We next asked if the variants tested in the follow-up samples were, in aggregate, consistent with the presence of additional sub genome-wide significant BD association signals. After excluding 47 variants that were genome-wide significant in our GWAS, our combined analysis or previous BD GWAS, 775 variants remained in our follow-up experiment. 551 variants had the same direction of effect in the discovery GWAS and follow-up (71%, compared to a null expectation of 50%, sign test p = 1.3×10−32), and 110 variants had the same direction of effect and were nominally significant (p<0.05) in the follow-up (14%, compared to an expected value of 5%, binomial test p = 2.1×10−22). This consistency between our GWAS and follow-up results suggests that many more true BD associations exist among these variants.
