STUB1 and COVID-19: However, interestingly, a subset of hypo-DMRs linked to CHIP (+) severe COVID-19 upregulated genes (Supplementary Fig. 7b) was also significantly co-occupied by H3K4me1 and H3K4me3 peaks compared to the unlinked hypo-DMRs (Fisher’s exact test, P < 0.001, H3K4me1; P < 0.001, H3K4me3) (Fig. 5c, d).