Chromosomal copy number analysis of the 9 de novo RRD glioblastomas revealed an absence of the combined trisomy/gain of chromosome 7 and monosomy/loss of chromosome 10 that is typical of conventional glioblastoma, IDH-wildtype (Fig. 3, Supplementary Fig. S2, Supplementary Table S4). This evidence concerns the gene IDH2 and glioblastoma.