In contrast, cluster ST11 shows gene set enrichment of pathways related to intracellular pathogen signaling (NOD-like and RIG-I-like receptor pathways), complement and coagulation cascades, and KEGG-terms associated with viral infections such as COVID-19 and hepatitis C. Moreover, most upregulated genes in cluster ST11 are interferon-stimulated genes (ISGs), including Ifit1, Ifih1, Irf7, and Irf9 (Fig. 1c, Supplementary Fig. 5, and Supplementary Data 1). The gene discussed is IRF9; the disease is COVID-19.