A genetic syndrome characterized by mental retardation, speech impairment, microcephaly, ataxia, and seizures. The majority of cases result from deletions on the long arm of chromosome 15. A minority of cases result from mutations in the UBE3A gene.

A syndrome characterized by multiple abnormalities, MENTAL RETARDATION, and movement disorders. Present usually are skull and other abnormalities, frequent infantile spasms (SPASMS, INFANTILE); easily provoked and prolonged paroxysms of laughter (hence happy); jerky puppetlike movements (hence puppet); continuous tongue protrusion; motor retardation; ATAXIA; MUSCLE HYPOTONIA; and a peculiar facies. It is associated with maternal deletions of chromosome 15q11-13 and other genetic abnormalities. (From Am J Med Genet 1998 Dec 4;80(4):385-90; Hum Mol Genet 1999 Jan;8(1):129-35)

Angelman syndrome (AS) is characterized by severe developmental delay or intellectual disability, severe speech impairment, gait ataxia and/or tremulousness of the limbs, and unique behavior with an apparent happy demeanor that includes frequent laughing, smiling, and excitability. Microcephaly and seizures are also common. Developmental delays are first noted at around age six months; however, the unique clinical features of AS do not become manifest until after age one year.

(happy puppet syndrome) Autosomal recessive syndrome characterized by jerky puppetlike movements, frequent laughter, mental and motor retardation, peculiar open-mouthed faces, and seizures.

Angelman syndrome is a genetic disorder. It causes delayed development, problems with speech and balance, intellectual disability, and sometimes, seizures.

Angelman syndrome is a genetic disorder that primarily affects the nervous system. Characteristic features of this condition include developmental delay, intellectual disability, severe speech impairment, problems with movement and balance (ataxia), epilepsy, and a small head size. Individuals with Angelman syndrome typically have a...