Finally, we combined our chr15q25.1 results with data from three other published reports (Table S3) [44], [46], [47]. The SNP rs1051730, found within CHRNA3 (Ex5+268), was highly statistically significantly associated with CPD (p = 5×10−32); the SNP rs8034191 (LOC123688 IVS2+256) was also highly statistically significantly associated with CPD (p = 2×10−29). These SNPs were evaluated using a total of 26,789 (rs1051730) or 24,891 (rs8034191) smokers from this study and two other reports. The CHRNA5 SNP rs16969968 (Ex5-54, D398N) was significantly associated (p<.01) with CPD in this study but not an earlier, smaller study; combined evidence for association in 3,464 smokers remained significant (p = 2×10−3). Comparative judgments of the relative importance of the individual SNPs are not possible due to the different sample sizes, the strong LD among the SNPs and the inability to adjust for the effects of the other SNPs in this meta-analysis.
