Numerous studies have reported elevated levels of IFN-γ in patients with COVID-19.9,130,131 Of note, one study showed that IFN-γ produced by CD4+ T cells was decreased in patients with severe disease compared to those with moderate disease, which could be explained by the reduced numbers and functional exhaustion of T cells in severe COVID-19,132 as described– above. The gene discussed is IFNG; the disease is COVID-19.