence of...

Nail-patella syndrome (NPS) is a rare genetic disorder that is usually apparent at birth or during early childhood. Although the symptoms and physical characteristics associated with NPS may vary, characteristic abnormalities tend to include impro...

Nance-Horan syndrome is a rare genetic disorder that may be evident at birth (congenital). It is primarily characterized by abnormalities of the teeth and clouding of the lens of the eyes (congenital cataracts), resulting in poor vision. Additiona...

Binder type maxillonasal dysplasia is a rare condition characterized by abnormal development (dysplasia) of the nasal and upper jaw (nasomaxillary) regions. Affected individuals typically have an unusually flat, underdeveloped midface (midfacial h...

Kabuki syndrome is a rare, multisystem disorder characterized by multiple abnormalities including distinctive facial features, growth delays, varying degrees of intellectual disability, skeletal abnormalities, and short stature. A wide variety of ...

Idiopathic nodular panniculitis is a rare spectrum of skin disorders characterized by single or multiple, tender or painful bumps below the surface of the skin (subcutaneous nodules) that usually lead to inflammation of the subcutaneous layer of f...

Nonketotic hyperglycinemia is an inborn error of metabolism characterized by the accumulation of large amounts of the amino acid glycine in blood, urine and, particularly, the cerebrospinal fluid (CSF). The metabolic block occurs in the conversion...

Red cell pyruvate kinase deficiency is a hereditary blood disorder characterized by a deficiency of the enzyme pyruvate kinase. Physical findings associated with the disorder may include reduced levels of oxygen-carrying hemoglobulin in the blood ...

Henoch-Schonlein purpura is a rare inflammatory disease of the small blood vessels (capillaries) and is usually a self-limited disease. It is the most common form of childhood vascular inflammation (vasculitis) and results in inflammatory changes ...

Norrie disease is a rare X-linked disorder that occurs due to errors or disruption (mutations) of the NDP gene. All males are affected by loss of vision present at birth or shortly thereafter. Additional symptoms may occur in some case...

Nail-patella syndrome (NPS) is a rare genetic disorder that is usually apparent at birth or during early childhood. Although the symptoms and physical characteristics associated with NPS may vary, characteristic abnormalities tend to include impro...

Ovarian cysts facts Ovarian cysts are closed, sac-like structures within the ovary that are filled with a liquid or semisolid substance. Ovarian cysts form for numerous reasons. Pain in the abdomen or pelvis is t...

Turner syndrome is a rare chromosomal disorder that affects females. The disorder is characterized by partial or complete loss (monosomy) of one of the X chromosomes. Turner syndrome is highly variable and can differ dramatically from one person t...

Tachycardia is when your heart beats faster than normal, even when you’re not doing anything. Paroxysmal supraventricular tachycardia (PSVT) is when your fast heartbeat starts in the upper, or supraventricular, chambers of the heart. It&rsqu...

Hydrocele facts While hydroceles may occur in either gender, they are much more common in males. A hydrocele is a collection of clear fluid in a thin walled sack present in the scrotum. Hydroceles may be either o...

Pelvic Inflammatory Disease (PID) is an infection of the female reproductive organs, including the uterus, fallopian tubes, and ovaries. It is usually caused by sexually transmitted infections such as chlamydia and gonorrhea, but can also be cause...

Pierre Robin sequence is characterized by an unusually small lower jaw (micrognathia) and downward displacement of the tongue (glossoptosis). Some infants also have an abnormal opening in the roof of the mouth (cleft palate); both the soft and har...

Pierre Robin sequence is characterized by an unusually small lower jaw (micrognathia) and downward displacement of the tongue (glossoptosis). Some infants also have an abnormal opening in the roof of the mouth (cleft palate); both the soft and har...

Pierre Robin sequence is characterized by an unusually small lower jaw (micrognathia) and downward displacement of the tongue (glossoptosis). Some infants also have an abnormal opening in the roof of the mouth (cleft palate); both the soft and har...

Catel-Manzke syndrome is a rare genetic disorder characterized by distinctive abnormalities of the index fingers; the classic features of Pierre Robin syndrome; and, in some cases, additional physical findings. Pierre Robin syndrome refers to a se...

