size greater than half of the maximum sample size across all the SNPs in the GWAS. In total, 9,284,738 SNPs were analyzed in the discovery GWAS of general risk tolerance; 9,339,358 SNPs were analyzed in the GWAS of adventurousness; and ~11,515,000 SNPS were analyzed in the GWAS of the four risky behaviors and their first PC. To adjust standard errors for the possible effects of population stratification, we inflated them by the square root of the estimated intercept from an LD Score regression12 (for the replication GWAS of general risk tolerance, which meta-analyzed different cohorts, we inflated them at the meta-analysis level). Additional details are provided in the Supplementary Note and Supplementary Tables 2 and 24–26.
