Previous studies on returning PRS to patients have produced mixed results. For example, the Genetic Counseling/Lifestyle Change (GC/LC) study, which delivered a genetic score constructed from 36 T2D-associated SNPs to overweight patients at risk for T2D, reported limited changes in lifestyles and prevention program adherence compared with controlled participants who did not receive genetic counseling [50–52]. The MedSeq Project, which returned polygenic risk estimates for cardiometabolic traits along with monogenic disease risk, pharmacogenomic associations, and family history to patients and their healthcare providers (HCPs), found that genetic testing may prompt additional clinical actions of unclear value [53]. In contrast, the MI-GENES study provided evidence that disclosure of the genetic risk of coronary heart disease led to greater statin use and lower low-density lipoprotein cholesterol levels after 6 months than returning conventional risk factors alone [54]. The different conclusions drawn from these clinical trials may be partly explained by the many factors that influence the effectiveness of returning PRS to patients, including the understanding of the implications of polygenic risk by patients and HCPs, the change of healthcare services based on
