The Collaborative Study on the Genetics of Alcoholism (COGA) is a large family-based sample enriched for alcohol and other substance use disorders34. COGA recruited alcohol-dependent probands from inpatient and outpatient AUD treatment facilities and comparison subjects from the same communities. Probands and their family members were interviewed with the Semi Structured Assessment of Alcoholism (SSAGA35,36). Informed consent was obtained from all participants and institutional review boards at all sites approved the study. For further details, see ref. 34. The primary analytic sample included 7591 individuals of EA, because the GWAS from which PRS was calculated was based on EA. Secondary analyses included 3359 individuals of African ancestry (AA). A description of the analytic sample, including self-reported “race/ethnicity” (correlation with genetic ancestry = 0.95, p < 0.001) is in Table 1.Table 1Description of the analytic sample, a subset of the Collaborative Study on the Genetics of AlcoholismAll participants (N: 10,954)European ancestry (N: 7599)African ancestry (N: 3355)Female580539981807Age at most recent interviewRange: 12–91 years; M: 35.61 (SD: 14.18)Range: 12–91 years; M: 36.77 (SD: 14.83)Range: 12–84 years; M: 32.88 (SD: 12.16)Self-reported race White/Caucasian76557454201 Black/African
