IDH1 and central nervous system cancer: Mutations in isocitrate dehydrogenase 1 and -2 (IDH1 and -2) genes are found in acute myeloid leukemia (~20%) [1], gliomas (60-80%) [2, 3], cholangiocarcinomas (7-28%) [4-6] and in benign and malignant cartilage tumors [7-10].