In 12 GWASs of alcohol dependence (most of which used a binary DSM-IV diagnosis3) published between 2009 and 2014 (ref. 12), the only consistent genome-wide significant (GWS) findings were for SNPs in genes encoding the alcohol metabolizing enzymes. Similarly, in a recent meta-analysis of 14,904 individuals with alcohol dependence and 37,944 controls, which was stratified by genetic ancestry (European, N = 46,568; African; N = 6280), the only GWS findings were two independent ADH1B variants. In addition, there were significant genetic correlations seen with 17 phenotypes, including psychiatric (e.g., schizophrenia, depression), substance use (e.g., smoking and cannabis use), social (e.g., socio-economic deprivation), and behavioral (e.g., educational attainment) traits13.
