- Angelman syndrome
- An important genetic syndrome characterized by severe motor and intellectual retardation, microcephaly (abnormally small head), ataxia, frequent jerky limb movements and flapping of the arms and hands, hypotonia (floppiness), hyperactivity, seizures, absence of speech, frequent smiling and outbursts of laughter, and an unusual facies (facial appearance) characterized by macrostomia (large mouth), a large jaw and open-mouthed expression, and a great propensity for protruding the tongue (tongue thrusting). The name Angelman syndrome is now preferred because the old term "happy puppet syndrome" may appear derisive to the child's family. Angelman syndrome is due in most cases to a chromosome deletion involving loss of material from chromosome region 15q11-q13. The loss is consistently of the contribution of chromosome region 15q11-q13 from the mother. This loss is due to a new deletion in most cases. Deletion of chromosome region 15q11-q13 causes both Angelman syndrome and a totally different disorder called Prader-Willi syndrome. However, while the deleted chromosome is of maternal origin in Angelman syndrome, it is the paternal chromosome that is partially deleted in the Prader-Willi syndrome. There are rare families with more than one child with Angelman syndrome. The mode of inheritance in these families is autosomal dominant modified by imprinting.
* * *An·gel·man syndrome 'an-jəl-mən-, 'ān- also An·gel·man's syndrome -mənz- n a genetic disorder characterized by severe mental retardation, seizures, ataxic gait, jerky movements, lack of speech, microencephaly, and frequent smiling and laughterAngelman Harry (1915-1996)British pediatrician. Angelman began his career in pediatrics at Booth Hall Children's Hospital in Manchester, England. After serving with the Royal Medical Corps in India during World War II, he became a resident at the Royal Liverpool Children's Hospital. In 1950 he became a consultant pediatrician to a group of hospitals in Warrington. It was there in the early 1960s that he examined three children who seemed to be affected with the same genetic disorder. In the 1980s the Angelman Syndrome Foundation was established in the U.S. His description of the disorder was published in 1965, and the name Angelman syndrome subsequently came to be used.
* * *a disorder of development characterized by severe learning difficulties, absence of speech, seizures, jerky movements, a characteristic facial expression, and a happy social disposition. It is caused by a genetic abnormality on chromosome 15.H. Angelman (1915-96), British paediatrician
* * *An·gel·man syndrome (ānґjəl-mən) [Harry Angelman, British physician, 1915â€“1996] see under syndrome.
Medical dictionary. 2011.