Luminal progenitors are expanded in BRCA1 mutation carriers and linked to basal-like breast cancers, whereas stem- and progenitor-enriched basal cells are associated with claudin-low breast cancers (Lim et al., 2009; Molyneux et al., 2010; Shehata et al., 2012). This evidence concerns the gene BRCA1 and breast carcinoma.