A brain tumor which contains isocitrate dehydrogenase (IDH) and telomerase reverse transcriptase (TERT) mutation, accompanied with 1p/19q deletion would be diagnosed as an oligodendroglioma; IDH mutation with wild TERT is a characteristic of astrocytoma (Labussiere et al., 2010; Sahm et al., 2014). The gene discussed is IDH2; the disease is brain neoplasm.