Therefore, we termed tumors that had mutations in IDH1 or IDH2 combined with either 1p/19q loss, CIC mutation, or FUBP1 mutations as “I-CF gliomas.” CIC and FUBP1 mutations were mutually exclusive with ATRX or TP53 mutations (P <0.001 for all four comparisons). Here, IDH2 is linked to central nervous system cancer.