RAD51

The RAD51 gene provides instructions for making a protein that is essential for repairing damaged DNA. Breaks in DNA can be caused by natural and medical radiation or other environmental exposures, and also occur when chromosomes exchange genetic material in preparation for cell division. The RAD51 protein binds to the DNA at the site of a break and encases it in a protein sheath, which is an essential first step in the repair process.

In the nucleus of many types of normal cells, the RAD51 protein interacts with many other proteins, including BRCA1 and BRCA2, to fix damaged DNA. The BRCA2 protein regulates the activity of the RAD51 protein by transporting it to sites of DNA damage in the nucleus. The interaction between the BRCA1 protein and RAD51 is less clear, although research suggests that BRCA1 may also activate RAD51 in response to DNA damage. By helping repair DNA, these three proteins play a role in maintaining the stability of a cell's genetic information.

breast cancer - associated with the RAD51 gene

Several alterations in the RAD51 gene have been associated with an increased risk of developing breast cancer. Some of these genetic changes appear to modify breast cancer risk in women who also carry a mutation in the BRCA1 or BRCA2 gene. Because the proteins produced from these three genes work together to fix damaged DNA, mutations likely disrupt the normal repair process. As defects accumulate in DNA, they can allow cells to grow and divide uncontrollably and form a tumor.