Propionic acidemia is a rare metabolic disorder affecting from 1/20,000 to 1/250,000 individuals in various regions of the world. It is characterized by deficiency of propionyl-CoA carboxylase, an enzyme involved in the breakdown (catabolism) of t...

Propionic acidemia is a rare metabolic disorder affecting from 1/20,000 to 1/250,000 individuals in various regions of the world. It is characterized by deficiency of propionyl-CoA carboxylase, an enzyme involved in the breakdown (catabolism) of t...

Thrombocytopenia-absent radius (TAR) syndrome is a rare disorder that is present at birth (congenital). It is characterized by low levels of platelets in the blood (thrombocytopenia) and absence (aplasia) of the long, thin bones of the forearms (r...

Camurati-Engelmann disease is a rare genetic disorder characterized by progressive widening and malformation of the shafts of the long bones (diaphyseal dysplasia). Major symptoms may include bone pain, particularly in the legs; skeletal abnormali...

Chromosome 21 Ring is a rare chromosomal disorder in which the affected infant has a breakage of chromosome 21 at both ends, and the ends of the chromosome join together to form a ring. The amount of genetic material lost at the two ends of the ch...

Phocomelia syndrome (PS) is a rare birth defect that causes severe birth defects, especially of the upper limbs. The bones of the arms, and in some cases other appendages, may be extremely shortened and even absent. The fingers of the hands may be...

Roberts syndrome is a rare genetic disorder characterized by growth delays before and after birth (pre- and postnatal growth deficiency); malformations of the arms and legs (limbs); distinctive abnormalities of the skull and facial (craniofacial) ...

Pierre Robin sequence is characterized by an unusually small lower jaw (micrognathia) and downward displacement of the tongue (glossoptosis). Some infants also have an abnormal opening in the roof of the mouth (cleft palate); both the soft and har...

Robinow syndrome is an extremely rare inherited disorder characterized by mild to moderate short stature due to growth delays after birth (postnatal growth retardation); distinctive abnormalities of the head and facial (craniofacial) area; additio...

Budd-Chiari syndrome is a rare disorder characterized by narrowing and obstruction (occlusion) of the veins of the liver (hepatic veins). Symptoms associated with Budd Chiari syndrome include pain in the upper right part of the abdomen, an abnorma...

Rosenberg-Chutorian syndrome is an extremely rare genetic disorder characterized by the triad of hearing loss, degeneration of the optic nerve (optic atrophy) and neurological abnormalities, specifically disease of the nerves outside of the centra...

Rothmund-Thomson syndrome (RTS) is a rare genetic disorder that can affect many parts of the body. The disorder is characterized by distinctive abnormalities of the skin, sparse hair, eyelashes and/or eyebrows, small stature, skeletal and dental a...

Rubinstein-Taybi syndrome is a rare genetic multisystem disorder that affects many organ systems of the body. The group of findings (constellation) associated with this syndrome include growth retardation and delayed bone age; mental retardation; ...

Rubinstein-Taybi syndrome is a rare genetic multisystem disorder that affects many organ systems of the body. The group of findings (constellation) associated with this syndrome include growth retardation and delayed bone age; mental retardation; ...

The diencephalic syndrome is a very rare neurological disorder characterized by failure to thrive, abnormal thinness (emaciation), amnesia, intense sleepiness, unusual eye position and sometimes blindness. It is normally seen in infancy or early c...

The diencephalic syndrome is a very rare neurological disorder characterized by failure to thrive, abnormal thinness (emaciation), amnesia, intense sleepiness, unusual eye position and sometimes blindness. It is normally seen in infancy or early c...

Sandhoff disease is a lipid storage disorder characterized by a progressive deterioration of the central nervous system. The clinical symptoms of Sandhoff disease are identical to Tay-Sachs disease. Sandhoff disease is an autosomal recessive genet...

General DiscussionPhocomelia syndrome (PS) is a rare birth defect that causes severe birth defects, especially of the upper limbs. The bones of the arms, and in some cases other appendages, may be extremely shortened and even absent. The ...

