Using different sets of CpG methylation biomarkers from the 450K array, Paul et al. were able to classify IDH1/IDH2 mutant tumors versus IDH1/IDH2 wild-type tumors, as well as oligodendroglioma, astrocytoma, and glioblastoma [18], proving to be a powerful tool for glioma classification. The gene discussed is IDH2; the disease is glioblastoma.