Nelson et al. also performed a GWAS focused exclusively on opioid-exposed individuals, comparing daily injection opioid users in an Australian cohort to individuals who abused opioids but never injected daily (case n =1167, control n = 161) [41*]. A variant in CNIH3 (Cornichon Family AMPA Receptor Auxiliary Protein 3) reached genome-wide significance (rs1436175, p = 2.72 × 10−8). Other polymorphisms in the gene were also nominally significant, further suggesting that a true association signal might be coming from this locus. Meta-analysis of these CNIH3 variants in the discovery cohort and two independent populations resulted in five variants reaching genome-wide significance (rs10799590, rs12130499, rs298733, rs1436171, and rs1369846).