Aplasia Cutis Congenita is a rare disorder with a complicated pattern of inheritance. Babies are born with the absence of certain layer(s) of skin, most often on the scalp, but also on the trunk, and/or arms and legs. The affected area is typicall...

Turner syndrome is a rare chromosomal disorder that affects females. The disorder is characterized by partial or complete loss (monosomy) of one of the X chromosomes. Turner syndrome is highly variable and can differ dramatically from one person t...

Adrenoleukodystrophy is an X-linked recessive genetic disorder caused by an abnormality in the ABCD1 gene on the X chromosome. This condition affects the white matter of the nervous system and the adrenal cortex. Some affected individuals have adr...

Coffin-Siris syndrome is a rare genetic disorder that may be evident at birth (congenital). The disorder may be characterized by feeding difficulties and frequent respiratory infections during infancy, diminished muscle tone (hypotonia), abnormal ...

Weismann-Netter-Stuhl syndrome is an extremely rare genetic skeletal disorder characterized by the abnormal development of bone (osseousbo dysplasia). Affected individuals exhibit bowing of the long portions (shafts) of the shinbone (tibia) and th...

Dyggve-Melchior-Clausen (DMC) syndrome is a rare, progressive genetic disorder characterized by abnormal skeletal development, microcephaly and intellectual disability. The condition was first reported by Dyggve, Melchior and Clausen in 1962 in th...

General DiscussionSneddon syndrome is a rare progressive disorder affecting the blood vessels characterized by the association of a skin condition and neurological abnormalities. Characteristics include multiple episodes of reduced blood ...

Familial idiopathic basal ganglia calcification (FIBGC) is a rare neurological disorder characterized by the presence of abnormal calcium deposits (calcifications) of unknown cause. Associated symptoms include progressive deterioration of cognitiv...

General DiscussionEndocardial fibroelastosis (EFE) is a rare heart disorder that affects infants and children. It is characterized by a thickening within the muscular lining of the heart chambers due to an increase in the amount of suppor...

Filippi syndrome is an extremely rare genetic disorder that may be apparent at birth (congenital). The disorder is characterized by an unusual facial appearance, abnormalities of the fingers and toes, and mild to severe mental retardation. Primary...

Pseudoxanthoma elasticum, PXE, is an inherited disorder caused y mutations in the ABCC6 transporter gene that affects connective tissue in some parts of the body. Elastic tissue in the body becomes mineralized; that is, calcium and other minerals ...

POEMS syndrome is an extremely rare multisystem disorder. POEMS is an acronym that stands for (P)olyneuropathy, disease affecting many nerves; (O)rganomegaly, abnormal enlargement of an organ; (E)ndocrinopathy, disease affecting certain hormone-pr...

Treacher Collins syndrome (TCS) is a rare genetic disorder characterized by distinctive abnormalities of the head and face area resulting from underdevelopment (hypoplasia) of certain facial structures including the jaw, cheekbones and nearby stru...

Tricho-dento-osseous (TDO) syndrome is an autosomal dominant genetic disorder that belongs to a group of diseases known as ectodermal dysplasias. Ectodermal dysplasias typically affect the hair, teeth, nails, and/or skin. TDO syndrome is character...

Central pain syndrome is a neurological disorder caused by damage to the central nervous system (CNS). Common symptoms include pain and loss of sensation, usually in the face, arms and/or legs. Pain is often constant and can be mild, moderate, or ...

Thrombocytopenia-absent radius (TAR) syndrome is a rare disorder that is present at birth (congenital). It is characterized by low levels of platelets in the blood (thrombocytopenia) and absence (aplasia) of the long, thin bones of the forearms (r...

Thrombocytopenia-absent radius (TAR) syndrome is a rare disorder that is present at birth (congenital). It is characterized by low levels of platelets in the blood (thrombocytopenia) and absence (aplasia) of the long, thin bones of the forearms (r...

Ataxia with vitamin E deficiency (AVED) is a rare inherited neurodegenerative disorder characterized by impaired ability to coordinate voluntary movements (ataxia) and disease of the peripheral nervous system (peripheral neuropathy). AVED is a pro...

