Similarly, the genomic distances between glioblastoma and oligodendroglioma (median JD: 0.118) and between IDH1/2-mutant astrocytoma and oligodendroglioma (median JD: 0.088) were greater than the genomic heterogeneity within each respective glioma subtype (all P < .001). Here, IDH1 is linked to astrocytoma (excluding glioblastoma).