Genetic testing is on the cusp of a major revolution, which has the potential to shift not just how we understand our risk for disease, but how we practice healthcare. In the clinic today, genetic testing is used only in cases where we know that mutations have big impact on physiology (BRCA mutations in breast cancer, for example). But our knowledge of how our genetics influences our risk for disease has evolved, and we now know that many (tens of thousands to even millions) small changes in our genes, each of which individually has a tiny effect, combine to influence our risk profile. This new appreciation — coupled with powerful statistical methods and massive datasets — has fueled the creation of a new tool to quantify the risk of a broad range of common diseases: the polygenic risk score. On this episode, host Lauren Richardson (@lr_bio) is joined by Dr. Peter Donnelly, (@genemodeller Professor of Statistical Science at the University of Oxford and the CEO of Genomics PLC,) and Vineeta Agarwala, (@vintweeta physician-scientist and general partner at a16z), to discuss these scores and how they can reshape healthcare, away from a paradigm of treating illness and towards prevention and maintenance of health.