The initial genome-wide meta-analysis had a few consistent findings, but the variants identified in these GWASs explained a very small proportion of heritability for alcohol related traits [28, 49, 57, 58]. A very large sample size was needed to account for the missing heritability and it was a great deal of challenge to identify the well characterized large cohorts with AUD phenotypes. To address this challenge, recent genome-wide efforts focussed on larger sample sizes assembled via consortia-led meta-analyses (Figure 1 and table 1). Researchers got access to alcohol consumption data for large number of individuals through UKBiobank and it finally provided necessary boost in gene identification efforts for alcholism. Clarke and colleagues[59] were the first group to take advantage of this cohort and reported genome-wide significant associations at 14 loci including ADH1B gene (Table 1). Soon most of these initial findings were replicated in a very large meta-analysis of alcohol consumption of over 30 datasets (UKBibank, 23andMe and other GWAS) across nearly 1.2 million participants of European ancestry (Table 1; Figure 1)[60]. In this study, Liu and colleagues discovered 566
