One of the subgroups proposed is the so-called basal-like group of tumours, which are associated with breast cancers that express neither oestrogen receptor (ER) nor human epidermal growth factor receptor (HER)2, but express frequently 'basal' cytokeratins (CKs) such as CK-5/6, CK-14 and CK-17. The gene discussed is KRT14; the disease is breast cancer.