Data were collected as part of the evaluation of the SAAF family-based preventive intervention study and subsequent follow-up evaluations. Participants resided in nine rural counties in Georgia. In these counties, families live in small towns and communities in which poverty rates are among the highest in the U.S. and unemployment rates are above the national average (Proctor & Dalaker, 2003). In the current study, the analytic sample was drawn from a larger, ongoing data collection (see Brody et al., 2006, for a full description). Due to budgetary constraints, we selected a subsample for biological assessment (N = 399), and these participants provided blood draws allowing us to conduct methylation analyses. The sample eligible for the current study included the 388 families randomly assigned to SAAF or control who participated in the blood draw, completed data on all measures, and were successfully genotyped at 5-HTTLPR. Target youth mean age was 11.7 years at the first assessment, 13.2 at the assessment of substance use initiation, 15.6 years at the time of genotyping base on Oragene collection, and 20.5 years at the time
