Hyperglycemia plays an important role in the pathogenesis of T2DM, making patients more vulnerable to COVID-19 [228], since it can influence the expression of enzymes that favor the infection and replication of SARS-CoV-2 [229], as well as promoting the exacerbation of the inflammatory response through the production of proinflammatory cytokines (TNF-α, IL-1β, and IL-6) and the dysfunction of immune cells during the comorbidity of T2DM and COVID-19 [230,231,232]. The gene discussed is TNF; the disease is Hyperglycemia.