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ACVRL1 gene

activin A receptor like type 1

Normal Function

The ACVRL1 gene provides instructions for making a protein called activin receptor-like kinase 1. This protein is found on the surface of cells, especially in the lining of developing arteries.

The ACVRL1 protein is a receptor. It acts as a "lock" waiting for a specific protein, called its ligand, to serve as the "key." In the case of the ACVRL1 protein, the ligand is called transforming growth factor beta. The interaction between these proteins plays a role in the development of blood vessels. In particular, this protein interaction is involved in the specialization of new blood vessels into arteries or veins.

Health Conditions Related to Genetic Changes

Hereditary hemorrhagic telangiectasia

Dozens of mutations in the ACVRL1 gene have been found to cause hereditary hemorrhagic telangiectasia type 2. Many ACVRL1 gene mutations substitute one protein building block (amino acid) for another amino acid in the ACVRL1 protein, which impairs the protein's function. Other mutations prevent production of the ACVRL1 protein or result in an abnormally small protein that cannot function. The shortage of functional ACVRL1 protein appears to interfere with the development of boundaries between arteries and veins, resulting in the signs and symptoms of hereditary hemorrhagic telangiectasia type 2.

More About This Health Condition

Pulmonary arterial hypertension

MedlinePlus Genetics provides information about Pulmonary arterial hypertension

More About This Health Condition

Other disorders

A common genetic variation (polymorphism) in the ACVRL1 gene has been found to appear more often in people who develop arteriovenous malformations in the brain, but who do not have other signs or symptoms of hereditary hemorrhagic telangiectasia, than in the general population. The polymorphism replaces a particular DNA building block (nucleotide) called adenine with the nucleotide guanine (written as IVS3-35 A>G). This genetic variation may affect the development of blood vessels in the brain, resulting in an increased risk of arteriovenous malformations.

Other Names for This Gene

  • activin A receptor type II-like 1
  • activin A receptor type IL
  • Activin A receptor, type II-like kinase 1
  • ALK-1
  • ALK1
  • EC
  • HHT
  • HHT2
  • ORW2
  • Serine/threonine-protein kinase Receptor R3 Precursor
  • SKR3
  • TGF-B Superfamily Receptor Type I

Additional Information & Resources

Tests Listed in the Genetic Testing Registry

Scientific Articles on PubMed

Gene and Variant Databases


  • Azuma H. Genetic and molecular pathogenesis of hereditary hemorrhagic telangiectasia. J Med Invest. 2000 Aug;47(3-4):81-90. Citation on PubMed
  • Lebrin F, Deckers M, Bertolino P, Ten Dijke P. TGF-beta receptor function in the endothelium. Cardiovasc Res. 2005 Feb 15;65(3):599-608. doi: 10.1016/j.cardiores.2004.10.036. Citation on PubMed
  • Lesca G, Plauchu H, Coulet F, Lefebvre S, Plessis G, Odent S, Riviere S, Leheup B, Goizet C, Carette MF, Cordier JF, Pinson S, Soubrier F, Calender A, Giraud S; French Rendu-Osler Network. Molecular screening of ALK1/ACVRL1 and ENG genes in hereditary hemorrhagic telangiectasia in France. Hum Mutat. 2004 Apr;23(4):289-99. doi: 10.1002/humu.20017. Citation on PubMed
  • Letteboer TG, Zewald RA, Kamping EJ, de Haas G, Mager JJ, Snijder RJ, Lindhout D, Hennekam FA, Westermann CJ, Ploos van Amstel JK. Hereditary hemorrhagic telangiectasia: ENG and ALK-1 mutations in Dutch patients. Hum Genet. 2005 Jan;116(1-2):8-16. doi: 10.1007/s00439-004-1196-5. Epub 2004 Oct 23. Citation on PubMed
  • Pawlikowska L, Tran MN, Achrol AS, Ha C, Burchard E, Choudhry S, Zaroff J, Lawton MT, Castro R, McCulloch CE, Marchuk D, Kwok PY, Young WL; UCSF BAVM Study Project. Polymorphisms in transforming growth factor-beta-related genes ALK1 and ENG are associated with sporadic brain arteriovenous malformations. Stroke. 2005 Oct;36(10):2278-80. doi: 10.1161/01.STR.0000182253.91167.fa. Epub 2005 Sep 22. Citation on PubMed
  • van den Driesche S, Mummery CL, Westermann CJ. Hereditary hemorrhagic telangiectasia: an update on transforming growth factor beta signaling in vasculogenesis and angiogenesis. Cardiovasc Res. 2003 Apr 1;58(1):20-31. doi: 10.1016/s0008-6363(02)00852-0. Citation on PubMed

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.