Reviewed March 2013
What is the official name of the SCNN1B gene?
The official name of this gene is “sodium channel, non-voltage-gated 1, beta subunit.”
SCNN1B is the gene's official symbol. The SCNN1B gene is also known by other names, listed below.
What is the normal function of the SCNN1B gene?
The SCNN1B gene provides instructions for making one piece, the beta subunit, of a protein complex called the epithelial sodium channel (ENaC). The channel is composed of alpha, beta, and gamma subunits, each of which is produced from a different gene. These channels are found at the surface of certain cells called epithelial cells in many tissues of the body, including the kidneys, lungs, colon, and sweat glands. The ENaC channel transports sodium into cells.
In the kidney, ENaC channels open in response to signals that sodium levels in the blood are too low, which allows sodium to flow into cells. From the kidney cells, this sodium is returned to the bloodstream (a process called reabsorption) rather than being removed from the body in urine. In addition to regulating the amount of sodium in the body, the flow of sodium ions helps control the movement of water in tissues. For example, ENaC channels in lung cells help regulate the amount of fluid in the lungs.
Does the SCNN1B gene share characteristics with other genes?
The SCNN1B gene belongs to a family of genes called SC (sodium channels).
A gene family is a group of genes that share important characteristics. Classifying individual genes into families helps researchers describe how genes are related to each other. For more information, see What are gene families? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genefamilies) in the Handbook.
How are changes in the SCNN1B gene related to health conditions?
- Liddle syndrome - caused by mutations in the SCNN1B gene
At least 16 mutations in the SCNN1B gene can cause a condition known as Liddle syndrome. People with Liddle syndrome have high blood pressure (hypertension) and low levels of potassium in their blood (hypokalemia), often beginning in childhood. Mutations in the SCNN1B gene associated with Liddle syndrome lead to the production of an abnormally short beta subunit protein or result in the replacement of a single protein building block (amino acid) in the protein. These changes affect an important region of the protein involved in signaling for its breakdown (degradation). As a result of the mutations, the protein is not degraded, and more ENaC channels remain at the cell surface. The increase in channels at the cell surface abnormally increases the reabsorption of sodium (followed by water), which leads to hypertension. Reabsorption of sodium into the blood is linked with removal of potassium from the blood, so excess sodium reabsorption leads to hypokalemia.
- pseudohypoaldosteronism type 1 - caused by mutations in the SCNN1B gene
Mutations in the SCNN1B gene have been identified in people with pseudohypoaldosteronism type 1 (PHA1). This condition typically begins in infancy and is characterized by low levels of sodium (hyponatremia) and high levels of potassium (hyperkalemia) in the blood, and severe dehydration due to the loss of excess sodium and fluid in urine. In particular, SCNN1B gene mutations are involved in autosomal recessive PHA1, a severe form of the condition that does not improve with age.
Mutations in the SCNN1B gene that cause PHA1 often result in the replacement of a single amino acid in the beta subunit protein or lead to an abnormally short protein. These mutations result in reduced or absent ENaC channel activity. As a result, sodium reabsorption is impaired, leading to hyponatremia and other signs and symptoms of autosomal recessive PHA1. The reduced function of ENaC channels in lung epithelial cells leads to excess fluid in the lungs and recurrent lung infections.
- other disorders - associated with the SCNN1B gene
Some people with cystic fibrosis-like syndrome have a mutation or a normal gene variation (polymorphism) in the SCNN1B gene. People with cystic fibrosis-like syndrome (also known as atypical cystic fibrosis or bronchiectasis with or without elevated sweat chloride type 1) have signs and symptoms that resemble those of cystic fibrosis, including breathing problems and lung infections. However, changes in the gene most commonly associated with cystic fibrosis, CFTR, cannot explain development of the condition. It is thought that a mutation or gene variation in the SCNN1B gene can disrupt sodium transport and fluid balance, which leads to the signs and symptoms of cystic fibrosis-like syndrome.
Where is the SCNN1B gene located?
Cytogenetic Location: 16p12.2-p12.1
Molecular Location on chromosome 16: base pairs 23,302,269 to 23,381,298
The SCNN1B gene is located on the short (p) arm of chromosome 16 between positions 12.2 and 12.1.
More precisely, the SCNN1B gene is located from base pair 23,302,269 to base pair 23,381,298 on chromosome 16.
