OPRM1 and opioid use disorder: CYP2D6 does not play a role in metabolizing buprenorphine, the primary medication used for opioid use disorder treatment at the Center for Healing at Cooper University Health Care; however, given the moderate CPIC cited evidence for variation in the OPRM1 gene playing a role in buprenorphine [15,20,25], we explored the relationship between rs1799971 and baseline buprenorphine dosing (mg/day).