Comparing mice treated with DMBA 3 months after pituitary isografts, the average tumour growth rate were non-significantly different between Cre- (49±30 mm3/day) and Cre+ (81±39 mm3/day) mice suggesting that Cx26 knockout prior to mammary tumour onset did not predispose the gland to primary tumors with increased growth rate (Figure 3B). This evidence concerns the gene GJB2 and neoplasm.