See How do geneticists indicate the location of a gene? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genelocation) in the Handbook.
Where can I find additional information about SCNN1B?
You and your healthcare professional may find the following resources about SCNN1B helpful.
Genetic Testing Registry - Repository of genetic test information
- GTR: Genetic tests for SCNN1B (http://www.ncbi.nlm.nih.gov/gtr/tests/?term=6338%5Bgeneid%5D)
You may also be interested in these resources, which are designed for genetics professionals and researchers.
OMIM - Genetic disorder catalog
- BRONCHIECTASIS WITH OR WITHOUT ELEVATED SWEAT CHLORIDE 1 (http://omim.org/entry/211400)
- SODIUM CHANNEL, NONVOLTAGE-GATED 1, BETA SUBUNIT (http://omim.org/entry/600760)
Research Resources - Tools for researchers
- Atlas of Genetics and Cytogenetics in Oncology and Haematology (http://atlasgeneticsoncology.org/Genes/GC_SCNN1B.html)
- GeneCards (http://www.genecards.org/cgi-bin/carddisp.pl?id_type=entrezgene&id=6338)
- HGNC Gene Family: Ion channels / Sodium channel, nonvoltage-gated (http://www.genenames.org/genefamilies/SCNN)
- HGNC Gene Symbol Report (http://www.genenames.org/data/hgnc_data.php?hgnc_id=10600)
- NCBI Gene (http://www.ncbi.nlm.nih.gov/gene/6338)
What other names do people use for the SCNN1B gene or gene products?
- amiloride-sensitive sodium channel subunit beta
- epithelial Na(+) channel subunit beta
- nasal epithelial sodium channel beta subunit
- sodium channel, nonvoltage-gated 1, beta
See How are genetic conditions and genes named? (http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/naming) in the Handbook.
What glossary definitions help with understanding SCNN1B?
amino acid ;
autosomal recessive ;
sodium channel ;
You may find definitions for these and many other terms in the Genetics Home Reference
- Abriel H, Loffing J, Rebhun JF, Pratt JH, Schild L, Horisberger JD, Rotin D, Staub O. Defective regulation of the epithelial Na+ channel by Nedd4 in Liddle's syndrome. J Clin Invest. 1999 Mar;103(5):667-73. (http://www.ncbi.nlm.nih.gov/pubmed/10074483?dopt=Abstract)
- Azad AK, Rauh R, Vermeulen F, Jaspers M, Korbmacher J, Boissier B, Bassinet L, Fichou Y, des Georges M, Stanke F, De Boeck K, Dupont L, Balascáková M, Hjelte L, Lebecque P, Radojkovic D, Castellani C, Schwartz M, Stuhrmann M, Schwarz M, Skalicka V, de Monestrol I, Girodon E, Férec C, Claustres M, Tümmler B, Cassiman JJ, Korbmacher C, Cuppens H. Mutations in the amiloride-sensitive epithelial sodium channel in patients with cystic fibrosis-like disease. Hum Mutat. 2009 Jul;30(7):1093-103. doi: 10.1002/humu.21011. (http://www.ncbi.nlm.nih.gov/pubmed/19462466?dopt=Abstract)
- Bogdanović R, Kuburović V, Stajić N, Mughal SS, Hilger A, Ninić S, Prijić S, Ludwig M. Liddle syndrome in a Serbian family and literature review of underlying mutations. Eur J Pediatr. 2012 Mar;171(3):471-8. doi: 10.1007/s00431-011-1581-8. Epub 2011 Sep 29. Review. (http://www.ncbi.nlm.nih.gov/pubmed/21956615?dopt=Abstract)
- Canessa CM, Schild L, Buell G, Thorens B, Gautschi I, Horisberger JD, Rossier BC. Amiloride-sensitive epithelial Na+ channel is made of three homologous subunits. Nature. 1994 Feb 3;367(6462):463-7. (http://www.ncbi.nlm.nih.gov/pubmed/8107805?dopt=Abstract)
- Chang SS, Grunder S, Hanukoglu A, Rösler A, Mathew PM, Hanukoglu I, Schild L, Lu Y, Shimkets RA, Nelson-Williams C, Rossier BC, Lifton RP. Mutations in subunits of the epithelial sodium channel cause salt wasting with hyperkalaemic acidosis, pseudohypoaldosteronism type 1. Nat Genet. 1996 Mar;12(3):248-53. (http://www.ncbi.nlm.nih.gov/pubmed/8589714?dopt=Abstract)
