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EPOR gene

erythropoietin receptor

Normal Function

The EPOR gene provides instructions for making a protein called the erythropoietin receptor. Erythropoietin is a hormone that directs the production of new red blood cells (erythrocytes) in the bone marrow. Red blood cells make up about half of total blood volume, and their primary function is to carry oxygen from the lungs to tissues and organs throughout the body. New red blood cells are constantly being produced by the body as worn-out red blood cells are broken down. To trigger the production of red blood cells, erythropoietin attaches (binds) to the erythropoietin receptor. This binding turns on (activates) the receptor, which stimulates several signaling pathways (particularly a cascade of signals known as the JAK/STAT pathway) that lead to the formation and maturation of red blood cells.

Health Conditions Related to Genetic Changes

Familial erythrocytosis

At least 16 mutations in the EPOR gene have been found to cause familial erythrocytosis, an inherited condition characterized by an increased number of red blood cells and an elevated risk of abnormal blood clots. When familial erythrocytosis results from EPOR gene mutations, it is often designated ECYT1.

Most of the identified mutations in the EPOR gene lead to the production of an abnormally short version of the erythropoietin receptor. A few mutations change single protein building blocks (amino acids) in the receptor. All of these mutations alter the structure of the receptor, causing it to remain activated for an abnormally long time after binding to erythropoietin. The overactive receptor signals the production of red blood cells even when no more are needed, which leads to an excess of these cells in the bloodstream.

More About This Health Condition

Other Names for This Gene

  • EPO-R

Additional Information & Resources

Tests Listed in the Genetic Testing Registry

Scientific Articles on PubMed

Catalog of Genes and Diseases from OMIM

Gene and Variant Databases


  • Al-Sheikh M, Mazurier E, Gardie B, Casadevall N, Galacteros F, Goossens M, Wajcman H, Prehu C, Ugo V. A study of 36 unrelated cases with pure erythrocytosis revealed three new mutations in the erythropoietin receptor gene. Haematologica. 2008 Jul;93(7):1072-5. doi: 10.3324/haematol.12260. Epub 2008 May 19. Citation on PubMed
  • Constantinescu SN, Ghaffari S, Lodish HF. The Erythropoietin Receptor: Structure, Activation and Intracellular Signal Transduction. Trends Endocrinol Metab. 1999 Dec;10(1):18-23. doi: 10.1016/s1043-2760(98)00101-5. Citation on PubMed
  • de la Chapelle A, Traskelin AL, Juvonen E. Truncated erythropoietin receptor causes dominantly inherited benign human erythrocytosis. Proc Natl Acad Sci U S A. 1993 May 15;90(10):4495-9. doi: 10.1073/pnas.90.10.4495. Citation on PubMed or Free article on PubMed Central
  • Hodges VM, Rainey S, Lappin TR, Maxwell AP. Pathophysiology of anemia and erythrocytosis. Crit Rev Oncol Hematol. 2007 Nov;64(2):139-58. doi: 10.1016/j.critrevonc.2007.06.006. Epub 2007 Jul 25. Citation on PubMed
  • Huang LJ, Shen YM, Bulut GB. Advances in understanding the pathogenesis of primary familial and congenital polycythaemia. Br J Haematol. 2010 Mar;148(6):844-52. doi: 10.1111/j.1365-2141.2009.08069.x. Epub 2010 Jan 20. Citation on PubMed or Free article on PubMed Central
  • Percy MJ, Rumi E. Genetic origins and clinical phenotype of familial and acquired erythrocytosis and thrombocytosis. Am J Hematol. 2009 Jan;84(1):46-54. doi: 10.1002/ajh.21313. Citation on PubMed
  • Percy MJ. Genetically heterogeneous origins of idiopathic erythrocytosis. Hematology. 2007 Apr;12(2):131-9. doi: 10.1080/10245330601111979. Citation on PubMed
  • Watowich SS, Xie X, Klingmuller U, Kere J, Lindlof M, Berglund S, de la Chapelle A. Erythropoietin receptor mutations associated with familial erythrocytosis cause hypersensitivity to erythropoietin in the heterozygous state. Blood. 1999 Oct 1;94(7):2530-2. Citation on PubMed
  • Watowich SS. The erythropoietin receptor: molecular structure and hematopoietic signaling pathways. J Investig Med. 2011 Oct;59(7):1067-72. doi: 10.2310/JIM.0b013e31820fb28c. Citation on PubMed or Free article on PubMed Central

The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.