Pervasive developmental disorders in Prader-Willi syndrome: the Leuven experience in 59 subjects and controls.

In the present study we investigated the co-morbidity of pervasive developmental disorder (PDD) in 59 Prader-Willi syndrome (PWS) individuals and in 59 non-specific mentally retarded controls, matched for IQ, gender, and age. The 'Pervasive Developmental Disorder Mentally Retardation Scale' (PDD-MRScale), a screening questionnaire based on the DSM-III-R criteria for PDD, has been applied in the PWS group and in the control group. Results of the present study revealed a striking autistic-like behavioral phenotype in the majority of the PWS individuals, particularly deficits in the quality of language and communication and of imagination and interests.

Psychotic disorders in Prader-Willi syndrome.

The Prader-Willi syndrome (PWS) is a genetically determined developmental disorder caused by abnormalities of the proximal region of chromosome 15q11-13. In a previous study, we reported that psychotic episodes, occurring in 16% of persons with PWS, had an onset in adolescence, never occurred in persons with paternal deletion, and were exclusively associated with maternal uniparental disomy (UPD) or imprinting abnormalities (IM). In order to gain a better understanding of the psychopathology and to further refine the psychiatric diagnosis, we describe in more detail the psychopathological manifestations of six adults with a history of psychotic episodes.

Prader-Willi syndrome: new insights in the behavioural and psychiatric spectrum.

Prader-Willi syndrome (PWS) is a genetic disorder caused by the loss of the paternal contribution of the proximal part (15q11-q13) of the long arm of chromosome 15 (i.e. deletion, disomy and imprinting mutation).