Three medications are licensed in the USA for treatment of alcoholism: disulfiram (antabuse) since the 1940’s, naltrexone since 1995, and acamprosate since 2004. Disulfiram is rarely prescribed since it has potentially serious side effects and acamprosate is largely used in Europe. Naltrexone, a μ opioid receptor antagonist, has been shown to have a modest effect on drinking outcomes (reviewed in Enoch,, 201464). Genetic studies have shown that the largest therapeutic response is found in A118G G allele carriers of the OPRM1 gene. Since the frequency of the minor G allele varies markedly across ethnicity, ethnic group status is a predictor for naltrexone treatment response. G allele frequency data from HapMap shows that Japanese (0.49) and Chinese (0.36) individuals with AUD are likely to derive the most benefit from naltrexone since the G allele is common in these populations whereas the G allele is less common in European ancestry (0.17) and virtually absent in individuals of African ancestry (0.01). There are no AI/AN genotypes available in HapMap or the 1000 Genomes databases. Unpublished data from our laboratory shows that the G
