–9 In LGGs, IDH1/2 wild-types are characterized by poor, GBM-like prognosis, while the codeletion status of 1p and 19q chromosomes and G-CIMP subtypes offer additional stratification of the LGG IDH1/2 mutant and 1p/19q intact LGGs.7 Here, IDH1 is linked to glioblastoma.