Finally, a non-synonymous variant rs12914008 in CHRNB4, though rare in EAs (4.5%) and virtually non-polymorphic in AAs (0.6%), is nominally associated with nicotine dependence in EAs (p = 0.035, OR = 0.73 (95% CI 0.54–0.97)). Although this SNP is too rare for a meaningful test in AAs alone, the odds ratio is consistent in the two groups, and combining AAs and EAs improves the association evidence slightly (p = 0.022, OR = 0.71 (0.53–0.95)).
