We performed a fixed-effects meta-analysis based on the cohort's effect sizes and standard errors using METAL.36 Our meta-analysis combined association summary statistics for 6 444 471 SNPs that passed all the filters. We applied the conventional threshold of 5 × 10−8 as an indication of genome-wide significance (see ref. 37). Although the combined sample size of the meta-analysis based on the discovery samples is 32 330, the sample size per SNP varies due to missingness across subsamples.
