This is an Individual National Research Service Award, which provides postdoctoral research training to individuals to broaden their scientific background and extend their potential for research in specified health-related areas. The heritability of ASD and related neurodevelopmental disorders is high, but contributing genetic risk factors remain uncertain. This project aims to gain a better understanding of the impact of genomic rearrangements on neurodevelopmental abnormalities. The studies proposed will use "next- generation" sequencing to identify genes disrupted by apparently balanced rearrangements. Precise breakpoints in ASD patients with known genomic rearrangements will be mapped, then a comprehensive molecular analysis of disrupted gene(s) and pathways will be conducted. Finally, a large independent cohort of patients diagnosed with ASD and other disorders will be screened to identify consistent rearrangements and/or novel rare mutations.