was 1.0155 (s.e. = 0.0085), indicating that the inflation was mostly due to polygenic signal and unlikely to be substantially confounded by population structure. The genome-wide significance threshold for the GWAS was set at a P value of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$5.0\times 1{0}^{-8}$$\end{document}5.0×10−8. The 23andMe data included information on the X chromosome; as this information was not present for all other cohorts, analysis of the X chromosome was only conducted in this subcohort (see Supplementary Note 4 for details).
