This information explains how having a mutation in the ATM gene may affect you and your family.
In this resource, the word “family” means people related to you by blood. They’re not related to you through marriage or adoption. We also call these family members your blood relatives.
Your ATM gene normally helps prevent cancers. A mutation in this gene causes it to stop working like it should.
It is important to understand that having a mutation in this gene does not mean you will definitely develop cancer. It means that you have an increased risk of developing certain types of cancers. The type of cancer can vary among people who have mutations in this gene, even within the same family.
What is my cancer risk if I have an ATM mutation?
An ATM mutation increases your risk for breast cancer. It can also increase your risk for pancreatic cancer, but this is less common.
An ATM mutation may also increase your risk for ovarian and prostate cancer, but more research is needed for us to better understand these risks. Your genetic counselor will give you more information about what we know so far and what it means for you.
While an ATM mutation means you have a somewhat higher risk of developing cancer than the average person, it may not fully explain why your blood relatives have cancer.
As we learn more about these mutations, we may learn they increase the risk for other types of cancers. Your genetic counselor will give you more information about your cancer risk if you have a mutation.
What can I do about my cancer risk if I have an ATM mutation?
Your genetic counselor will review your results. They will talk with you about what cancer your mutation is linked to. As we research these mutations, we may learn they raise the risk for other types of cancers.
Your genetic counselor will also review your personal and family history of cancer and give you cancer screening recommendations. They may recommend you start having cancer screenings at a younger age or have them more often than most people. They may also suggest you get specialized screenings to help find cancer as early as possible.
Some examples of these cancer screenings include having breast magnetic resonance imaging (MRI) scans and mammograms (X-rays of your breast).
They may also talk with you about having surgery to remove your ovaries to prevent ovarian cancer. If you decide to have surgery, talk with your genetic counselor about the right time to have it. Surgery to remove ovaries affects fertility (your ability to have biological children). If you plan to have biological children, your genetic counselor can talk with you about your options.
Your genetic counselor will also talk with you about whether there are any other screening or prevention options that may be right for you.
What does an ATM mutation mean for my blood relatives?
If you have a mutation, your biological parents, siblings, and children each have a 50% chance of having the same mutation. Your distant family members may also be at risk for having the same mutation.
Males and females have an equal chance of passing down a mutation in their family. You only need to inherit a mutation from one parent to have an increased risk for cancer.
Your genetic counselor will review your family history and talk with you about whether they recommend genetic testing for your blood relatives.
What does this mean for family planning?
If you have an ATM mutation and plan to have children, there are options to prevent your children from inheriting the mutation. You may want to consider discussing these options especially if both you and your partner have an ATM mutation.
If you both have a mutation in the ATM gene, which is rare, there’s a chance your child could be born with a serious condition called ataxia-telangiectasia (uh-TAK-see-uh-teh-LAN-jee-ek-TAY-zhuh), or AT. AT is a rare disorder that affects the nervous system, immune system, and other body systems. If you already have children, it’s unlikely they have AT since this is usually diagnosed early in life. For more information about genetic testing and family planning, talk with your genetic counselor.
What happens if I do not have a mutation?
If you do not have a mutation or if we find a variant of uncertain significance (VUS), your genetic counselor will review your personal and family history of cancer. They’ll talk with you about the general cancer screening guidelines you should follow.
A VUS is a change in a gene, but we don’t yet know if it is linked with a higher risk for cancer. Most VUS are eventually found to be normal changes that do not affect your health.