We found that the percentage of cells positive for G2-distinctive pH3 foci pattern was significantly increased in Trf1Δ/ΔK-Ras+/G12Vp53−/− carcinoma lesions compared to Trf1+/+K-Ras+/G12Vp53−/− lesions (Fig4B), suggestive of increased G2 arrest. The gene discussed is KRAS; the disease is carcinoma.