Hormone involved in the regulation of erythrocyte proliferation and differentiation and the maintenance of a physiological level of circulating erythrocyte mass. Binds to EPOR leading to EPOR dimerization and JAK2 activation thereby activating specific downstream effectors, including STAT1 and STAT3. Produced by kidney or liver of adult mammals and by liver of fetal or neonatal mammals. Disease susceptibility is associated with variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Used for the treatment of anemia. Available under the names Epogen (Amgen), Epogin (Chugai), Epomax (Elanex), Eprex (Janssen-Cilag), NeoRecormon or Recormon (Roche), Dynepo (Shire Pharmaceuticals) and Procrit (Ortho Biotech). Variations in the glycosylation pattern of EPO distinguishes these products. Epogen, Epogin, Eprex and Procrit are generically known as epoetin alfa, NeoRecormon and Recormon as epoetin beta, Dynepo as epoetin delta and Epomax as epoetin omega. Epoetin zeta is the name used for some 'biosimilars' forms of epoetin alfa and is available under the names Silapo (Stada) and Retacrit (Hospira). Darbepoetin alfa is a form created by 5 substitutions (Asn-57, Thr-59, Val-114, Asn-115 and Thr-117) that create 2 new N-glycosylation sites. It has a longer circulating half-life in vivo. It is available under the name Aranesp (Amgen). EPO is being much misused as a performance-enhancing drug in endurance athletes. Belongs to the EPO/TPO family. Erythropoietin entry Journey into a tiny world - Issue 84 of July 2007