determined. In this manuscript, we will review the relevant literature investigating the role of this SNP in human disease and treatment response, molecular and cellular function, and animal models that may help explain these effects. Indeed, several comprehensive reviews describe the role of pharmacogenetics, including OPRM1 and other genes, in specific disease states and treatment responses, such as alcoholism/addiction (Dick and Foroud, 2003; Enoch, 2003; Haile et al., 2008; LaForge et al., 2000; Oroszi and Goldman, 2004; Oslin et al., 2006) and pain (Kosarac et al., 2009; Lotsch et al., 2004; Skorpen et al., 2008); therefore, in this review we focus on the elucidation of the functional significance of the A118G SNP in disease states both in humans and animal models.
