Tumors in the tp53-/- + TP53C176F group grew slowly and experimental animals were followed for up to 90 days, yet no medulloblastoma tumors were observed, suggesting that hypomorphic TP53P153Δ activity is likely not sufficient to initiate medulloblastoma tumors, in addition to head and neck ERMS. The gene discussed is TP53; the disease is medulloblastoma.