Interferon-γ (IFN-γ) outstands one of the major proinflammatory cytokines in sepsis, as IFN-γ– or T cell–deficient mice are tolerant to polymicrobial sepsis and Escherichia coli (E. coli) infections, and neutralization of IFN-γ recovers mice from endotoxic shock (6, 7). The gene discussed is IFNG; the disease is infection.