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Genetics Home Reference: your guide to understanding genetic conditions     A service of the U.S. National Library of Medicine®


Reviewed July 2012

What is the official name of the HRAS gene?

The official name of this gene is “Harvey rat sarcoma viral oncogene homolog.”

HRAS is the gene's official symbol. The HRAS gene is also known by other names, listed below.

What is the normal function of the HRAS gene?

The HRAS gene provides instructions for making a protein called H-Ras that is involved primarily in regulating cell division. Through a process known as signal transduction, the H-Ras protein relays signals from outside the cell to the cell's nucleus. These signals instruct the cell to grow or divide. The H-Ras protein is a GTPase, which means it converts a molecule called GTP into another molecule called GDP. The H-Ras protein acts like a switch, and it is turned on and off by GTP and GDP molecules. To transmit signals, the protein must be turned on by attaching (binding) to a molecule of GTP. The H-Ras protein is turned off (inactivated) when it converts GTP to GDP. When the protein is bound to GDP, it does not relay signals to the cell's nucleus.

The HRAS gene belongs to a class of genes known as oncogenes. When mutated, oncogenes have the potential to cause normal cells to become cancerous. The HRAS gene is in the Ras family of oncogenes, which also includes two other genes: KRAS and NRAS. The proteins produced from these three genes are GTPases. These proteins play important roles in cell division, the process by which cells mature to carry out specific functions (cell differentiation), and the self-destruction of cells (apoptosis).

How are changes in the HRAS gene related to health conditions?

Costello syndrome - caused by mutations in the HRAS gene

At least 15 mutations in the HRAS gene have been identified in people with Costello syndrome, a rare condition that affects many parts of the body and increases the risk of developing cancerous and noncancerous tumors. The mutations change single protein building blocks (amino acids) in a critical region of the H-Ras protein. The most common mutation accounts for more than 80 percent of all cases of Costello syndrome; it replaces the amino acid glycine with the amino acid serine at protein position 12 (written as Gly12Ser or G12S).

The HRAS gene mutations that cause Costello syndrome lead to the production of an H-Ras protein that is abnormally turned on (active) in cells throughout the body. Instead of triggering cell growth in response to signals from outside the cell, the overactive protein directs cells to grow and divide constantly. This uncontrolled cell division can result in the formation of noncancerous and cancerous tumors. Researchers are uncertain how mutations in the HRAS gene cause the other features of Costello syndrome (such as intellectual disability, distinctive facial features, and heart problems), but many of the signs and symptoms probably result from cell overgrowth and abnormal cell division.

bladder cancer - associated with the HRAS gene

Some gene mutations are acquired during a person's lifetime and are present only in certain cells. These changes, which are called somatic mutations, are not inherited. Somatic HRAS gene mutations that occur in bladder cells have been associated with some cases of bladder cancer. A particular mutation has been identified in a significant percentage of bladder tumors; this mutation replaces the amino acid glycine with the amino acid valine at protein position 12 (written as Gly12Val or G12V). As a result of this genetic change, the altered H-Ras protein becomes continuously active within the cell. The overactive H-Ras protein directs the cell to grow and divide abnormally, leading to uncontrolled cell division and the formation of a tumor. Mutations in the HRAS gene also have been associated with the progression of bladder cancer and an increased risk of tumor recurrence after treatment.

other cancers - associated with the HRAS gene

Somatic mutations in the HRAS gene are probably involved in the development of several additional types of cancer. These mutations lead to a version of the H-Ras protein that is always active and can direct cells to grow and divide without control. Studies suggest that HRAS gene mutations may be common in thyroid and kidney cancers. Increased activity (expression) of the HRAS gene has also been reported in other types of cancer.

Where is the HRAS gene located?

Cytogenetic Location: 11p15.5

Molecular Location on chromosome 11: base pairs 532,241 to 535,560

The HRAS gene is located on the short (p) arm of chromosome 11 at position 15.5.

The HRAS gene is located on the short (p) arm of chromosome 11 at position 15.5.

More precisely, the HRAS gene is located from base pair 532,241 to base pair 535,560 on chromosome 11.

See How do geneticists indicate the location of a gene? ( in the Handbook.

Where can I find additional information about HRAS?

You and your healthcare professional may find the following resources about HRAS helpful.

You may also be interested in these resources, which are designed for genetics professionals and researchers.

What other names do people use for the HRAS gene or gene products?

