BRCA1 and breast cancer: We previously demonstrated that mice with mammary gland (MG)‐specific deletion of Brca1 exon 11 (Brca1flox/flox; MMTV‐Cre) spontaneously developed mammary tumors.[qv: 17] To explore the function of BRCA1 in cytoplasm, we carried out a genome‐wide unbiased approach to analyze gene expression by RNA sequencing (RNA‐Seq) in both Brca1 mutant (MT) and wild‐type (WT) MGs from Brca1flox/flox; MMTV‐Cre, and Brca1flox/flox mice, respectively.