While tumours readily develop in mice following DMBA/TPA treatment, conditional deletion of floxed Grhl3 in the differentiated cell-rich suprabasal epidermis using a tamoxifen-inducible Cre recombinase, driven by the IVL promoter (IVL–Cre–ERT2), confers an increased susceptibility to tumour formation similar to that seen with K14Cre Grhl3 cKO mice. The gene discussed is GRHL3; the disease is neoplasm.