IFNG and COVID-19: An exaggerated inflammatory response, deregulated host immune systems, and abnormal levels of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-1 (IL-1), interferon-gamma (IFN-γ), monocyte chemoattractant protein-1 (MCP-1), granulocyte colony-stimulating factor (G-CSF), and granulocyte–macrophage colony-stimulating factor (GM-CSF), are responsible for pathogenicity and the severity of COVID-19 [12].