BRIP1

The BRIP1 gene provides instructions for making a protein that is involved in repairing damaged DNA. Within the nucleus of cells, the BRIP1 protein interacts with the protein produced from the BRCA1 gene. These two proteins work together to mend broken strands of DNA, which prevents cells from accumulating genetic damage that can trigger them to divide uncontrollably. Because BRIP1 and BRCA1 help control the rate of cell growth and division, these proteins are described as tumor suppressors.

DNA is arranged in two long strands that form a spiral called a double helix. The BRIP1 protein acts as a helicase, which means that it attaches to particular regions of DNA and temporarily separates the two strands. By unwinding the strands near sites of DNA damage, the BRIP1 protein allows other proteins (such as BRCA1) to reach damaged areas and fix them. 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. By helping repair mistakes in DNA, the BRIP1 protein plays a role in maintaining the stability of a cell's genetic information.

breast cancer - associated with the BRIP1 gene

Recent studies have found that certain inherited mutations in the BRIP1 gene are associated with an increased risk of developing breast cancer. These mutations occur in one copy of the gene in each cell and lead to the production of an abnormally short, nonfunctional version of the BRIP1 protein. If this protein is defective or missing, it is unable to interact with the BRCA1 protein to repair damaged DNA effectively. As defects accumulate in DNA, they can trigger cells to grow and divide uncontrollably and form a tumor.

Researchers have also studied other types of variation in the BRIP1 gene and their potential influence on breast cancer risk. Many of these variations change a single building block (amino acid) used to make the BRIP1 protein. Although some studies found evidence that certain BRIP1 variations are associated with increased breast cancer risk, other studies found no such connection. Overall, it appears that changes in the BRIP1 gene are not a major contributor to the risk of developing breast cancer.

other disorders - caused by mutations in the BRIP1 gene

A condition called Fanconi anemia type J (FA-J) results from two mutated copies of the BRIP1 gene in each cell. These mutations severely reduce or eliminate the activity of the BRIP1 protein. Without enough of this protein, breaks in DNA are not repaired normally and genetic damage can build up over time. As a result, people with Fanconi anemia are prone to several types of cancer, including cancers of blood-forming tissue (leukemias). They are also at an increased risk of developing solid tumors, particularly of the head, neck, skin, and reproductive organs. Additionally, people with Fanconi anemia experience bone marrow suppression, which causes an abnormal reduction in the number of red blood cells, white blood cells, and blood platelets made by the bone marrow. The reduced production of red blood cells causes the anemia characteristic of this disorder.

Genetics Home Reference provides information about Fanconi anemia, which is also associated with changes in the BRIP1 gene.