discover variants associated with individual alcohol dependence criteria, criterion‐count based severity, 44 subjective ratings of ethanol, 45 drug dependence, 46 maximum drinks, 47 as well as brain function phenotypes. We have also utilized polygenic scores (PGS, or polygenic risk scores, PRS) extensively in COGA. Integrated with both our behavioral/clinical and brain function data, PGS data in COGA have uncovered the importance of genetic susceptibility in longitudinal pathways of alcohol involvement, internalizing and externalizing phenotypes, as well as novel neural synchrony measures (e.g., References 38, 48, 49). In addition, the family structure of COGA data have allowed the investigation of social genetic mechanisms, such as assortative mating and cultural transmission, 50 , 51 , 52 which were recently identified as confounds in standard large‐scale GWAS. 53 , 54 COGA has also contributed to a small but steadily increasing number of genetic discoveries in individuals of African ancestry. These data have allowed us to contribute to GWAS meta‐analyses, PGS analyses that utilize emerging cross‐ancestry methods, and locus discovery using admixture mapping (e.g., References 5, 44, 55). A detailed outline of these findings is available in the accompanying review (4. Genetics).
