Genetic Testing for Breast Cancer: Myths, Facts and Stats | Myogenes

There is a growing awareness of genetic testing for a wide range of hereditary cancers. This is due, in part, to high profile celebrities like Angelina Jolie who famously underwent preventative breast cancer surgery after discovering she had the BRCA gene mutation, which greatly increases the risk of breast and ovarian cancer.

But, alongside the rise in awareness has come an increase in myths and misunderstandings. So, to mark Breast Cancer Awareness month, starting on 1st October, we have created a myth-busting blog to separate the fact from the ction about genetic testing for breast cancer…

Isn’t it better not to know?

One of the questions we get asked in relation to genetic testing for cancer is “isn’t it better not to know, won’t it just cause unnecessary fear and worry?”

Our view on this is very much “no”. If you know you are at increased risk of any type of cancer, including breast cancer, you can take proactive steps to protect yourself.

This might include regular breast screening, or getting screened at an earlier age than normal, so the disease can be detected in the earliest stages – the earlier you receive a diagnosis, generally the greater your chances of successful treatment.

In some cases, you may be prescribed preventative medication such as tamoxifen or raloxifene, which can lower your chance of developing certain cancers. If you are at increased risk of cancer, close family members may also be at increased risk so they may wish to get tested as well.

If the result is positive, will I definitely get breast cancer?

No, a positive test result doesn’t mean you will get cancer. You might have a significantly increased risk of the disease during your lifetime, which will need to be carefully managed, but a positive result on a genetic test, is not necessarily a diagnosis.

In the same way, a negative test result doesn’t mean you definitely won’t get breast cancer. It just means you have the same risk of developing the cancer as the general population.

  • The lifetime risk of breast cancer for women, without a known risk, is approximately 12%, meaning one in nine women.
  • Women with a BRCA mutation have an increased risk of breast cancer, of approx. 60-90% and for ovarian cancer it is 40-60%.
  • The faulty BRCA gene affects around one in 400 people, however in high risk populations, like those of Ashkenazi Jewish decent, their risk of having the BRCA genetic mutation increases to as high as one in 40 people.
  • If you have a strong family history of cancer but you get a negative result, it is important to remain vigilant, as there may be some genetic mutations that have not yet been identified by scientists.

Only women need to get tested for BRCA mutations

Both men and women with the BRCA mutation are at increased risk of developing cancer. The hereditary breast cancer risk for women is more commonly talked about but the fact is that men can also be affected, it just isn’t as well documented or publicised.

Men carrying BRCA1 or BRCA2 gene mutations are at risk of breast, pancreatic or prostate cancer, as well as melanomas. Other genes also influence and increase the risk for men, for example HOXB13.

Find out more about why men should get tested too.

Genetic mutations can skip a generation

Genetic mutations don’t skip a generation but they don’t always cause cancer so it might appear this way.

I need to have surgery to prevent myself from developing breast cancer

It is important not to rush into anything, particularly something as important as surgery. While preventative surgery is one option, it may not be the only option if you are at high risk of cancer and you will need to talk to your doctor about your choices. For some people, regular screening or preventative medication may be sufficient.

Most breast cancers are hereditary

Actually only around 10% (one in 10) of breast cancers are due to a genetic mutation. This means it is important to know if close members of your family had or have breast cancer, but it also means that most cases of breast cancer are nothing to do with your genes.

BRCA are the only genetic mutations linked to breast cancer

While the BRCA mutations are the main ones linked to breast cancer they are not the only ones. Myogenes genetic test for breast cancer, tests the following genes:


Genetic testing for breast cancer

Genetic testing uses a simple saliva test, which is sent off to the laboratory for analysis. Your doctor will receive a detailed test report, including a personalised health risk management plan.

If you are identified as being at increased risk, you can take proactive steps to manage your health, including having regular screening or, in some cases, preventative medication or surgery.

You may also wish to recommend testing to other close family members who may be at increased risk.

For more information about the Myogenes Hereditary Breast & Ovarian Cancer tests, please contact our team.