BRCA1 showed a higher mutation rate in HR− /HER2-zero breast cancer than that in HR−/HER2-low tumors, but without significant difference in both databases, which might suggest that HR−/HER2-zero breast cancer might be a more typical TNBC subtype than HR−/HER2-low tumors [18]. The gene discussed is ERBB2; the disease is breast carcinoma.