Multi-Ancestry PRS Stratifies Women Based on Breast Cancer Risk

Researchers have developed a multi-ancestry polygenic risk score to stratify women based on their breast cancer risk. Previous polygenic risk scores have largely been developed using data from individuals of European ancestry and generally do not perform as well among women from other ancestral backgrounds. Researchers from Myriad Genetics and elsewhere report in JCO Precision Oncology that they developed a PRS that incorporates genetic ancestry. They first developed separate PRSs for breast cancer risk based for three different reference ancestry populations — African, East Asian, and European — before combining them into an MA-PRS that encompasses 93 breast cancer-associated SNPs and 56 ancestry markers. Women in the top decile of risk, as determined by the MA-PRS, had similar breast cancer risk as women with moderate penetrance risk genes, the researchers note. "Overall, the MA-PRS model described here is an important step forward in the accurate prediction of BC risk in the contemporary US population, irrespective of genetic ancestry and without requiring potentially biased or inaccurate self- or health care provider–reported ancestry," they add.