A study of six CHRNA4 SNPs in European Americans (EA) and African Americans (AA) reported various nominally significant findings for specific phenotypes or samples, with rs2236196 highlighted in AA women after correction for multiple testing (Li et al., 2005). Our current study provides some support for rs2236196 (p = 0.0048), although we see a stronger association with nicotine dependence at rs2273504 (p = 0.0023). Importantly, these two SNPs are uncorrelated (r2 = 0.07), indicating that we have modest evidence for potentially two distinct loci affecting nicotine dependence risk, one which is novel and the other which replicates the earlier finding in (Li et al., 2005).
