What is the normal function of the BARD1 gene?
The BARD1 gene provides instructions for making a protein that helps control cell growth and division. Within the nucleus of cells, the BARD1 protein interacts with the protein produced from the BRCA1 gene. Together, these two proteins act as tumor suppressors, which means they prevent cells from growing and dividing too rapidly or in an uncontrolled way.
The BARD1 and BRCA1 proteins work together to repair damaged DNA. Research has shown that the BARD1 protein binds to the BRCA1 protein, which stabilizes both proteins and targets the BRCA1 protein to sites where DNA strands are broken. Breaks in DNA can be caused by natural and medical radiation or other environmental exposures, but also occur when chromosomes exchange genetic material in preparation for cell division. By helping repair damaged DNA, the BARD1 and BRCA1 proteins play a critical role in maintaining the stability of a cell's genetic information.
Studies suggest that the BARD1 protein also has functions apart from its partnership with the BRCA1 protein. The BARD1 protein interacts with another protein, p53 (which is produced from the TP53 gene) to promote controlled cell death (apoptosis) and regulate cell division. Other potential functions of the BARD1 protein are under study.