Classical lissencephaly, also known as lissencephaly type I, is a brain malformation that may occur as an isolated abnormality (isolated lissencephaly sequence [ILS]) or in association with certain underlying syndromes (e.g., Miller-Dieker syndrom...

Antley-Bixler Syndrome is a rare genetic disorder that is primarily characterized by distinctive malformations of the head and facial (craniofacial) area and additional skeletal abnormalities. For example, the disorder is typically associated with...

Frey syndrome is a rare disorder that most often occurs as a result of surgery in the area near the parotid glands. The parotid glands are the largest salivary glands in the body located just below the ears on either side of the face. The main sym...

Baller-Gerold Syndrome is a rare genetic disorder that is apparent at birth (congenital). The disorder is characterized by distinctive malformations of the skull and facial (craniofacial) area and bones of the forearms and hands. In in...

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 ...

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...

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...

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...

Fragile X syndrome is characterized by moderate intellectual disability in affected males and mild intellectual disability in affected females. Distinctive physical features are sometimes present in affected males including a large head, long face...

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....

Paroxysmal cold hemoglobinuria (PCH) is a rare type of anemia characterized by the premature destruction of healthy red blood cells by autoantibodies. The disorder is classified as an autoimmune hemolytic anemia (AIHA), an uncommon group of disord...

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 ...

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 ...

Melasma facts Melasma is most common in women 20-50 years of age. Melasma looks like brown, tan, or blue-gray spots on the face (hyperpigmentation). Melasma is characterized by three location patterns (central fa...

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...

Antley-Bixler Syndrome is a rare genetic disorder that is primarily characterized by distinctive malformations of the head and facial (craniofacial) area and additional skeletal abnormalities. For example, the disorder is typically associated with...

Frey syndrome is a rare disorder that most often occurs as a result of surgery in the area near the parotid glands. The parotid glands are the largest salivary glands in the body located just below the ears on either side of the face. The main sym...

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 ...

Antley-Bixler Syndrome is a rare genetic disorder that is primarily characterized by distinctive malformations of the head and facial (craniofacial) area and additional skeletal abnormalities. For example, the disorder is typically associated with...

In ichthyosis vulgaris, the skin cells are produced at a normal rate, but they do not shed normally at the surface of the outermost layer of skin (stratum corneum) and are not shed as quickly as they should be. The result is a build-up of scale. F...

Weaver Syndrome is characterized by rapid growth. Usually starting before birth (prenatal onset), physical growth and bone development (maturation) can occur more quickly than average. Other symptoms can include increased muscle tone (hypertonia) ...

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. ...