In summary, the empirical data provide some evidence that the Asn40Asp SNP is associated with a differential subjective response to alcohol and as a predictor of clinical response to naltrexone. These findings have been met with considerable enthusiasm as well as a healthy level of skepticism. As stated by O’Brien (2008), if supported, “the results of such pharmacogenetic studies could change clinical practice so that the selection of medication could be based on genotype rather than guesswork” (p. 133). Personalized medicine is the ultimate goal of pharmacogenetic studies, and the field of alcoholism has received attention for its strong efforts toward personalized care (Kranzler and Edenberg, 2010; Kuehn, 2009). It appears that considerable work remains to be performed before the promise of targeted therapies may be realized for naltrexone. Nevertheless, the biological and clinical plausibility of this line of research is rather compelling in the case of naltrexone and the Asn40Asp SNP of OPRM1. A summary of the human studies of OPRM1 and alcoholism phenotypes is presented in Table 1.
