CYP2C9 and breast cancer: The frequencies of CYP2C9*2 and CYP2C9*3 reported in these publications are 5.1% for CYP2C9*2, 15.4% for CYP2C9*3 in breast cancer patients29, 4.45% for CYP2C9*2, 22.8% for CYP2C9*3 in cardiovascular patients taking warfarin31 and 12.1% for CYP2C9*2, 14.1% for CYP2C9*3 in heart valve replacement patients taking warfarin30.