As many know, inherited traits are passed down through genes, and each person has two copies of genes as they inherit them from each parent. Because each parent passes down one half of their genes, a parent’s genetic traits have a 50 percent chance of being passed down to their children.
The BRCA gene is one of the genes that is inherited from parents. Everyone has the BRCA1 and BRCA2 gene and, despite the fact that BRCA stands for “breast cancer,” the gene itself does not cause breast cancer. In fact, the true role of the genes is to prevent cancer by repairing DNA breaks that may lead to the disease along with uncontrolled growth of tumors. In most people, BRCA genes are known as the tumor suppressor genes.
In about 0.25 percent of the population, the BRCA1 or BRAC2 gene is mutated. This occurs when the DNA that makes up the gene somehow becomes damaged. When one of the genes is mutated, it may no longer be effective at preventing cancer. Because of the mutation, there is an increased risk of cancer or a tendency to develop it at a younger age. The carrier of the gene can also pass it along to their children.
BRCA mutations can occur in both men and women. In most cases, men are silent carriers while women are more likely to develop cancer. Women with a mutation in the BRCA1 gene are at an increased risk of breast cancer, including triple-negative breast cancer which is aggressive and challenging to treat. Men with a BRCA2 mutation have a six percent chance of experiencing breast cancer, compared to a one percent lifetime risk with a mutated BRCA2.
The only way to know if you have a BRCA mutation is through genetic testing. Today, it is easier to obtain testing for BRCA mutations and once the doctor identifies that it exists, it is easier to plan therapy.
A BRCA1 mutation means that you have a 60 to 70 percent chance of developing breast cancer in your lifetime. A BRCA2 mutation has a risk of 55 to 70 percent for breast cancer. It may also put you at risk of other cancers including fallopian tube, prostate and pancreatic. Someone with the mutation will need to undergo additional screenings. Johns Hopkins recommends cancer screenings starting at 25 with yearly MRIs and mammograms at the age of 30.
For those who are past childbearing years, prophylactic mastectomy and hysterectomy is discussed. Although such measures are not always necessary, it does lower the risk of cancer which increases as you get older.
A BRCA mutation is passed down from one parent to a child. The mutation does not skip generations. Children who do not inherit their parents BRCA mutation cannot pass it on to their children. Not everyone who has the BRCA mutation develops cancer, but they can still pass the mutation on to their children. If the parent who has the mutation never develops cancer and was never tested for the mutation, but a child does, it may appear that the mutation skipped a generation.
If you have a close relative who has developed breast cancer at a young age or a history of prostate, pancreatic or ovarian cancer, it is recommended you talk to your doctor about genetic testing.
