The IFN system consists of a cellular mechanism to ‘sense’ infection (usually by detection of viral nucleic acids), followed by a cytokine-based (IFN) signaling cascade that confers protection to cells via transcriptional upregulation of several hundred antiviral IFN-stimulated genes (ISGs) (for several excellent and comprehensive reviews, please see [19,20,21]). This evidence concerns the gene IFNA1 and infection.