PRS was conducted using PLINK18, 30 for the three major adult psychiatric disorders (schizophrenia (SCZ),16 bipolar disorder (BIP)31 and major depressive disorder (MDD)32) for which GWAS results from large studies are publicly available. SNP-level summary statistics from each of the three ‘discovery’ disorders were used to create the ‘score’ files. Each individual in this study was scored for genetic risk by weighting risk alleles according to the natural log of the odds ratio (OR) from each of the discovery disorder meta-analyses. The following commands were used: to specify the bed/bim/fam fileset from this study to be scored (—bfile), specify the file with logORs (—score), stop the default behavior of mean imputation (no-mean-imputation), specify the file with P-values from the discovery disorder (—q-score-file) and provide specified ranges of P-values to be scored (—q-score-range). See Supplementary Table S2 for 38 P-value bins (12 bins per disorder plus one additional bin for genome-wide significant loci for both SCZ and BIP). After scoring, the significance and magnitude of polygenic PTSD prediction was calculated for each of the 38 P-value bins. Two logistic regressions were
