OAS2 (2'-5'-Oligoadenylate Synthetase 2) is a Protein Coding gene. The OAS2 gene, located on 12q24.13, is conserved in chimpanzee, Rhesus monkey, dog, cow, mouse, and rat. OAS2 has been known as an antiviral interferon-stimulated gene (ISG). This gene encodes a member of the 2-5A synthetase family, essential proteins involved in the innate immune response to viral infection. The encoded protein is induced by interferons and uses adenosine triphosphate in 2'-specific nucleotidyl transfer reactions to synthesize 2',5'-oligoadenylates (2-5As). These molecules activate latent RNase L, which results in viral RNA degradation and the inhibition of viral replication. The three known members of this gene family are located in a cluster on chromosome 12. Alternatively, spliced transcript variants encoding different isoforms have been described. Diseases associated with OAS2 include Tick-Borne Encephalitis and Microphthalmia With Limb Anomalies.