Because of the critical role of FOXC1 in BLBC cell function, along with an opposing expression pattern between BRCA1- and BRCA2-mutant breast cancers, it is speculated that BRCA1, not BRCA2, mutation-elicited signaling might synergize with FOXC1 action in mammary tumorigenesis. The gene discussed is BRCA1; the disease is breast carcinoma.