Literature search was done by PubMed7 using the key words “breast cancer polymorphism phase I,” “breast cancer polymorphism phase II,” “breast cancer polymorphism CYP” “breast cancer polymorphism UGT,” “breast cancer polymorphism SULT,” “breast cancer polymorphism GST,” and “breast cancer polymorphism NAT” in August 2012. This evidence concerns the gene SLC35A2 and breast cancer.