O6-methylguanine DNA methyltransferase(MGMT) promoter methylation and IDH1 mutation were recently identifiedas molecular biomarkers for GBM, now regarded as favorable prognosticindicators for overall survival.67,68 IDH1 mutationis an exclusion criterion to call a malignant glioma a glioblastomaaccording to the WHO 2021 criteria. The gene discussed is IDH1; the disease is glioblastoma.