Loss of G-CIMP at recurrence resembled genome-wide 5-mC patterns seen in IDH1 wild-type primary GBM, and was associated with poorer outcomes (41). A novel 7-CpG signature has been identified in non-G-CIMP primary GBMs, where high-risk signatures correlated with poorer overall survival in patients treated with temozolomide and radiation (43), suggesting that even in the absence of G-CIMP and IDH1 mutations, 5-mC marks may be prognostic. The gene discussed is IDH1; the disease is glioblastoma.