Angelman Syndrome (AS) is a neuro-genetic disorder characterized by intellectual and developmental delay, sleep disturbance, seizures, jerky movements especially hand-flapping, frequent laughter or smiling, and usually a happy demeanor. AS is a classic example of genetic imprinting in that it is usually caused by deletion or inactivation of genes on the maternally inherited chromosome 15. The sister syndrome, Prader-Willi syndrome, is caused by a similar loss of paternally-inherited genes. AS is named after a British pediatrician, Dr. Harry Angelman, who first described the syndrome in 1965. An older, alternative term for AS, happy puppet syndrome, is generally considered pejorative and stigmatizing so it is no longer used, though it remains useful as a diagnostic heuristic. People with AS are sometimes known as "angels", both because of the syndrome's name and because of their youthful, happy appearance.
Angelman Syndrome History
Dr. Harry Angelman, a paediatrician working in Warrington (then in Lancashire) first reported three children with this condition in 1965.
Case reports from the United States first began appearing in the medical literature in the early 1980s. In 1987, it was first noted that around half of the children with AS have a small piece of chromosome 15 missing (''chromosome 15q partial deletion'').
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