Family History, PRSs Are Independent Measures of Disease Risk

Family history and polygenic risk scores are mostly independent measures of disease susceptibility, according to a study appearing in the American Journal of Human Genetics. Researchers from the University of Helsinki and the Broad Institute used family relationship and genotyping data from more than 306,000 individuals from the FinnGen study to examine any overlap in the contributions of family history and PRSs to the susceptibility of two dozen non-communicable diseases. In their analysis, the researchers found that PRSs explain about 10 percent of the effect of first-degree family history, while first-degree family history explains about 3 percent of PRSs. Instead, PRSs and family history provide complementary data, according to the researchers. "The effects of family history and PRS were largely independent, and the pattern was observed across the diseases," the Helsinki team writes. "We demonstrate that polygenic risk and family history are not interchangeable measures of genetic susceptibility."