  • C-H-RAS
  • Harvey murine sarcoma virus oncogene
  • HRAS1
  • Oncogene, G-RAS
  • RASH1
  • Transformation gene: Oncogene HaMSV
  • Transforming protein P21/H-RAS-1 (C-H-RAS)
  • v-Ha-ras Harvey rat sarcoma viral oncogene homolog

See How are genetic conditions and genes named? ( in the Handbook.

What glossary definitions help with understanding HRAS?

acids ; amino acid ; apoptosis ; cancer ; carcinoma ; cell ; cell division ; class ; critical region ; differentiation ; disability ; gene ; glycine ; GTP ; inherited ; kidney ; molecule ; mutation ; nucleus ; oncogene ; progression ; protein ; RAS ; sarcoma ; serine ; signal transduction ; syndrome ; thyroid ; transduction ; transformation ; tumor ; valine ; virus

You may find definitions for these and many other terms in the Genetics Home Reference Glossary (


  • Aoki Y, Niihori T, Kawame H, Kurosawa K, Ohashi H, Tanaka Y, Filocamo M, Kato K, Suzuki Y, Kure S, Matsubara Y. Germline mutations in HRAS proto-oncogene cause Costello syndrome. Nat Genet. 2005 Oct;37(10):1038-40. Epub 2005 Sep 18. (
  • Colicelli J. Human RAS superfamily proteins and related GTPases. Sci STKE. 2004 Sep 7;2004(250):RE13. Review. (
  • Estep AL, Tidyman WE, Teitell MA, Cotter PD, Rauen KA. HRAS mutations in Costello syndrome: detection of constitutional activating mutations in codon 12 and 13 and loss of wild-type allele in malignancy. Am J Med Genet A. 2006 Jan 1;140(1):8-16. (
  • Giehl K. Oncogenic Ras in tumour progression and metastasis. Biol Chem. 2005 Mar;386(3):193-205. Review. (
  • Gripp KW, Innes AM, Axelrad ME, Gillan TL, Parboosingh JS, Davies C, Leonard NJ, Lapointe M, Doyle D, Catalano S, Nicholson L, Stabley DL, Sol-Church K. Costello syndrome associated with novel germline HRAS mutations: an attenuated phenotype? Am J Med Genet A. 2008 Mar 15;146A(6):683-90. doi: 10.1002/ajmg.a.32227. (
  • Gripp KW, Lin AE, Stabley DL, Nicholson L, Scott CI Jr, Doyle D, Aoki Y, Matsubara Y, Zackai EH, Lapunzina P, Gonzalez-Meneses A, Holbrook J, Agresta CA, Gonzalez IL, Sol-Church K. HRAS mutation analysis in Costello syndrome: genotype and phenotype correlation. Am J Med Genet A. 2006 Jan 1;140(1):1-7. (
  • Gripp KW, Stabley DL, Nicholson L, Hoffman JD, Sol-Church K. Somatic mosaicism for an HRAS mutation causes Costello syndrome. Am J Med Genet A. 2006 Oct 15;140(20):2163-9. (
  • Kerr B, Delrue MA, Sigaudy S, Perveen R, Marche M, Burgelin I, Stef M, Tang B, Eden OB, O'Sullivan J, De Sandre-Giovannoli A, Reardon W, Brewer C, Bennett C, Quarell O, M'Cann E, Donnai D, Stewart F, Hennekam R, Cavé H, Verloes A, Philip N, Lacombe D, Levy N, Arveiler B, Black G. Genotype-phenotype correlation in Costello syndrome: HRAS mutation analysis in 43 cases. J Med Genet. 2006 May;43(5):401-5. Epub 2006 Jan 27. (
  • NCBI Gene (
  • Oxford G, Theodorescu D. The role of Ras superfamily proteins in bladder cancer progression. J Urol. 2003 Nov;170(5):1987-93. Review. (
  • Rauen KA. HRAS and the Costello syndrome. Clin Genet. 2007 Feb;71(2):101-8. Review. (
  • Sol-Church K, Stabley DL, Nicholson L, Gonzalez IL, Gripp KW. Paternal bias in parental origin of HRAS mutations in Costello syndrome. Hum Mutat. 2006 Aug;27(8):736-41. (
  • Wolff EM, Liang G, Jones PA. Mechanisms of Disease: genetic and epigenetic alterations that drive bladder cancer. Nat Clin Pract Urol. 2005 Oct;2(10):502-10. Review. (


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 healthcare professional. See How can I find a genetics professional in my area? ( in the Handbook.

Reviewed: July 2012
Published: March 23, 2015