Skip navigation

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

URL of this page:

BMPR1A gene

bone morphogenetic protein receptor type 1A

Normal Function

The BMPR1A gene provides instructions for making a protein called bone morphogenetic protein receptor 1A. This receptor protein has a specific site into which certain other proteins, called ligands, fit like keys into locks. Specifically, the BMPR1A protein attaches (binds) to ligands in the transforming growth factor beta (TGF-β) pathway. This signaling pathway allows the environment outside the cell to affect how the cell produces other proteins. The BMPR1A receptor protein and its ligands are involved in transmitting chemical signals from the cell membrane to the nucleus.

When the BMPR1A protein is bound to a ligand, it turns on (activates) a group of related proteins (a protein complex) called SMAD proteins. The activated SMAD protein complex is then transported into the cell's nucleus, where it regulates cell growth and division (proliferation) and the activity of particular genes.

Health Conditions Related to Genetic Changes

Juvenile polyposis syndrome

More than 60 mutations in the BMPR1A gene have been found to cause juvenile polyposis syndrome. Most BMPR1A gene mutations result in the production of an abnormally short, nonfunctional protein. As a result, the BMPR1A protein cannot bind to ligands in the TGF-β pathway. This disruption in binding interferes with the activation of the SMAD protein complex. This inactive complex is not transported to the nucleus, where it is needed to regulate cell growth and the activity of certain genes. Unregulated cell growth can lead to polyp formation in people with juvenile polyposis syndrome.

More About This Health Condition

Other Names for This Gene

  • activin A receptor, type II-like kinase 3
  • ALK3
  • bone morphogenetic protein receptor type IA
  • bone morphogenetic protein receptor, type IA
  • bone morphogenetic protein receptor, type IA precursor
  • CD292
  • serine/threonine-protein kinase receptor R5
  • SKR5

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


  • Aretz S, Stienen D, Uhlhaas S, Stolte M, Entius MM, Loff S, Back W, Kaufmann A, Keller KM, Blaas SH, Siebert R, Vogt S, Spranger S, Holinski-Feder E, Sunde L, Propping P, Friedl W. High proportion of large genomic deletions and a genotype phenotype update in 80 unrelated families with juvenile polyposis syndrome. J Med Genet. 2007 Nov;44(11):702-9. doi: 10.1136/jmg.2007.052506. Epub 2007 Sep 14. Citation on PubMed or Free article on PubMed Central
  • Calva-Cerqueira D, Chinnathambi S, Pechman B, Bair J, Larsen-Haidle J, Howe JR. The rate of germline mutations and large deletions of SMAD4 and BMPR1A in juvenile polyposis. Clin Genet. 2009 Jan;75(1):79-85. doi: 10.1111/j.1399-0004.2008.01091.x. Epub 2008 Sep 24. Citation on PubMed
  • Howe JR, Bair JL, Sayed MG, Anderson ME, Mitros FA, Petersen GM, Velculescu VE, Traverso G, Vogelstein B. Germline mutations of the gene encoding bone morphogenetic protein receptor 1A in juvenile polyposis. Nat Genet. 2001 Jun;28(2):184-7. doi: 10.1038/88919. Citation on PubMed
  • Howe JR, Sayed MG, Ahmed AF, Ringold J, Larsen-Haidle J, Merg A, Mitros FA, Vaccaro CA, Petersen GM, Giardiello FM, Tinley ST, Aaltonen LA, Lynch HT. The prevalence of MADH4 and BMPR1A mutations in juvenile polyposis and absence of BMPR2, BMPR1B, and ACVR1 mutations. J Med Genet. 2004 Jul;41(7):484-91. doi: 10.1136/jmg.2004.018598. Citation on PubMed or Free article on PubMed Central
  • Pyatt RE, Pilarski R, Prior TW. Mutation screening in juvenile polyposis syndrome. J Mol Diagn. 2006 Feb;8(1):84-8. doi: 10.2353/jmoldx.2006.050072. 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.