In contrast, when spleens were enlarged, we did not observe a significant difference in the proportion of cells in S-phase between hTS/Ink4a/Arf−/− and Ink4a/Arf−/− mice (28.86% vs 30.44%, n = 2 and 3, respectively), indicating that TYMS accelerates early tumor progression. The gene discussed is CDKN2A; the disease is neoplasm.