The current consensus given in the last WHO classification of central nervous system (CNS) tumours from 2016 has addressed four MB molecular subgroups, termed wingless (WNT), sonic hedgehog (SHH) with or without TP53 activation, Group 3 and Group 4, which are non-WNT/non-SHH activated [3]. The gene discussed is TP53; the disease is neoplasm.