IDH1 and central nervous system cancer: To investigate a potential prognostic value of the IRRG signature in stratified cohorts, glioma patients were divided according to their age (≤45 or >45), gender (female or male), grade (WHO 2, 3, or 4), IDH (mutation or wild type), radiotherapy (no or yes), chemotherapy (no or yes), 1p19q (codel or noncodel), and MGMT (methylated or unmethylated) status.