Contrary to this idea, however, is the finding that p53-deficient mice lacking both CRY1 and CRY2 proteins are actually resistant to cancer and have increased lifespan, relative to p53-deficient mice, and CRY1/CRY2-deficiency promoted apoptosis following UV-irradiation [23, 51 (but see 48)]. This evidence concerns the gene TP53 and cancer.