General DiscussionTownes-Brocks syndrome (TBS) is an autosomal dominant genetic disorder characterized by absence of the anal opening (imperforate anus), abnormal ears associated with hearing impairment and thumb malformations. Abnormalit...

Weismann-Netter-Stuhl syndrome is an extremely rare inherited skeletal disorder characterized by the abnormal development of bone (osseous dysplasia). Affected individuals exhibit bowing of the long portions (shafts) of the shinbone (tibia) and th...

Esophageal atresia (EA) is a rare birth defect in which the esophagus (the tube that connects the throat with the stomach) does not develop normally. In infants with EA, the esophagus is usually separated into two parts, an upper and lower segment...

Treacher Collins syndrome (TCS) is a rare genetic disorder characterized by distinctive abnormalities of the head and face area resulting from underdevelopment (hypoplasia) of certain facial structures including the jaw, cheekbones and nearby stru...

Trichorhinophalangeal syndrome type I (TRPS1) is an extremely rare inherited multisystem disorder. TRPS1 is characterized by thin, sparse scalp hair, unusual facial features, abnormalities of the fingers and/or toes, and multiple abnormalities of ...

Trichorhinophalangeal syndrome type II (TRPS2), also known as Langer-Giedion syndrome, is an extremely rare inherited multisystem disorder. TRPS2 is characterized by fine, thin hair; unusual facial features; progressive growth retardation resultin...

Trichorhinophalangeal syndrome type III (TRPS3), also known as Sugio-Kajii syndrome, is an extremely rare inherited multisystem disorder. TRPS3 is characterized by fine, thin light-colored hair; unusual facial features; abnormalities of the finger...

C syndrome, also known as Opitz trigonocephaly syndrome, is a rare disorder transmitted as a result of "gonadal mosaicism". Mosaicism refers to a condition in which a person has cells that differ from each other in genetic makeup. The difference i...

Schinzel syndrome, also known as ulnar-mammary syndrome, is a rare inherited disorder characterized by abnormalities of the bones of the hands and forearms in association with underdevelopment (hypoplasia) and dysfunction of certain sweat (apocrin...

Porphyria cutanea tarda (PCT) is a type of porphyria in which affected individuals are sensitive to sunlight. Exposed skin shows abnormalities that range from slight fragility of the skin to persistent scarring and disfiguration. Due to fragility ...

Porphyria cutanea tarda (PCT) is a type of porphyria in which affected individuals are sensitive to sunlight. Exposed skin shows abnormalities that range from slight fragility of the skin to persistent scarring and disfiguration. Due to fragility ...

The uterus The uterus is part of a woman's reproductive system. It's a hollow organ in the pelvis. The uterus has three parts: Top: The top (fundus) of your uterus is shaped like a dome. From the top of your ut...

Vaginal cancer is a disease in which malignant (cancer) cells form in the vagina. The vagina is the canal leading from the cervix (the opening of uterus) to the outside of the body. At birth, a baby passes out of the body through the vagin...

Gorham's disease (GD) is an extremely rare bone disorder; fewer than 200 cases are reported in the medical literature. It is characterized by bone loss (osteolysis) often associated with swelling or abnormal blood vessel growth (angiomatous prolif...

Congenital Varicella Syndrome is an extremely rare disorder in which affected infants have distinctive abnormalities at birth (congenital) due to the mother's infection with chickenpox (maternal varicella zoster) early during pregnancy (i.e., up t...

General DiscussionChromosome 22q11.2 deletion syndrome is associated with a range of problems including: congenital heart disease, palate abnormalities, immune system dysfunction including autoimmune disease, low calcium (hypocalcemia) an...

Joubert syndrome is an autosomal recessive genetic disorder that affects the area of the brain that controls balance and coordination. This condition is characterized by a specific finding on an MRI called a "molar tooth sign" in which the cerebel...

WAGR syndrome/11p deletion syndrome is a rare genetic syndrome in which there is a predisposition to several conditions, including certain malignancies, distinctive eye abnormalities, and/or intellectual disability. "WAGR" is an acronym for the ch...

