A subset of high-grade gliomas also exhibited this pattern: 27% (17/63) of IDH-wt GBM, 50% (3/6) of IDH-mutant astrocytomas (grade 4), 40% (2/5) of IDH-mutant astrocytomas (grade 3), 59% (10/17) of IDH-mutant 1p/19q codeleted OG (grade 3), 11% (1/9) of H3K27-altered midline gliomas, 38% (3/8) of wt high-grade pediatric gliomas, and in the only case of hemispheric G34-mutant high-grade pediatric glioma. Here, IDH1 is linked to astrocytoma (excluding glioblastoma).