Reviewed November 2011
What is the official name of the CHRNG gene?
The official name of this gene is “cholinergic receptor, nicotinic, gamma (muscle).”
CHRNG is the gene's official symbol. The CHRNG gene is also known by other names, listed below.
What is the normal function of the CHRNG gene?
The CHRNG gene provides instructions for making the gamma (γ) protein component (subunit) of the acetylcholine receptor (AChR) protein. The AChR protein is found in the membrane of skeletal muscle cells and is critical for signaling between nerve and muscle cells. Signaling between these cells is necessary for movement. The AChR protein consists of five subunits, each of which is produced from a different gene. The subunits are assembled into the AChR protein in the endoplasmic reticulum, a cell structure involved in protein processing and transport, before being transported to the cell membrane. The γ subunit is found only in the fetal AChR protein. At about the thirty-third week of pregnancy, the γ subunit is replaced by the epsilon (ε) subunit, which is produced by the CHRNE gene, to form the adult AChR protein.
How are changes in the CHRNG gene related to health conditions?
- multiple pterygium syndrome - caused by mutations in the CHRNG gene
At least 14 mutations in the CHRNG gene have been found to cause multiple pterygium syndrome, a condition characterized by webbing of the skin (pterygium) and a lack of muscle movement (akinesia) before birth. These mutations include replacing, adding, or deleting DNA building blocks (nucleotides). CHRNG gene mutations result in an impaired or missing γ subunit. The severity of the CHRNG gene mutation influences the severity of the condition. Typically, mutations that prevent the production of any γ subunit will result in lethal multiple pterygium syndrome, which is fatal before birth, while mutations that allow the production of some γ subunit will lead to the milder form of this condition called multiple pterygium syndrome, Escobar type. A shortage of a functional γ subunit prevents the fetal AChR protein from being assembled or properly placed in the muscle cell membrane. As a result, the fetal AChR protein cannot function and the communication between nerve and muscle cells in the developing fetus is impaired. A lack of signaling between nerve and muscle cells leads to akinesia and pterygium before birth, and many of the other signs and symptoms of multiple pterygium syndrome.
Where is the CHRNG gene located?
Cytogenetic Location: 2q37.1
Molecular Location on chromosome 2: base pairs 232,539,726 to 232,546,327
The CHRNG gene is located on the long (q) arm of chromosome 2 at position 37.1.
More precisely, the CHRNG gene is located from base pair 232,539,726 to base pair 232,546,327 on chromosome 2.
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 CHRNG?
You and your healthcare professional may find the following resources about CHRNG helpful.
Educational resources - Information pages
- Molecular Biology of the Cell (fourth edition, 2002): The Acetylcholine Receptors at the Neuromuscular Junction Are Transmitter-gated Cation Channels (http://www.ncbi.nlm.nih.gov/books/NBK26910/)
- Molecular Cell Biology (fourth edition, 2000): All Five Subunits in the Nicotinic Acetylcholine Receptor Contribute to the Ion Channel (http://www.ncbi.nlm.nih.gov/books/NBK21586/)
- Molecular Cell Biology (fourth edition, 2000): Signals From the Motor Neuron Regulate the Expression and Localization of the Acetylcholine Receptor (AChR) (figure) (http://www.ncbi.nlm.nih.gov/books/NBK21742/figure/A6882/)
Genetic Testing Registry - Repository of genetic test information
- GTR: Genetic tests for CHRNG (http://www.ncbi.nlm.nih.gov/gtr/tests/?term=1146%5Bgeneid%5D)
You may also be interested in these resources, which are designed for genetics professionals and researchers.
- PubMed - Recent literature (http://www.ncbi.nlm.nih.gov/pubmed?term=%28CHRNG%5BTIAB%5D%29%20AND%20%28%28Genes%5BMH%5D%29%20OR%20%28Genetic%20Phenomena%5BMH%5D%29%29%20AND%20english%5Bla%5D%20AND%20human%5Bmh%5D%20AND%20%22last%203600%20days%22%5Bdp%5D)
- OMIM - Genetic disorder catalog (http://omim.org/entry/100730)
Research Resources - Tools for researchers
- Atlas of Genetics and Cytogenetics in Oncology and Haematology (http://atlasgeneticsoncology.org/Genes/GC_CHRNG.html)
- HGNC Gene Family: Cholinergic receptors (http://www.genenames.org/genefamilies/CHR)
- HGNC Gene Family: Ligand-gated ion channels / Acetylcholine receptors, nicotinic (http://www.genenames.org/genefamilies/LGIC)
- HGNC Gene Symbol Report (http://www.genenames.org/cgi-bin/gene_symbol_report?q=data/hgnc_data.php&hgnc_id=1967)
- NCBI Gene (http://www.ncbi.nlm.nih.gov/gene/1146)
What other names do people use for the CHRNG gene or gene products?
- acetylcholine gamma muscle receptor subunit
- acetylcholine receptor, muscle, gamma subunit
- acetylcholine receptor subunit gamma
- cholinergic gamma nicotinic receptor
- cholinergic receptor, nicotinic, gamma
- cholinergic receptor, nicotinic, gamma polypeptide
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 CHRNG?
cell membrane ;
endoplasmic reticulum ;
muscle cell ;
muscle cells ;
skeletal muscle ;
You may find definitions for these and many other terms in the Genetics Home Reference
- OMIM: CHOLINERGIC RECEPTOR, NICOTINIC, GAMMA POLYPEPTIDE (http://omim.org/entry/100730)
- Hoffmann K, Muller JS, Stricker S, Megarbane A, Rajab A, Lindner TH, Cohen M, Chouery E, Adaimy L, Ghanem I, Delague V, Boltshauser E, Talim B, Horvath R, Robinson PN, Lochmüller H, Hübner C, Mundlos S. Escobar syndrome is a prenatal myasthenia caused by disruption of the acetylcholine receptor fetal gamma subunit. Am J Hum Genet. 2006 Aug;79(2):303-12. Epub 2006 Jun 20. (http://www.ncbi.nlm.nih.gov/pubmed/16826520?dopt=Abstract)
- Michalk A, Stricker S, Becker J, Rupps R, Pantzar T, Miertus J, Botta G, Naretto VG, Janetzki C, Yaqoob N, Ott CE, Seelow D, Wieczorek D, Fiebig B, Wirth B, Hoopmann M, Walther M, Körber F, Blankenburg M, Mundlos S, Heller R, Hoffmann K. Acetylcholine receptor pathway mutations explain various fetal akinesia deformation sequence disorders. Am J Hum Genet. 2008 Feb;82(2):464-76. doi: 10.1016/j.ajhg.2007.11.006. (http://www.ncbi.nlm.nih.gov/pubmed/18252226?dopt=Abstract)
- Morgan NV, Brueton LA, Cox P, Greally MT, Tolmie J, Pasha S, Aligianis IA, van Bokhoven H, Marton T, Al-Gazali L, Morton JE, Oley C, Johnson CA, Trembath RC, Brunner HG, Maher ER. Mutations in the embryonal subunit of the acetylcholine receptor (CHRNG) cause lethal and Escobar variants of multiple pterygium syndrome. Am J Hum Genet. 2006 Aug;79(2):390-5. Epub 2006 Jun 20. (http://www.ncbi.nlm.nih.gov/pubmed/16826531?dopt=Abstract)
- NCBI Gene (http://www.ncbi.nlm.nih.gov/gene/1146)
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.