IDH1 and glioma: Finally, a comprehensive analysis of these classifications defined three subgroups of IDH mutant gliomas (G-CIMP high—LGm1, G-CIMP low—LGm 2, and 1p19q codeleted—LGm 3) and four subgroups of IDH wild-type gliomas (classical-like—LGm4, mesenchymal-like—LGm5, and two rare subtypes—LGm6-GBM and PA-like), closely associated with transcriptional subtypes [15].