IDH2 and glioma: IDH1 is involved in the process of cell metabolism.14 Studies show that IDH1/2 gene mutation is an early event in the occurrence and development of glioma, 60-90% of IDH1 gene mutations occur in low-grade glioma.14,15 Watanabe et al16 analyzed glioma samples from patients with TP53 germline mutation syndrome and found that IDH1 mutation was R132C substitution, indicating that IDH mutation may precede TP53 mutation in the development process of glioma.