In line with this, telomerase abrogation in the context of cancer-prone mouse models, including the K-Ras+/G12D lung tumorigenesis mouse model, only showed anti-tumorigenic activity after several mouse generations in the absence of telomerase when telomeres reached a critically short length (Chin et al, 1999; Greenberg et al, 1999; Gonzalez-Suarez et al, 2000; Perera et al, 2008). This evidence concerns the gene KRAS and cancer.