The EGFRvIII rearrangement leads to the formation of the EGFRvIII variant: up to 70% of glioblastomas may express this EGFR variant; the presence of EGFRvIII is strongly associated with the “classical” molecular subtype of glioblastoma, where it is found in association with PTEN mutations, but it is mutually exclusive with P53 and IDH1 mutations. This evidence concerns the gene IDH1 and glioblastoma.