STAT2 and immunodeficiency 45: The Interferon Alpha And Beta Receptor Subunit 2 gene encodes a type I membrane protein that forms one of the two chains of a receptor for interferons alpha and beta. Binding and activation of the receptor stimulates Janus protein kinases, which in turn phosphorylate several proteins including STAT1 and STAT2. IFNAR2-associated diseases include immunodeficiency 45 and measles.