Vitamin C can coactivate KDM5B/C to demethylate H3K4me3, and KDM5B (JARID1B) has been shown to increase DNA DSB repair by recruiting factors Ku70 and BRCA1 in osteosarcoma (U2OS) cells (Li et al., 2014). The gene discussed is KDM5B; the disease is osteosarcoma.