Alcoholic probands were recruited from inpatient and outpatient treatment facilities through six sites participating in the Collaborative Study on the Genetics of Alcoholism (COGA) (Begleiter et al., 1995; Foroud et al., 2000). The probands and their family members were administered a validated poly-diagnostic interview, the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA) (Bucholz et al., 1994; Hesselbrock et al., 1999). Individuals below the age of 18 were administered an adolescent version of the SSAGA. Institutional review boards at all sites approved the study.
