High levels of activated c-Src in DCIS was associated with HER2 positivity (P<0.0005), high tumour nuclear grade (P<0.0005), the presence of comedo necrosis (P=0.001) and high Ki67 scores (P=0.025), but not with ER status (P=0.973), tumour size (P=0.403) and EGFR/HER1 expression (P=0.507). The gene discussed is ERBB2; the disease is ductal breast carcinoma in situ.