BRCA1 and breast cancer: To address this, two BRCA1 conditional knockout mice models (WAP-Cre; BRCA1KO/CO and MMTV-Cre; BRCA1KO/CO) were developed as reported in our previous study.18 Mammary tumor formation in WAP-Cre; BRCA1KO/CO was confirmed by NMR bio imager.