IDH1 and central nervous system cancer: As gliomas are a molecularly heterogeneous group, we narrowed down our analysis to molecularly similar diffuse gliomas: We analyzed IDH-mutant 1p/19q co-deleted ATRX-wt WHO grade-II and IDH-mutant 1p/19q-intact ATRX-mut WHO grade-II DGs, separately, and looked for possible associations between molecular alterations and the rs55705857 genotype.