SNPs were selected using a MAF range of 0.5–5% in either the EA or AA population. Missense and nonsense SNPs located within the main OPRM1 isoform (MOR-1) were prioritized for genotyping. This led to the identification of 4 SNPs for genotyping in our addicted populations: rs62638690 and rs17174794 in EA’s and rs1799971 and rs17174801 in AA’s.
