The BRCA gene mutation. Maybe you have it. Maybe a family member has it. Maybe you’ve heard about it because Angelina Jolie has it. No matter how you know about it, it’s important to know what it is because there’s a lot of misinformation out there. Here are the facts:
What is the BRCA gene mutation anyway?
In order to best answer that, we’re going to have to drop some science on you. We promise to keep it simple.
Most genes come in pairs, and we inherit one copy from each parent, so all people have two copies of the BRCA1 and BRCA2 genes (“BRCA” is an abbreviation for “BReast CAncer gene”). BRCA genes have been widely accused of being the jerk that increases the risk of cancer. But that’s not accurate. Instead, it is actually the mutation of this gene that causes the increased risk of breast, ovarian, fallopian tube, and other types of cancers. BRCA genes themselves are badass — it is their job to help prevent cancer!
Cancers are caused by damage to the DNA in cells, and the BRCA genes produce proteins to help repair damaged DNA. These proteins (often referred to as tumor suppressor genes) help prevent uncontrolled cell growth and keep abnormal cells from turning into cancer.
If either parent has an inherited, damaged (aka mutated) BRCA gene, there is a 50% chance they will then pass it on to their children. With one of their two copies of the BRCA gene not working properly, carriers of this mutation go into life with only half the defense against suppressing tumors, which is why cancer tends to develop earlier for them.
- Approximately 1 in 400 carry a BRCA1 or BRCA2 gene mutation, and 10% of all breast cancer cases are caused by these mutations
- The chance for a female without inherited mutations to develop breast cancer in her lifetime is 12%
- The chance for a female with the BRCA1 mutation to develop breast cancer in her lifetime before age 70 is 55%-80%
- The chance for a female with the BRCA2 mutation to develop breast cancer in her lifetime before age 70 is 40%-60%
- BRCA carriers who have had breast cancer have an increased risk of developing breast cancer in the opposite (or contralateral) breast, along with an increased risk of recurrence in the initial breast locally, or occurring in another part of the body (metastasis).
- BRCA gene mutations are more prevalent in certain ethnic or racial populations such as Ashkenazi Jewish descent, African American, Icelandic, Dutch, and Norwegian.
It is also crucial to note that the BRCA gene mutation comes with a high risk of developing ovarian cancer. The chance for the average female to develop ovarian cancer in her lifetime is 1-2%, BRCA1 carriers have a 35-45% chance, and BRCA2 carriers have a 12-20% chance (and may be at risk for other cancers). For more on ovarian cancer and the BRCA gene, visit this website.
Should I get tested for the BRCA mutation?
It is recommended you get tested if you have a substantial personal or family history of breast or ovarian cancer, such as:
- You have one or more relatives on the same side of the family with:
- A history of breast cancer before age 50
- Ovarian cancer at any age
- Male breast cancer
- A known BRCA mutation
- Triple negative breast cancer
- A history of both breast and ovarian cancer in the family or in a single relative
- You have two or more relatives with a history of:
- Prostate cancer, pancreatic cancer, or BRCA associated-cancer
- Breast cancer at any age
- You have a personal history of:
- Breast cancer diagnosed before age 45
- Triple negative breast cancer
- A second primary breast cancer
- Ovarian cancer
- You are of Ashkenazi Jewish Eastern European heritage; 1 in 40 women with this heritage carrier the BRCA gene mutation.
- You are of Icelandic, Dutch, or Norwegian descent
- You are Black and have been diagnosed with breast cancer at age 35 or younger
If any of these apply to you, speak to your doctor about testing, or consider making an appointment with a genetic counselor. Most insurance companies will cover the blood test if you have a significant personal and family history.
For parents who carry this gene mutation and want to see if they have passed it on to their children, testing is not recommended under 18, as that age group is considered at lower risk to develop BRCA-related cancer, nor are there approved risk reduction interventions for that group.
A quick word of warning: some genealogy sites offer BRCA saliva specimen genetic testing. Personally, I have the BRCA1 gene mutation… but testing on one of these sites yielded a different result. Thank goodness I got a second opinion. Needless to say, we strongly urge you to leave genealogy testing to family-tree fun and leave medical testing to medical professionals.