An increased expression of EGFR in basal cells was previously observed in murine MECs [25] and hMECs [26], and a drift toward high EGFR expression was seen in cell line models of basaloid breast cancer [27], which led us to examine whether the EGFR levels differed between stem and non-stem cells as defined by the expression of ALDH1 [28,29]. The gene discussed is ALDH1A1; the disease is breast cancer.