of affection status via the ADI-R and ADOS that could not be reconciled. We also excluded families with known chromosomal abnormalities (where karyotyping was available), and those with inconsistencies in genetic data (generating excess Mendelian segregation errors or showing genotyping failure on a test panel of 24 SNPs used to check gender and sample identity with the full array data). The self-reported race/ethnicity of these samples is 69% white, 12% Hispanic/Latino, 10% unknown, 5% mixed, 2.5% each Asian and African American, less than 1% Native Hawaiian/Pacific Islander and American Indian/Native Alaskan.