- Chen SY, Bhargava A, Mastroberardino L, Meijer OC, Wang J, Buse P, Firestone GL, Verrey F, Pearce D. Epithelial sodium channel regulated by aldosterone-induced protein sgk. Proc Natl Acad Sci U S A. 1999 Mar 2;96(5):2514-9. (http://www.ncbi.nlm.nih.gov/pubmed/10051674?dopt=Abstract)
- Hansson JH, Schild L, Lu Y, Wilson TA, Gautschi I, Shimkets R, Nelson-Williams C, Rossier BC, Lifton RP. A de novo missense mutation of the beta subunit of the epithelial sodium channel causes hypertension and Liddle syndrome, identifying a proline-rich segment critical for regulation of channel activity. Proc Natl Acad Sci U S A. 1995 Dec 5;92(25):11495-9. (http://www.ncbi.nlm.nih.gov/pubmed/8524790?dopt=Abstract)
- Masilamani S, Kim GH, Mitchell C, Wade JB, Knepper MA. Aldosterone-mediated regulation of ENaC alpha, beta, and gamma subunit proteins in rat kidney. J Clin Invest. 1999 Oct;104(7):R19-23. (http://www.ncbi.nlm.nih.gov/pubmed/10510339?dopt=Abstract)
- Mutesa L, Azad AK, Verhaeghe C, Segers K, Vanbellinghen JF, Ngendahayo L, Rusingiza EK, Mutwa PR, Rulisa S, Koulischer L, Cassiman JJ, Cuppens H, Bours V. Genetic analysis of Rwandan patients with cystic fibrosis-like symptoms: identification of novel cystic fibrosis transmembrane conductance regulator and epithelial sodium channel gene variants. Chest. 2009 May;135(5):1233-42. doi: 10.1378/chest.08-2246. Epub 2008 Nov 18. (http://www.ncbi.nlm.nih.gov/pubmed/19017867?dopt=Abstract)
- NCBI Gene (http://www.ncbi.nlm.nih.gov/gene/6338)
- Sheridan MB, Fong P, Groman JD, Conrad C, Flume P, Diaz R, Harris C, Knowles M, Cutting GR. Mutations in the beta-subunit of the epithelial Na+ channel in patients with a cystic fibrosis-like syndrome. Hum Mol Genet. 2005 Nov 15;14(22):3493-8. Epub 2005 Oct 5. (http://www.ncbi.nlm.nih.gov/pubmed/16207733?dopt=Abstract)
- Shimkets RA, Warnock DG, Bositis CM, Nelson-Williams C, Hansson JH, Schambelan M, Gill JR Jr, Ulick S, Milora RV, Findling JW, et al. Liddle's syndrome: heritable human hypertension caused by mutations in the beta subunit of the epithelial sodium channel. Cell. 1994 Nov 4;79(3):407-14. (http://www.ncbi.nlm.nih.gov/pubmed/7954808?dopt=Abstract)
- Snyder PM, Price MP, McDonald FJ, Adams CM, Volk KA, Zeiher BG, Stokes JB, Welsh MJ. Mechanism by which Liddle's syndrome mutations increase activity of a human epithelial Na+ channel. Cell. 1995 Dec 15;83(6):969-78. (http://www.ncbi.nlm.nih.gov/pubmed/8521520?dopt=Abstract)
- OMIM: SODIUM CHANNEL, NONVOLTAGE-GATED 1, BETA SUBUNIT (http://omim.org/entry/600760)
- Staub O, Gautschi I, Ishikawa T, Breitschopf K, Ciechanover A, Schild L, Rotin D. Regulation of stability and function of the epithelial Na+ channel (ENaC) by ubiquitination. EMBO J. 1997 Nov 3;16(21):6325-36. (http://www.ncbi.nlm.nih.gov/pubmed/9351815?dopt=Abstract)
- Warnock DG. Liddle syndrome: genetics and mechanisms of Na+ channel defects. Am J Med Sci. 2001 Dec;322(6):302-7. Review. (http://www.ncbi.nlm.nih.gov/pubmed/11780687?dopt=Abstract)
The resources on this site should not be used as a substitute for
professional medical care or advice. Users seeking information about
a personal genetic disease, syndrome, or condition should consult with a qualified
See How can I find a genetics professional in my area? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.