BRCA2: Encyclopedia II - BRCA2 - Related conditions

BRCA2 - Related conditions

Certain variations of the BRCA2 gene cause an increased risk for breast cancer. Researchers have identified about 450 mutations in the BRCA2 gene, many of which cause an increased risk of cancer. BRCA2 mutations are usually insertions or deletions of a small number of DNA base pairs (the building material of chromosomes) in the gene. As a result of these mutations, the protein product of the BRCA2 gene is abnormally short and does not function properly. Researchers believe that the defective BRCA2 protein is unable to help fix mutations that occur in other genes. As a result, mutations build up and can cause cells to divide in an uncontrolled way and form a tumor.

People who have two mutated copies of the BRCA2 gene have one type of Fanconi anemia. This condition is caused by extremely reduced levels of the BRCA2 protein in cells, which allows the accumulation of damaged DNA. Patients with Fanconi anemia are prone to several types of leukemia (a type of blood cell cancer); solid tumors, particularly of the head, neck, skin, and reproductive organs; and bone marrow suppression (reduced blood cell production that leads to anemia).

In addition to breast cancer in men and women, mutations in BRCA2 also lead to an increased risk of ovarian, prostate, and pancreatic cancers. In particular, mutations in the central part of the gene have been associated with a higher risk of ovarian cancer and a lower risk of prostate cancer than mutations in other parts of the gene. As mutations build up, they can cause cells to divide in an uncontrolled way and form a tumor. Several other types of cancer have also been seen in families with BRCA2 mutations.

Adapted from the Wikipedia article "Related conditions", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki