Details of the GWAS meta-analysis are outlined in Extended Data Fig. 1. All participants in all cohorts in this study gave written informed consent and sites involved obtained approval from local research ethics committees or Institutional Review Boards. The ENIGMA consortium follows a rolling meta-analysis framework for incorporating sites into the analysis. The discovery sample comprises studies of European ancestry (Extended Data Fig. 2) that contributed GWAS summary statistics for the purpose of this analysis on or before 1 October 2013. The deadline for discovery samples to upload their data was made before inspecting the data and was not influenced by the results of the analyses. The meta-analysed results from discovery cohorts were carried forward for secondary analyses and functional validation studies. Additional samples of European ancestry were gathered to provide in silico or single genotype replication of the strongest associations as part of the replication sample. A generalization sample of sites with non-European ancestry was used to examine the effects across ethnicities. In all, data were contributed from 50 cohorts, each of which is detailed in Supplementary Tables 1–3.
