When actress Angelina Jolie announced she underwent a preventive double mastectomy due to a BRCA gene mutation, she significantly increased awareness for genetic testing as a tool in the fight against breast cancer. But is genetic testing right for everyone? To make an informed decision, it's important to know the risk factors associated with inheriting the mutated BRCA gene and other facts related to testing.
According to the National Cancer Institute, about 12 percent of women born in the U.S. will develop breast cancer during the course of their lives. However, women who have a specific mutated BRCA gene are at a much higher risk. Fifty-five to 65 percent of women who inherit a harmful BRCA1 mutation and around 45 percent of women who inherit a harmful BRCA2 mutation will develop breast cancer by age 70.
Who is at risk for inheriting the BRCA gene?
What are the odds you have inherited the mutated gene? It is estimated that from one in 400 to one in 800 women carry the BRCA1 or BRCA2 gene. The prevalence of what some call the "breast cancer gene" increases among some ethnic groups. In fact, one out of just 40 Ashkenazi Jewish men and women have a BRCA1 or BRCA2 mutation. Like all genes, we inherit them from our parents. If one parent has the gene, there is a 50 percent chance it will be passed on to their children.
But because the mutated BRCA gene is rare, most doctors recommend testing only when a strong family history suggests otherwise. Several screening tools are used to evaluate the possible presence of the gene:
- A strong hereditary history of breast cancer, particularly in close relatives — mother, sister, daughter, grandmother, aunt, niece or first cousin — at or under age 50
- A known BRCA1 or BRCA2 gene mutation among family members
- A personal history of breast or ovarian cancer
- A close family member diagnosed with ovarian cancer
- Being of Ashkenazi Jewish descent
"It's important to note that only 5 to 10 percent of breast cancers in this country are attributed to inherited gene mutations," says Dr. Reema Batra, a board-certified oncologist affiliated with Sharp Grossmont Hospital. "Patients should talk to their physician who can provide the best advice based on individual needs and medical history."
A simple blood test for a complicated gene
The BRCA1/BRCA2 test itself is a simple blood test that uses DNA analysis to detect the susceptibility of mutation in the genes. Along with the test, a genetic counselor will review family and medical history, assess one's cancer risk and discuss the implications of a positive or negative result.
"For some women, knowing the test result is empowering because it allows them to make informed health care decisions about the future," says Dr. Batra.
"However, it's important to note that while there's no medical risk associated with the test itself, the emotional consequences related to testing could prompt feelings of anxiety, sadness or depression along with uncertainty and concern about family members' potential reactions to the outcome," says Dr. Batra.
What is certain is that early screening is the best way for a woman to take charge of her personal health and to lower the risk of breast cancer.
Dr. Batra offers a few other suggestions for maintaining health and overall well-being:
- Get an annual breast cancer screening; for most women this begins at age 40
- Be physically active and get plenty of exercise
- Reduce your lifetime weight gain by limiting your calories
- Practice meditation, do yoga or find other ways to reduce stress
- Avoid or limit your alcohol intake
- Avoid smoking
If you think genetic testing is right for you or a loved one, contact your doctor and discuss your concerns. Millions of women are surviving breast cancer thanks in part to early detection, improvements in treatment and new technology, including genetic testing.