Truncating mutations of MAGEL2cause Prader-Willi phenotypes and autism

Prader-Willi Syndrome (PWS) is caused by the absence of paternally expressed, maternally silenced genes at 15q11-q13. We report four individuals with truncating mutations on the paternal allele of MAGEL2 , a gene within the PWS domain. The first subject was ascertained by whole genome sequencing analysis for PWS features. Three additional subjects were identified by reviewing results of exome sequencing of 1248 cases in a clinical laboratory. All four subjects had autism spectrum disorder (ASD), intellectual disability (ID), and a varying degree of clinical and behavioral features of PWS. These findings suggest MAGEL2 is a novel gene causing complex ASDs, and MAGEL2 loss of function can contribute to several aspects of the PWS phenotype.