Around 50%–80% of GBM cells expressed OLIG2, and 10% expressed GFAP (Fig. S1G), indicating OPC features for most GBM cells, aligning with cellular properties observed in OPC-like GBMs (Liu et al., 2011; Wang et al., 2020; Yu et al., 2020). The gene discussed is GFAP; the disease is glioblastoma.