Interferons are normally produced and secreted upon viral infection, and secreted IFN binds to the IFN receptor and activates Janus kinase 1 (JAK1) and tyrosine kinase 2 (TYK2) which phosphorylate signal transducers and activators of transcription proteins (STAT1 and STAT2) (94). This evidence concerns the gene TYK2 and viral infectious disease.