Of note, looking at methylation of all CpGs included on the methylation array, we observed a high rate of unmethylated CpG probes in ASTRO PNCs, which may indicate a more aggressive clinical course in IDH-mutant astrocytomas (G-CIMP low), comparable to IDH-wildtype glioblastomas and high-grade IDH-mutant astrocytomas (Supp. Here, IDH1 is linked to glioblastoma.