Ancestry-specific hereditary cancer panel yields: Moving toward more personalized risk assessment

Abstract

Healthcare disparities in genomic medicine are well described. Despite some improvements, we continue to see fewer individuals of African American, Asian, and Hispanic ancestry undergo genetic counseling and testing compared to those of European ancestry. It is well established that variant of uncertain significance (VUS) rates are higher among non-European ancestral groups undergoing multi-gene hereditary cancer panel testing. However, pathogenic variant (PV) yields, and genomic data in general, are often reported in aggregate and derived from cohorts largely comprised of individuals of European ancestry. We performed a retrospective review of clinical and ancestral data for individuals undergoing multi-gene hereditary cancer panel testing to determine ancestry-specific PV and VUS rates. An ancestry other than European was reported in 29,042/104,851 (27.7%) of individuals. Compared to Europeans (9.4%), individuals of Middle Eastern ancestry were more likely to test positive for one or more pathogenic variants (12.1%, p = .0025), while African Americans were less likely (7.9%, p < .0001). Asian and Middle Eastern individuals were most likely (34.8% and 33.2%, respectively) to receive a report with an overall classification of VUS, while individuals of Ashkenazi Jewish and European ancestry were least likely (17.1% and 20.4%, respectively). These data suggest that in addition to higher VUS rates, there may be ancestry-specific PV yields. Providing aggregate data derived from cohorts saturated with European individuals does not adequately reflect genetic testing outcomes in minority groups, and interrogation of ancestry-specific data is a step toward a more personalized risk assessment.

Keywords: ancestry; disparities; diversity; genetic counseling; multi-gene panel testing.