Walker-Warburg syndrome (WWS) is a rare multisystem disorder characterized by muscle, brain and eye abnormalities, often leading to death in the first weeks of life. However, the specific symptoms and severity of WWS can vary greatly from case to ...

Walker-Warburg syndrome (WWS) is a rare multisystem disorder characterized by muscle, brain and eye abnormalities, often leading to death in the first weeks of life. However, the specific symptoms and severity of WWS can vary greatly from case to ...

Stickler syndrome refers to a group of disorders of connective tissue. Connective tissue, which is distributed throughout the body, multiple organ systems can be affected. The specific symptoms present in Stickler syndrome often vary greatly from ...

Familial eosinophilic cellulitis is a rare skin disorder. It is characterized by raised, red, swollen, and warm areas of skin, in a flame-shaped pattern with associated pain. The exact cause of the disease is unknown. However, bites of spiders, be...

Wernicke syndrome and Korsakoff syndrome are related disorders that often occur due to a deficiency of thiamine (vitamin B1). Wernicke's syndrome, also known as Wernicke encephalopathy, is a neurological disease characterized by the clinical triad...

West syndrome is a type of epilepsy characterized by spasms, abnormal brain wave patterns called hypsarrhythmia and sometimes mental retardation. The spasms that occur may range from violent jackknife or "salaam" movements where the whole body ben...

Wieacker syndrome is a rare, slowly progressive, genetic disorder characterized by deformities of the joints of the feet (contracture), muscle degeneration (atrophy), mild mental retardation and an impaired ability to move certain muscles of the e...

Wildervanck syndrome, also known as cervicooculoacoustic syndrome, is a rare genetic disorder that primarily affects females. The disorder is characterized by a skeletal condition known as Klippel-Feil syndrome (KFS); abnormalities of certain eye ...

Williams syndrome, also known as Williams-Beuren syndrome, is a rare genetic disorder characterized by growth delays before and after birth (prenatal and postnatal growth retardation), short stature, a varying degree of mental deficiency, and dist...

Williams syndrome, also known as Williams-Beuren syndrome, is a rare genetic disorder characterized by growth delays before and after birth (prenatal and postnatal growth retardation), short stature, a varying degree of mental deficiency, and dist...

Denys-Drash syndrome (DDS) is characterized by abnormal kidney function (congenital nephropathy), a cancerous tumor of the kidney called Wilms tumor, and disorders of sexual development in affected males. Most affected females have normal genitali...

Weill Marchesani syndrome is a rare genetic disorder of connective tissue characterized by abnormalities of the lens of the eye, short stature, an unusually short, broad head (brachycephaly) and joint stiffness. The eye (ocular) abnormalities can ...

Werner Syndrome is a rare progressive disorder that is characterized by the appearance of unusually accelerated aging (progeria). Although the disorder is typically recognized by the third or fourth decades of life, certain characteristic findings...

Wyburn-Mason syndrome is an extremely rare nonhereditary disorder that is present at birth (congenital). Affected infants have arteriovenous malformations (AVMs), which are developmental abnormalities affecting the blood vessels, specifically the ...

Familial hypophosphatemia is a rare inherited disorder characterized by impaired transport of phosphate and often altered vitamin-D metabolism in the kidneys. In addition, phosphate may not be well-absorbed in the intestines. The hypophosphatemia ...

MCT8-specific thyroid hormone cell transporter deficiency (THCT deficiency) is an inherited disorder that is characterized by severe mental retardation, an impaired ability to speak, diminished muscle tone (hypotonia), and/or movement abnormalitie...

De Sanctis-Cacchione syndrome is an extremely rare disorder characterized by the skin and eye symptoms of xeroderma pigmentosum (XP) occurring in association with neurological abnormalities, mental retardation, unusually short stature (dwarfism), ...

Yunis-Varon syndrome is an extremely rare genetic multisystem disorder with defects affecting the skeletal system, ectodermal tissue (hair and teeth); and cardiorespiratory (i.e., heart and lungs) systems. It is characterized by large fontanelles,...