To determine whether the loss of Krt76 directly impacts tumour incidence in the oral cavity, we treated control (wild-type Krt76+/+ and heterozygous Krt76+/−) and Krt76−/− mice with a synthetic carcinogen 4NQO14 (Fig. 5a) that mimics the carcinogenic effects of tobacco and alcohol ingestion15. Here, KRT76 is linked to neoplasm.