33 cytokines were significantly increased in the 75 COVID-19 patients compared with the HC group (Figure 1), including CTACK, G-CSF, GM-CSF, GRO-a, HGF, IFN-α2, IFN-γ, IL-1a, IL-1β, IL-2ra, IL-5, IL-6, IL-7, IL-8, IL-9, IL-10, IL-12(p70), IL-12(p40), IL-13, IL-15, IL-17, IL-18, IP-10, LIF, M-CSF, MIF, MIG, β-NGF, SCGF-β, SDF-1a, TNF-α, TNF-β and VEGF. The gene discussed is IL9; the disease is COVID-19.