The features of IDH-mutant glioblastoma include mutation of ATRX (alpha-thalassemia/mental retardation, X-linked), TP53, DH1/IDH2, and PDGFRA (platelet-derived growth factor receptor alpha) amplification, and loss of heterozygosity for 10q and 19q [2]. The gene discussed is IDH2; the disease is Intellectual disability.