NHGRI logo
Chromosome spread


updated: June 19, 2024


BRCA1 and BRCA2 are the first two genes found to be associated with inherited forms of breast cancer and ovarian cancer. People with mutations in either BRCA1 or BRCA2 have a much higher risk for developing breast, ovarian or other types of cancer than those without mutations in the genes. Both BRCA1 and BRCA2 normally act as tumor suppressors, meaning they help to regulate cell division. Most people have two active copies of these genes. When one of the two copies becomes inactive due to an inherited mutation, a person’s cells are left with only one copy. If this remaining copy also becomes inactivated, then uncontrolled cell growth results, which leads to breast, ovarian or other types of cancer.


BRCA1 and BRCA2. Everyone actually has a BRCA1 and 2 gene. And in their unmutated form, they carry out very important functions related to keeping your genome healthy and intact.

Lawrence Brody
Lawrence Brody, Ph.D.


Division of Genomics and Society