on MAF for the five SNPs. There is a possibility that adjustment for self-reported race in the combined analysis may not be sufficient to address this confounding by race. However, in a subgroup of samples with AIMs available, the association results remained similar when using admixture proportion as a covariate, arguing against stratification as a confounder. Finally, the control samples used in the binary traits analysis include many “never-smokers” which may have become dependent if they had been exposed to nicotine, and this could arguably have reduced the power.
