Comparing Angelman Syndrome and Typical Developers Across the Lifespan

In 1965 Dr. Harry Angelman had been studying some peculiar features in three children. The children exhibited cognitive impairment (i.e., so called “mental retardation”), seizures, and spontaneous paroxysms of laughter. Further, because of their tendency to walk awkwardly, mixed with their happy demeanor, he called them “puppets.” Since that time many scientists, doctors, psychologists, and geneticists have become interested in what has been nicknamed the “happy puppet” syndrome. At first research was limited due to there only finding 70 cases worldwide by 1987. However since that time, there has been a significant increase in the diagnosing of Angelman syndrome. By 1993 there were over 140 cases worldwidewith over 300 in 1995. Today more than 1000 individuals have been given the diagnosis (Buntinx et al., 1995; Schneider & Maino, 1993; Fryburg, Breg, & Lindgren, 1991; Phillips, 1999).

There has been considerable research conducted on Angelman patients, but because the disorder is fairly new, with such an uncommon incidence, most doctors at best disagree on what the diagnostic criteria should include. Some commonalities have been found; these include profound global developmental delay, postnatal onset microcephaly, seizures, hyperkinesis, hypopigmentention, and normal appearance. Opthamalic, chroniofacial abnormalities, and a happy temperament are also typical symptoms.

One of the chief diagnostic difficulties regarding Angelmans syndrome is that many of the clinical markers onset after the age of two (e.g. pointy chin, seizures, etc.), and thus, due to their normal appearance in infancy and toddlerhood, many clinicians are slow to identify the disorder. Further, as there is no correlation with gestational trauma, remarkable familial history, or environmental constraint, clinicians often must wait for the disorder to manifest itself in behavior, or more often lack of appropriate developmental behavior in the child. Due to these factors many believe the incidence of Angelmans is much more significant than currently thought (Magenis et al., 1990), some estimating it as prevalent as 1 in 20,000 (Bottani et al., 1994), which, if true, would suggest that there are roughly 12, 500 cases in the United States that have not been diagnosed as of this writing.

-Heath Sommer
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