The Collaborative Study on the Genetics of Alcoholism (COGA) was used as the target dataset. We used the European ancestry participants from COGA for PRS analysis in order to remain consistent with the ancestry of the discovery datasets. COGA recruited alcohol dependent probands and their family members from inpatient and outpatient treatment facilities in multiple centers, as well as comparison families in the same areas (Nurnberger et al., 2004, Reich et al., 1998). This study was approved by the Institutional review boards from all centers and every participant provided informed consent. To evaluate alcohol related phenotypes, we used the Semi-Structured Assessment for the Genetics of Alcoholism interview (SSAGA, for age≥18) and the child/adolescent version of the SSAGA (for age≤17) (Bucholz et al., 1994, Hesselbrock et al., 1999). Only individuals reporting drinking at least one full drink of alcohol in their lifetime were included in analyses. AUD cases were defined as having either lifetime DSM-IV alcohol dependence or DSM-5 AUD. The controls used in this study were defined as follows: 1) 21 years or older; 2) Not meeting any criterion of
