IDH1 and diffuse midline glioma: Furthermore, grade IV paediatric HGGs are now classified as one of the following based on IDH status and histone 3 (H3) status: diffuse paediatric-type HGG IDH-wildtype and H3-wildtype, diffuse midline glioma (DMG) H3K27-altered, diffuse hemispheric glioma H3G34-mutant, or infant-type hemispheric glioma.1 Although the term paediatric glioblastoma is no longer applicable based on this classification system, we will use the term paediatric glioblastoma in this review where the original research work cited used the term to describe non-DMG grade IV paediatric gliomas.