ATRX and medulloblastoma: We also point out mutations in ATRX and MLL2, two chromatin-remodelling genes, as they are frequently altered in gliomas, neuroblastomas, medulloblastomas and neuroendocrine tumours28, 29, 30, 36, 37, 38, 39, 40 and may therefore constitute a converging tumorigenic pathway for these related tumour types.