However, genes encoding common proinflammatory cytokines such as TNF-α, IL-1β, IL-12 (p35 and p40 genes), and IFN-γ were not observed to be expressed in any of the cell types to a significant degree and proportion, indicating that immune cells are likely the core contributors of these cytokines in COVID-19 patients. This evidence concerns the gene IFNG and COVID-19.