IDH1 and glioblastoma: Then, we analyzed the R132H site of the IDH1 gene, which showed the highest rate of incidence, in the ectoderm group, and found that this point mutation mainly occurred in the glioma cases, including 358 cases of brain lower-grade glioma (LGG) and 23 cases of glioblastoma multiforme (GBM) (Fig. 5d).