IFNG and COVID-19: Studies have shown abnormal levels of cytokines and chemokines in patients with COVID-19 such as IL-1, IL-2, IL-4, IL-6, IL-7, IL-10, IL-12, IL-13, IL-17, M-CSF, G-CSF, GM-CSF, IP-10, IFN-γ, MCP-1, MIP 1-α, hepatocyte growth factor (HGF), TNF-α, and vascular endothelial growth factor (VEGF) (Costela-Ruiz et al., 2020).