The levels of the following three molecules were significantly increased in gliomas with a mutant IDH compared with that observed in the wild-type IDH gliomas: citric acid (1.43-fold, p = 0.0114, Q = 0.0447), isocitric acid (1.42-fold, p = 0.0130, Q = 0.0447), and lactic acid (1.18-fold, p = 0.0312, Q = 0.0717) (Table 3; Fig. 1c). The gene discussed is IDH2; the disease is glioma.