GLI1 and medulloblastoma: This prompted us to investigate the expression profile of the Gli1 variants in medulloblastomas from the tumor-prone Sufu+/-Trp53-/- mice maintained on a C57BL/6 genetic background (Heby-Henricson, K, Bergström, Å, Rozell, B, Toftgård, R, Teglund, S, unpublished) by using real-time RT-PCR (Figure 3C).