Data for the current study were derived from a multisite study of the genetics of alcohol dependence, cocaine dependence, and opioid dependence conducted through Yale University School of Medicine, the University of Connecticut Health Center, the University of Pennsylvania Perelman School of Medicine, the Medical University of South Carolina, and McLean Hospital. The sample was composed of alcohol, cocaine, or opioid-dependent individuals and unaffected controls recruited for case–control genetic studies of substance use disorders and cocaine or opioid-dependent probands and their relatives from family-based genetic studies. Subjects from the multisite study with genotypic data for rs2066702 (AA subsample) or rs1229984 (EA subsample) who reported on their exposure to adverse childhood events and had consumed at least one alcoholic drink over the lifetime were included in the present study: 2,617 African-Americans and 1,436 European-Americans. Demographic and psychiatric characteristics of the sample are shown by population in Table 1. In both AA and EA subsamples, women comprised just under half of the subjects, mean age was about 40, approximately one-third of subjects completed fewer than 12 years of education, half reported their
