Gene set enrichment analysis (GSEA) identified significantly enriched pathways (FDR < 0.05) activated or repressed in GIC (Fig. 1f) which are known to be deregulated in glioblastoma, including enrichment for neuronal system, GPCR signalling, DNA repair, extra-cellular matrix organisation, NOTCH signalling and circadian clock for genes with an activating HM in GIC (Fig. 1f and Additional File 1: Fig.S4a). Here, CLOCK is linked to glioblastoma.