PGSs have become an important tool in understanding complex genetic phenotypes and for precision medicine. Consistent with prior reports,13 we found each cannabis phenotype PGS to be significantly associated with BIP and SCZ diagnosis. A multi-PGS approach provided a statistically significant improvement in prediction of BIP and SCZ by adding PGSs for cannabis phenotypes. These findings support the idea that incorporating additional PGSs alongside the psychotic-specific PGS improves prediction accuracy.21,43 However, the improvement of our multi-PGS models were small, which limits their clinical utility. Still, the potential of these models for risk stratification of patients is promising and may become useful with larger GWAS in the future.
