We carried out a GWA meta-analysis of a total of 32,387 individuals of European ancestry from 15 cohorts of 1,094 to 5,433 individuals using two parallel analytic strategies (Supplementary Fig. 1 and Supplementary Tables 1–3 online). First, we carried out a weighted z-score–based meta-analysis combining P values from cohort-specific analysis strategies. Second, we also performed an inverse-variance meta-analysis using regression coefficients and their standard errors obtained by applying a uniform analysis strategy across all studies. The results for these two strategies were highly congruent (Supplementary Fig. 2 online). Here we report results of the weighted P value analysis, as it was completed first and used to select SNPs for follow-up genotyping.
