We used genome-wide association estimates for cannabis ever use from the 2018 Pasman et al.9 meta-analysis of GWAS data from the ICC and UK Biobank for ever use of cannabis during one’s lifetime to calculate a cannabis ever use PRS for participants in COGA. We used the -score procedure in PLINK43, which computes a linear function of the number of scored alleles an individual possesses weighted by the associated GWAS beta coefficient. Matching SNPs were pruned for linkage disequilibrium (LD) based on 1000 Genome phase 3 reference panel genotype data for EA for EA participants and AA for AA participants, with clumping based on the Pasman et al. GWAS p values using a 500-kb physical distance and an LD threshold of r2 ≥ 0.25. We note that the Pasman et al. study9 is entirely of EA. Because of this, genetic influences captured in this PRS will likely predict cannabis use behavior in AA samples poorly44. Therefore, the current manuscript focuses on COGA’s EA participants. However, COGA includes one of the largest genetically informative AA samples available. We therefore conducted a
