The remaining case was originally classified as a mixed oligo-astrocytoma, which, by virtue of the presence of IDH1_R132 and TERT promoter mutation (C228T), as well as copy-number loss of chromosomes 1p and 19q, would be described as an oligodendroglioma according to WHO 2016 (Figure S3B). Here, IDH1 is linked to oligodendroglioma.