Human complex traits and diseases are influenced by hundreds or thousands of genetic variants, each explaining a small proportion of phenotypic variation. Polygenic risk scores (PRS) aggregate genetic effects across the genome to measure the overall genetic liability to a trait or disease. PRS are not useful as a stand-alone diagnostic tool; rather, they have shown promise in predicting individualized disease risk and trajectories, stratifying patient groups, informing preventive, diagnostic and therapeutic strategies, and improving biomedical and health outcomes1–6.
