BRCA gene test is done to analyze the DNA to identify harmful changes in either of the breast cancer susceptibility genes – BRCA1 and BRCA2.
Those with inherent mutations of these genes are at a greater risk of developing breast cancer and ovarian cancer.
Everyone has BRCA1 and BRCA2 genes. These genes when working properly act as tumor suppressors and prevent the cells from growing out of control. The mutations of these genes affect their tumor suppressor duty and increase the risk of cancer.
BRCA Gene Mutation and Cancer Risk
Along with breast cancer and ovarian cancer that are well known to be associated with BRCA gene mutations, there are other types of cancer too that can be caused by the mutation, they include:
- Fallopian tube cancer
- Primary peritoneal cancer
- Prostate cancer
- Pancreatic cancer
Melanoma has also been identified as being connected with BRCA gene mutations.
Which Gene Mutation Has a Greater Cancer Risk?
Both BRCA 1 and BRCA2 increase the risk of developing breast and ovarian cancer, but the percentage of risk varies for both.
According to the National Cancer Institute, there are 55 to 72% chances of developing breast cancer with BRCA1 mutation by 80 years of age, while the chances are only 45 to 69 percent with BRCA2 gene mutations.(1)
For ovarian cancer, the risk is 39-44% with BRCA1 mutation while 11-17% with a BRCA2 mutation.
Who is More At Risk of BRCA Gene Mutation?
People with close family members who’ve had breast or ovarian cancer have a greater risk of being BRCA-positive. There are also other less obvious groups that carry an increased risk of BRCA mutation.(2) These groups include:
- Those having relatives who developed breast cancer before 50 years of age
- Those who, themselves developed breast cancer before 50 years of age
- Those with a male relative with breast cancer
Women of Ashkenazi Jewish descent are more likely to have BRCA gene mutations. According to the Center for Disease Control and Prevention, 1 in 40 Ashkenazi Jewish women have BRCA mutation.(3) It advises Ashkenazi Jewish women with first and second-degree relatives of the same side of the family with breast or ovarian cancer to consider genetic counseling.
Risk Associated With BRCA Gene Testing
There is no medical risk associated with BRCA gene testing other than light-headedness, bleeding, and bruising on having the blood drawn.
Those tested positive for BRCA mutations may face the following symptoms:
- Feelings of sadness, depression, anxiety and anger
- Concerns over possible insurance discrimination
- Strained family relationships
- Difficult decisions about preventive measured and long-term consequences
- A feeling of getting cancer
A genetic counselor can help a person get through the feeling and provide support to the patient and the family throughout the process.
What Does a Negative Test Result Mean?
A negative test result means there is no BRCA gene mutation. It can be a true negative test only if a person does not carry a BRCA mutation that has already been identified in a relative. For others, however, assessing the cancer risk is still difficult.
A negative test does not mean that a person will never get cancer. The risk of suffering from any type of cancer is the same as that for the general population.
