The definition of glioblastoma now includes all astrocytic gliomas that do not have mutated IDH and H3 genes and also include one or more characteristically genetically altered profile involving TERT promoter, EGFR gene amplification, +7/−10 chromosome copy-number alterations or present themselves with necrosis or microvascular proliferation [20]. Here, IDH1 is linked to glioblastoma.