potassium voltage-gated channel subfamily H member 2
Last updated 18 Aug 2020
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The KCNH2 gene belongs to a large family of genes that provide instructions for making potassium channels. These channels, which transport positively charged atoms (ions) of potassium out of cells, play key roles in a cell's ability to generate and transmit electrical signals.
Normal function
The KCNH2 gene belongs to a large family of genes that provide instructions for making potassium channels. These channels, which transport positively charged atoms (ions) of potassium out of cells, play key roles in a cell's ability to generate and transmit electrical signals.
The specific function of a potassium channel depends on its protein components and its location in the body. Channels made with KCNH2 proteins (also known as hERG1) are active in heart (cardiac) muscle. They are involved in recharging the cardiac muscle after each heartbeat to maintain a regular rhythm. The KCNH2 protein is also produced in nerve cells and certain immune cells (microglia) in the brain and spinal cord (central nervous system).
The proteins produced from the KCNH2 gene and another gene, KCNE2, interact to form a functional potassium channel. Four alpha subunits, each produced from the KCNH2 gene, form the structure of each channel. One beta subunit, produced from the KCNE2 gene, attaches (binds) to the channel and regulates its activity.
Conditions referring to this gene or chromosome
Other names
ERG1
ether-a-go-go related gene potassium channel 1
H-ERG
HERG
HERG1
human ether a-go-go-related gene
KCNH2_HUMAN
Kv11.1
LQT2
potassium channel, voltage gated eag related subfamily H, member 2
potassium voltage-gated channel, subfamily H (eag-related), member 2
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Further reading and references
- potassium voltage-gated channel subfamily H member 2; MedlinePlus, National Library of Medicine.
- Brugada R, Hong K, Dumaine R, Cordeiro J, Gaita F, Borggrefe M, Menendez TM, Brugada J, Pollevick GD, Wolpert C, Burashnikov E, Matsuo K, Wu YS, Guerchicoff A, Bianchi F, Giustetto C, Schimpf R, Brugada P, Antzelevitch C. Sudden death associated with short-QT syndrome linked to mutations in HERG. Circulation. 2004 Jan 6;109(1):30-5. doi: 10.1161/01.CIR.0000109482.92774.3A. Epub 2003 Dec 15.
- Cordeiro JM, Brugada R, Wu YS, Hong K, Dumaine R. Modulation of I(Kr) inactivation by mutation N588K in KCNH2: a link to arrhythmogenesis in short QT syndrome. Cardiovasc Res. 2005 Aug 15;67(3):498-509. doi: 10.1016/j.cardiores.2005.02.018. Epub 2005 Mar 28.
- Groffen AJ, Bikker H, Christiaans I. Long QT Syndrome Overview. 2003 Feb 20 [updated 2024 Mar 21]. In: Adam MP, Bick S, Mirzaa GM, Wallace SE, Amemiya A, editors. GeneReviews(R) [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2026. Available from http://www.ncbi.nlm.nih.gov/books/NBK1129/
- Hong K, Bjerregaard P, Gussak I, Brugada R. Short QT syndrome and atrial fibrillation caused by mutation in KCNH2. J Cardiovasc Electrophysiol. 2005 Apr;16(4):394-6. doi: 10.1046/j.1540-8167.2005.40621.x.
- McBride CM, Smith AM, Smith JL, Reloj AR, Velasco EJ, Powell J, Elayi CS, Bartos DC, Burgess DE, Delisle BP. Mechanistic basis for type 2 long QT syndrome caused by KCNH2 mutations that disrupt conserved arginine residues in the voltage sensor. J Membr Biol. 2013 May;246(5):355-64. doi: 10.1007/s00232-013-9539-6. Epub 2013 Apr 2.
- Paulussen AD, Gilissen RA, Armstrong M, Doevendans PA, Verhasselt P, Smeets HJ, Schulze-Bahr E, Haverkamp W, Breithardt G, Cohen N, Aerssens J. Genetic variations of KCNQ1, KCNH2, SCN5A, KCNE1, and KCNE2 in drug-induced long QT syndrome patients. J Mol Med (Berl). 2004 Mar;82(3):182-8. doi: 10.1007/s00109-003-0522-z. Epub 2004 Feb 4.
- Paulussen AD, Raes A, Jongbloed RJ, Gilissen RA, Wilde AA, Snyders DJ, Smeets HJ, Aerssens J. HERG mutation predicts short QT based on channel kinetics but causes long QT by heterotetrameric trafficking deficiency. Cardiovasc Res. 2005 Aug 15;67(3):467-75. doi: 10.1016/j.cardiores.2005.05.017.
- Sanguinetti MC. HERG1 channelopathies. Pflugers Arch. 2010 Jul;460(2):265-76. doi: 10.1007/s00424-009-0758-8. Epub 2009 Nov 22.
- Schimpf R, Wolpert C, Gaita F, Giustetto C, Borggrefe M. Short QT syndrome. Cardiovasc Res. 2005 Aug 15;67(3):357-66. doi: 10.1016/j.cardiores.2005.03.026.
- Smith JL, Anderson CL, Burgess DE, Elayi CS, January CT, Delisle BP. Molecular pathogenesis of long QT syndrome type 2. J Arrhythm. 2016 Oct;32(5):373-380. doi: 10.1016/j.joa.2015.11.009. Epub 2016 Jan 22.
- Sun Y, Quan XQ, Fromme S, Cox RH, Zhang P, Zhang L, Guo D, Guo J, Patel C, Kowey PR, Yan GX. A novel mutation in the KCNH2 gene associated with short QT syndrome. J Mol Cell Cardiol. 2011 Mar;50(3):433-41. doi: 10.1016/j.yjmcc.2010.11.017. Epub 2010 Dec 3.
- Thomas D, Kiehn J, Katus HA, Karle CA. Defective protein trafficking in hERG-associated hereditary long QT syndrome (LQT2): molecular mechanisms and restoration of intracellular protein processing. Cardiovasc Res. 2003 Nov 1;60(2):235-41. doi: 10.1016/j.cardiores.2003.08.002.
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