To examine whether expression of CDK2-activated EZH2 in mammary glands contributes to basal-like mammary tumor development, we established a transgenic mouse model expressing phospho-mimicking EZH2T416D mutant (Tg-EZH2T416D) or wild-type EZH2 (Tg-EZH2WT) driven by the mouse mammary tumor virus (MMTV) promoter. This evidence concerns the gene EZH2 and breast cancer.