The absence of any impact of RBP-J deletion on tumour formation was surprising as several studies have noted dysregulation of Notch pathway components in both human and murine medulloblastoma, including the transcription factor targets Hes1 and Hes5, and the expression of Hes1 is associated with poor clinical outcome [24,26,27,45,47]. The gene discussed is RBPJ; the disease is medulloblastoma.