KLK3 and Familial prostate cancer: Noteworthy, the association between GPRC6A gene and prostate cancer risk has been widely reported in Eastern Asian populations [43,44,45], and the rs2274911 polymorphism in GPRC6A has been associated with increased risk of prostate cancer, since this mutation promotes prostate cancer cell proliferation and is associated with increased prostate-specific antigen (PSA) serum levels [46].