Comparing the chromatin status between proliferating or non-proliferating IDH-mutant glioma cells with mature oligodendrocytes, marker of mature oligodendrocytes (GALC), myelin components (MAG, MBP, and MOG), and myelination-regulating transcription factors (MYRF and SOX10) showed inaccessible chromatin (Fig. 7B), whereas regulators of OPC specification and maintenance (ASCL1, CSPG4, MYT1 and PTPRZ1), inhibitor of OPC differentiation or OL lineage terminal differentiation (ID4), and COP marker (NEU4) showed open chromatin (Fig. 7C). The gene discussed is IDH1; the disease is glioma.