CYP2D6 and breast cancer: Other genes associated with adverse drug events with potential benefits for use in clinical practice could be: CYP2D6 and tamoxifen for breast cancer, DPYD and fluoropyrimidine antimetabolite 5-fluorouracil (5-FU) for colon cancer, SLCO1B1 and Simvastatin for the reduction of cholesterol levels, HLA-A*33:03 and ticlopidine for secondary prevention of atherothrombosis [117, 120].