Given the limited number of non-EA subjects in the sample, and that self-defined ethnicity carries non-genetic as well as genetic differences, we focused our primary analyses on the larger EA subsample. Logistic regression covarying for gender was employed to test for the association of each SNP with alcohol dependence, using an additive model. Odds ratios and p-values were computed to assess the strength of the association. All analyses were performed using PLINK (Purcell et al., 2007).
