Loss of BRCA1 has been shown to expand breast stem cells. In Nature Medicine, Lim et al. (2009) demonstrate that breast tissue from BRCA1 mutation carriers contains expanded luminal progenitor cells, suggesting a broader role for BRCA1 in mammary development. © 2009 Elsevier Inc. All rights reserved.
Ginestier, C., Liu, S., & Wicha, M. S. (2009, September 4). Getting to the Root of BRCA1-Deficient Breast Cancer. Cell Stem Cell. https://doi.org/10.1016/j.stem.2009.08.007