DSM-IV alcohol dependence (AD), which in DSM-5 is the more severe type of AUD, is moderately heritable; genomewide association studies (GWAS) of AD and habitual alcohol use have been conducted in European (2–8), African (2, 5, 6), and East Asian (6, 9–13) ancestry populations. Most studies of AD diagnosis have been in small samples, but one reported on ~16,000 subjects (2), and the Psychiatric Genomics Consortium has completed a mega-analysis for AD (14). This AD mega-analysis included 14,904 AD cases and 37,944 controls from 28 case-control and family-based studies. Although this study consistently detected AD polygenic architecture, ADH1B risk alleles were the only loci identified, perhaps due to the heterogeneity across the cohorts included (14). Alcohol consumption is the major risk factor for AD and has medical importance per se. For example, alcohol consumption, even in the normal range (“social” drinking) bears a direct relationship to decline in several cognitive measures (15). Studies of large database samples, including the UK Biobank (4), have focused on alcohol consumption and their findings have implications for AD risk. Associations with variants mapped to
