Indeed, of the genes differentially expressed between IDH mutation types (with > twofold change in expression level at p < 0.01 significance level) in astrocytomas, most (157/183, 86%) were upregulated in IDH1R132H mutated tumours (Fig. 3d, Supplementary Table 4, online resource). Here, IDH2 is linked to astrocytoma (excluding glioblastoma).