The odds of developing a carcinoma within 30 wk after DMBA administration was 8.10 times higher for p19 Arf−/− mice (95% CI (1.90, 34.56); p = 0.005) and 3.11 times higher for p19 Arf+/− mice (95% CI (0.90, 10.77); p = 0.073) compared to wild-type mice. This evidence concerns the gene CDKN2A and carcinoma.