In the male sample, the G allele of rs11072768 in CHRNB4 was nominally significantly associated with SI (P = 0.001; OR = 1.22; 95% CI: 1.08, 1.37), SQ (P = 0.016; OR = 1.16; 95% CI: 1.03, 1.31), and SC (P = 0.01; OR = 1.18; 95% CI: 1.04, 1.34), and rs951266 (A) in CHRNA5 and rs6495308 (T) in CHRNA3 were nominally significantly associated with SI and SQ, respectively. In addition, we found that SNPs rs4887077 (T) and rs11638372 (T) in the intergenic region downstream from the 5′ end of CHRNB4 were nominally significantly associated with SQ. Of these associations, only that of rs951266 in CHRNA5 with SQ and rs11072768 in CHRNA4 with SI remained significant after correction for multiple testing.
