The Differences Between BRCA1 & BRCA2

Several ongoing studies seek to improve techniques for detecting, treating and preventing cancer in BRCA1 and BRCA2 mutation carriers. As knowledge in these areas continues to expand, genetic counseling methods and outcomes have improved.

BRCA Genes

• Breast cancer susceptibility genes (BRCA) are tumor suppressors and function to ensure cellular DNA stability as well as prevent tumor cellular growth. If these genes are mutated and thus malfunctioning, there is an increased chance of cancer development. The BRCA genes have been specifically associated with hereditary breast and ovarian cancer. The risk of developing these cancers is tied to deleterious BRCA gene mutations.

BRCA1 and BRCA2 Mutations' Effect on Cancer Risk

• According to the National Cancer Institute, not all gene mutations are considered to be harmful. Some mutations may be beneficial, whereas others may have no obvious effect. Harmful mutations can increase a person's risk of developing a disease, such as cancer.

  Although the overall risk for breast and ovarian cancer development is increased with either BRCA1 or BRCA2 mutations, there are also other cancer risks depending on which gene is mutated.

BRCA Genes in Women

• In women, BRCA1 mutations are also associated with cervical, uterine, pancreatic and colon cancer development. BRCA2 mutations in women are closely associated with increased risk of pancreatic, stomach, gallbladder and bile duct cancers as well as certain melanomas.

BRCA Genes in Men

• In men, harmful BRCA1 mutations are associated with increased risk of testicular, pancreatic and breast cancers as well as early-onset prostate cancer. Interestingly, men with breast, pancreatic and prostate cancers typically have a stronger association with a harmful BRCA2 mutation. Therefore, both gene mutations carry the risk, but it appears the higher association is with BRCA2 mutation.