Background: Prader-Willi syndrome (PWS) is a genetic syndrome associated with several physical, cognitive and behavioural characteristics. For many individuals with this syndrome, compulsive behaviour is often noted in both food and non-food situations. The focus of this paper is on the non-food-related compulsions in individuals with PWS and…

Three models of behavioral effects of genetic disorders characterized by mental retardation were compared: (1) no-specific effect model (all genetic disorders have identical behavioral outcomes); (2) totally specific model (each genetic disorder has unique outcomes); and (3) partially specific model (two or more genetic disorders share outcomes…

This study compared maladaptive behavior in 23 people with Prader-Willi syndrome due to paternal deletion and in 23 age- and gender-matched subjects with maternal uniparental disomy. Controlling for IQs, the deletion cases showed significantly higher maladaptive ratings, more symptom-related distress, and more behavior problems. Findings suggest a…

A survey of the families of 62 persons with Prader-Willi syndrome examined the prevalence, topographies, and specific body locations of self-injurious behaviors. Self-injury was reported for 81% of the participants. Skin-picking was the most prevalent form with the front of the legs and head being disproportionately targeted. Incidence also varied…

This study examined Autism Diagnostic Interviews Revised (ADI-R) data for 69 autistic subjects from multiplex (MP) families (with more than one autistic member) and 88 autistic subjects from singleton (SP) families (with only one autistic member). Multivariate analysis revealed no differences between verbal or nonverbal MP and SP groups for ADI-R…

The maladaptive behaviors, personality, and language skills of a male whose chromosome analysis showed evidence of mosaicism with karyotype 49,XXXXY and 48,XXXY are described. Research on severity of mental handicap with extra chromosomes, delayed speech development, and discrepancy between verbal and performance intelligence is examined. (JDD)