BRCA1 and neoplasm: Firstly, Molyneux et al. (2010) and Melchor et al. (2014) elegantly demonstrated that the loss of BRCA1 within luminal progenitors in mice leads to the development of basal-like tumours and subsequently, depending on the initiating genetic insult, that luminal-like, basal-like and normal-like tumours can all arise from luminal progenitors.