We ascertained autism patients and their affected and unaffected family members as part of the Collaborative Autism Project (CAP) through four clinical groups at the Miami institute for Human Genomics (MIHG, Miami, Florida), University of South Carolina (Columbia, South Carolina), W.S. Hall Psychiatric Institute (Columbia, South Carolina) and Vanderbilt Center for Human Genetics Research (Vanderbilt University, Nashville, Tennessee) Participating families were enrolled through a multi-site study of autism genetics and recruited via support groups, advertisements, and clinical and educational settings. All participants and families were ascertained using a standard protocol. These protocols were approved by appropriate Institutional Review Boards. Written informed consent was obtained from parents as well as from minors who were able to give informed consent; in individuals unable to give assent due to age or developmental problems, assent was obtained whenever possible.
