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The official name of this gene is “breast cancer 2, early onset.”
BRCA2 is the gene's official symbol. The BRCA2 gene is also known by other names, listed below.
The BRCA2 gene provides instructions for making a protein that acts as a tumor suppressor. Tumor suppressor proteins help prevent cells from growing and dividing too rapidly or in an uncontrolled way.
The BRCA2 protein is involved in repairing damaged DNA. In the nucleus of many types of normal cells, the BRCA2 protein interacts with several other proteins to mend breaks in DNA. These breaks can be caused by natural and medical radiation or other environmental exposures, and they also occur when chromosomes exchange genetic material in preparation for cell division. By helping to repair DNA, the BRCA2 protein plays a critical role in maintaining the stability of a cell's genetic information.
Researchers suspect that the BRCA2 protein has additional functions within cells. For example, the protein may help regulate cytokinesis, which is the step in cell division when the fluid surrounding the nucleus (the cytoplasm) divides to form two separate cells. Researchers are investigating the protein's other potential activities.
The BRCA2 gene belongs to a family of genes called FANC (Fanconi anemia, complementation groups).
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.
Researchers have identified more than 1,800 mutations in the BRCA2 gene. Many of these mutations are associated with an increased risk of breast cancer in both men and women, as well as several other types of cancer. These mutations are present in every cell in the body and can be passed from one generation to the next. As a result, they are associated with cancers that cluster in families. However, not everyone who inherits a mutation in the BRCA2 gene will develop cancer. Other genetic, environmental, and lifestyle factors also contribute to a person's cancer risk.
Most BRCA2 gene mutations lead to the production of an abnormally small, nonfunctional version of the BRCA2 protein from one copy of the gene in each cell. As a result, less of this protein is available to help repair damaged DNA or fix mutations that occur in other genes. As these defects accumulate, they can trigger cells to grow and divide uncontrollably to form a tumor.
More than 30 inherited BRCA2 gene mutations have been found to increase the risk of prostate cancer. Men with these mutations are also more likely to develop prostate cancer at an earlier age and may be at increased risk of having an aggressive form of the disease. They may also be at increased risk for other cancers.
BRCA2 gene mutations likely reduce the BRCA2 protein's ability to repair DNA, allowing potentially damaging mutations to persist in various other genes. The accumulation of damaging mutations can lead to the out-of-control cell growth and division that can result in development of a tumor.
Inherited mutations in the BRCA2 gene also increase the risk of several other types of cancer, including cancers of the ovaries, fallopian tubes, and the lining of the abdomen (peritoneum) in women, as well as pancreatic cancer in both men and women. Inherited BRCA2 gene mutations may also be associated with an increased risk of an aggressive form of skin cancer called melanoma. These mutations impair the ability of the BRCA2 protein to help repair damaged DNA. As defects accumulate in DNA, they can trigger cells to grow and divide without order to form a tumor.
Cytogenetic Location: 13q12.3
Molecular Location on chromosome 13: base pairs 32,314,861 to 32,399,849
The BRCA2 gene is located on the long (q) arm of chromosome 13 at position 12.3.
More precisely, the BRCA2 gene is located from base pair 32,314,861 to base pair 32,399,849 on chromosome 13.
See How do geneticists indicate the location of a gene? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genelocation) in the Handbook.
You and your healthcare professional may find the following resources about BRCA2 helpful.
You may also be interested in these resources, which are designed for genetics professionals and researchers.
See How are genetic conditions and genes named? (http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/naming) in the Handbook.
anemia ; cancer ; cell ; cell division ; cytokinesis ; cytoplasm ; DNA ; gene ; inherited ; melanoma ; mutation ; nucleus ; pancreatic ; peritoneum ; prostate ; protein ; radiation ; susceptibility ; susceptibility gene ; tumor
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
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? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.