OBJECTIVE: Jews drink less than other Caucasians and have a higher prevalence of ADH2*2, an allele of an alcohol dehydrogenase gene that protects against heavy drinking. The relationship of ADH2 polymorphisms to lifetime maximum number of drinks per occasion was investigated in recent Russian immigrants to Israel (exposed to heavier drinking in their country of origin), other Israeli Ashkenazis, and Sephardics. METHOD: Seventy-five randomly sampled Israelis participated in a structured interview. ADH2 was genotyped for 68 subjects. RESULTS: ADH2*2 predicted less drinking; however, associations between ADH2 and drinking appeared to differ across the groups, consistent with differences in environmental exposure to heavy drinking. CONCLUSIONS: The findings support a protective effect for ADH2*2 against heavy drinking in Jewish samples but also suggest the importance of environment. Future work should investigate interactions between genes and the environment in larger samples.