Reviewed February 2011
What is the official name of the ACTA2 gene?
The official name of this gene is “actin, alpha 2, smooth muscle, aorta.”
ACTA2 is the gene's official symbol. The ACTA2 gene is also known by other names, listed below.
What is the normal function of the ACTA2 gene?
The ACTA2 gene provides instructions for making a protein called smooth muscle alpha (α)-2 actin, which is part of the actin protein family. Actin proteins are important for cell movement and the tensing of muscle fibers (muscle contraction). These proteins also help maintain the cytoskeleton, which is the structural framework that determines cell shape and organizes cell contents.
Smooth muscle α-2 actin is found in vascular smooth muscle cells. Layers of these cells are found in the walls of the arteries, which are blood vessels that carry blood from the heart to the rest of the body. Within vascular smooth muscle cells, smooth muscle α-2 actin forms the core of structures called sarcomeres, which are necessary for muscles to contract. This ability to contract allows the arteries to maintain their shape instead of stretching out as blood is pumped through them.
How are changes in the ACTA2 gene related to health conditions?
- familial thoracic aortic aneurysm and dissection - increased risk from variations of the ACTA2 gene
At least nine ACTA2 gene mutations have been identified in people with familial thoracic aortic aneurysm and dissection (familial TAAD). This disorder involves problems with the aorta, which is the large blood vessel that distributes blood from the heart to the rest of the body. The aorta can weaken and stretch, causing a bulge in the blood vessel wall (an aneurysm). Stretching of the aorta may also lead to a sudden tearing of the layers in the aorta wall (aortic dissection). Aortic aneurysm and dissection can be life threatening.
ACTA2 gene mutations that are associated with familial TAAD change single protein building blocks (amino acids) in the smooth muscle α-2 actin protein. These changes likely affect the way the protein functions in smooth muscle contraction, interfering with the sarcomeres' ability to prevent arteries from stretching. The aorta, where the force of pumping blood coming directly from the heart is most intense, is particularly vulnerable to this stretching, resulting in the aortic dilatation, aneurysms, and dissections associated with familial TAAD.
Where is the ACTA2 gene located?
Cytogenetic Location: 10q23.3
Molecular Location on chromosome 10: base pairs 88,935,073 to 88,991,389
The ACTA2 gene is located on the long (q) arm of chromosome 10 at position 23.3.
More precisely, the ACTA2 gene is located from base pair 88,935,073 to base pair 88,991,389 on chromosome 10.
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 ACTA2?
You and your healthcare professional may find the following resources about ACTA2 helpful.
- Gene Reviews - Clinical summary (http://www.ncbi.nlm.nih.gov/books/NBK1120)
Genetic Testing Registry - Repository of genetic test information
- GTR: Genetic tests for ACTA2 (http://www.ncbi.nlm.nih.gov/gtr/tests/?term=59%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=%28ACTA2%5BTIAB%5D%29%20OR%20%28AAT6%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%201800%20days%22%5Bdp%5D)
- OMIM - Genetic disorder catalog (http://omim.org/entry/102620)
Research Resources - Tools for researchers
- Atlas of Genetics and Cytogenetics in Oncology and Haematology (http://atlasgeneticsoncology.org/Genes/GC_ACTA2.html)
- GeneCards (http://www.genecards.org/cgi-bin/carddisp.pl?id_type=entrezgene&id=59)
- HGNC Gene Symbol Report (http://www.genenames.org/cgi-bin/gene_symbol_report?q=data/hgnc_data.php&hgnc_id=130)
- NCBI Gene (http://www.ncbi.nlm.nih.gov/gene/59)
What other names do people use for the ACTA2 gene or gene products?
- actin, aortic smooth muscle
- alpha 2 actin
- cell growth-inhibiting gene 46 protein
- growth-inhibiting gene 46
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 ACTA2?
aortic dissection ;
muscle cells ;
You may find definitions for these and many other terms in the Genetics Home Reference
- OMIM: ACTIN, ALPHA-2, SMOOTH MUSCLE, AORTA (http://omim.org/entry/102620)
- El-Hamamsy I, Yacoub MH. Cellular and molecular mechanisms of thoracic aortic aneurysms. Nat Rev Cardiol. 2009 Dec;6(12):771-86. doi: 10.1038/nrcardio.2009.191. Epub 2009 Nov 3. Review. (http://www.ncbi.nlm.nih.gov/pubmed/19884902?dopt=Abstract)
- Gene Review: Thoracic Aortic Aneurysms and Aortic Dissections (http://www.ncbi.nlm.nih.gov/books/NBK1120)
- Grond-Ginsbach C, Pjontek R, Aksay SS, Hyhlik-Dürr A, Böckler D, Gross-Weissmann ML. Spontaneous arterial dissection: phenotype and molecular pathogenesis. Cell Mol Life Sci. 2010 Jun;67(11):1799-815. doi: 10.1007/s00018-010-0276-z. Epub 2010 Feb 14. Review. (http://www.ncbi.nlm.nih.gov/pubmed/20155481?dopt=Abstract)
- Guo DC, Pannu H, Tran-Fadulu V, Papke CL, Yu RK, Avidan N, Bourgeois S, Estrera AL, Safi HJ, Sparks E, Amor D, Ades L, McConnell V, Willoughby CE, Abuelo D, Willing M, Lewis RA, Kim DH, Scherer S, Tung PP, Ahn C, Buja LM, Raman CS, Shete SS, Milewicz DM. Mutations in smooth muscle alpha-actin (ACTA2) lead to thoracic aortic aneurysms and dissections. Nat Genet. 2007 Dec;39(12):1488-93. Epub 2007 Nov 11. Erratum in: Nat Genet. 2008 Feb;40(2):255. (http://www.ncbi.nlm.nih.gov/pubmed/17994018?dopt=Abstract)
- Milewicz DM, Carlson AA, Regalado ES. Genetic testing in aortic aneurysm disease: PRO. Cardiol Clin. 2010 May;28(2):191-7. doi: 10.1016/j.ccl.2010.01.017. Review. (http://www.ncbi.nlm.nih.gov/pubmed/20452526?dopt=Abstract)
- Milewicz DM, Guo DC, Tran-Fadulu V, Lafont AL, Papke CL, Inamoto S, Kwartler CS, Pannu H. Genetic basis of thoracic aortic aneurysms and dissections: focus on smooth muscle cell contractile dysfunction. Annu Rev Genomics Hum Genet. 2008;9:283-302. doi: 10.1146/annurev.genom.8.080706.092303. Review. (http://www.ncbi.nlm.nih.gov/pubmed/18544034?dopt=Abstract)
- Morisaki H, Akutsu K, Ogino H, Kondo N, Yamanaka I, Tsutsumi Y, Yoshimuta T, Okajima T, Matsuda H, Minatoya K, Sasaki H, Tanaka H, Ishibashi-Ueda H, Morisaki T. Mutation of ACTA2 gene as an important cause of familial and nonfamilial nonsyndromatic thoracic aortic aneurysm and/or dissection (TAAD). Hum Mutat. 2009 Oct;30(10):1406-11. doi: 10.1002/humu.21081. (http://www.ncbi.nlm.nih.gov/pubmed/19639654?dopt=Abstract)
- NCBI Gene (http://www.ncbi.nlm.nih.gov/gene/59)
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.