To examine the utility of BarTeL mice in producing medulloblastomas modeling the SHH subgroup, we injected cerebella of BarTeL pups at 1–3 days of age with nontumorigenic chicken DF-1 cells producing either RCAS-ShhN or RCAS-MycnT50A,S54A, or with DF-1 cells producing both viruses. The gene discussed is SHH; the disease is medulloblastoma.