Therefore, according to these studies two major genetic subtypes of IDH-mutant gliomas have been identified: one is defined by TP53 and ATRX mutations and correlated with astrocytic morphology; the other one is characterized by concurrent mutations of CIC, FUBP1, and TERT promoter and association with oligodendroglioma histology. The gene discussed is IDH1; the disease is oligodendroglioma.