Alcohol dependent probands were ascertained by COGA through alcohol treatment programs and evaluated at multiple centers in the US: Indiana University, State University of New York Health Science Center Brooklyn, University of Connecticut, University of Iowa, University of California-San Diego, Washington University in St. Louis, and Howard University. The Institutional Review Boards of all participating institutions approved the study. After participants provided informed consent, probands and their relatives were administered the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA, (Bucholz et al., 1994), a validated poly-diagnostic instrument. Details of ascertainment and assessment have been previously described (Nurnberger et al., 2004). In addition, community probands were recruited at each site using a variety of methods, including through driver’s license records, random mailings to employees and students at a university, and attendees at medical and dental clinics. Again, after providing informed consent, community probands and their family members were administered the SSAGA.
