 The Swedish study showed an AS prevalence of about 1/20,000 and the Danish study showed a minimum AS prevalence of about 1/10,000.Harry Angelman, a pediatrician working in Warrington, England, first reported three children with this condition in 1965.Angelman later described his choice of the title "Puppet Children" to describe these cases as being related to an oil painting he had seen while vacationing in Italy