The ZNF804A SNP association results are shown in Table 2. Rs7597593-T was the minor allele in European Americans (frequency=38.9%, similar to the 39.5% observed in Han Chinese [Sun et al., in press]) but the major allele in African Americans (frequency=63.8%). Rs1344706-A was the major allele in both the European Americans (frequency=61.1%) and African Americans (frequency=91.5%), compared to its 48.4% frequency in the Han Chinese (Sun et al., in press). Both SNPs were associated at P<0.05 in European Americans with heroin addiction cases being 1.15 and 1.14 times as likely to carry the rs7597593-T and rs1344706-A alleles, respectively, compared with controls. Neither allele was significantly associated in the African Americans. However, consistent directions of association were observed across both ancestry groups for rs1344706-A, and it was the only SNP that was significantly associated in the multiancestry meta-analysis (P=0.016).
