Among the few consistent findings from gene discovery studies of alcohol phenotypes is the association of ADH1B, which encodes alcohol dehydrogenase 1B, a key enzyme in alcohol metabolism, with liability to heavy alcohol consumption and alcohol dependence. The single nucleotide polymorphism (SNP) rs1229984*G to A encodes an arginine to histidine substitution, (Hurley and Edenberg, 2012), increasing the clearance of alcohol. This effect, presumably through increased acetaldehyde concentrations, protects against alcohol misuse. The protective effect of the His allele has been well documented in Asian populations (Kim et al., 2008, Li et al., 2011, Park et al., 2013), in which the prevalence is approximately 70% (Li et al., 2011). It has also been found in Israeli Jews, 20–40% of whom carry the A allele (Carr et al., 2002, Meyers et al., 2013a, Neumark et al., 2004). Although the His allele is far less prevalent in European populations (under 4%, Hurley and Edenberg, 2012), large-scale studies have demonstrated that A-allele carriers of European descent also exhibit lower levels of heavy and problem drinking (Bierut et al., 2012, Gelernter et al., 2014, Tolstrup
