We evaluated 22 SNPs in the CHRNA5/A3/B4 cluster in two independent ethnic samples. Association of individual SNPs with the three ND measures was determined with the PBAT-GEE program (Lange and others 2003), and the results are shown in Table 2. For CHRNA3, we found marginal associations for rs1317286 with SQ and HSI (P = 0.02 and 0.05, respectively) and of rs8040868 with SQ (P = 0.019) in the combined sample. These findings were not significant after correction for multiple testing. As for CHRNA5 and CHRNB4, no significant association was detected for any individual SNP.
