This IDH-mutant G-CIMP positive subtype has now been further refined into two distinct subgroups, G-CIMP-low (10% of IDH-mutant, 1p/19q intact tumor) and G-CIMP-high (90% of IDH-mutant, 1p/19q intact tumors), with ‘low’ and ‘high’ designations determined by a low or high degree of DNA methylation, respectively. Here, IDH2 is linked to neoplasm.