Family history of BRCA or related cancers

If there is a history of cancers related to BRCA in your family or family members have an altered BRCA gene, you may worry about what this means for you.

What does it mean if I have a history of BRCA-related cancer in my family?

You may be worried if you have a history of breast, ovarian or other BRCA-related cancer in your family.

  • A strong family history may mean there is an altered gene in your family, but this is not always the case. Around 10% of cancers are thought to be genetic.
  • If a family member's cancer was linked to an altered BRCA gene, the gene and the increased risk can be passed on from mothers and fathers to their children. This is called genetic risk - risk linked to a change in a gene (genetic alteration).
  • If there is an altered BRCA gene in your family, you may or may not have the inherited change that increases your risk of cancer. 
  • Your GP can advise you about this and refer you to a genetics clinic, if necessary.

Are BRCA alterations inherited from your mother or father?

We inherit half our genes from our mother and half from our father. If either parent has a BRCA alteration, each child has a 50% (1 in 2) chance of inheriting this alteration.

 

BRCA Genes mapping image

Can the BRCA gene change skip a generation?

If one of your parents has an altered BRCA gene, you have a 1 in 2 chance of inheriting it. 

  • If you did not inherit the altered BRCA gene, you cannot pass it on to your children. Altered BRCA genes cannot skip a generation.
  • If you do inherit the altered BRCA gene, your risk of cancer is increased, but you may not get cancer. 
  • If you have the altered BRCA gene but you don’t get cancer, you can still pass the gene to your children. If this happens, they too can pass it on, even if they don’t get cancer. This means the gene can be present in different generations, but cancer may not develop in every generation.

How do I find out if cancer in my family is linked to the BRCA gene?

Visit your GP

  • If you’re worried about a family history of cancer, go to your GP. 
  • Your GP will ask you about any members of your family who have had cancer and how old they were when they got it. It is best to find out as much information as you can, before you go to your GP. Write down the information, so you don’t forget. Don’t worry if you don’t know everything. 
  • The GP can refer you to a genetics clinic if they think cancer in your family may be linked to the BRCA gene. 

Thinking and talking about cancer in your family can be upsetting. If you want to talk to someone or need support, you can call our cancer nurses on 1800 200 700.

If you're referred to a genetics clinic

  • If you are referred to a genetics clinic, you may have to wait some time for your appointment.
  • Being referred to a genetics clinic does not mean you will definitely have a genetic test.
  • The first step is to look at your family history to see if cancer in your family may be caused by a BRCA gene alteration. 
  • The genetics clinic will send you a family history questionnaire that you must complete and return. You will not be offered an appointment until you have returned your questionnaire. 
  • At the clinic, you will go through the details of your family history of cancer. 
  • Based on this, the clinic will assess your risk and tell you if they recommend genetic testing or not. 
  • A genetic test uses a sample of blood or spit (saliva). It can look for genetic alterations that may be linked to cancer in your family. 
  • You will talk to a genetic counsellor at the clinic. They can explain all about cancer and genes. They can also give you information about genetic testing and support you in making a decision about testing, if it is recommended for you. 
  • If you are offered testing, it is your decision whether to have a test or not.

 

Genetic testing is free for people who are referred publicly by their GP or other healthcare professional. 

If you have health insurance, you may be covered for testing. 

It is also possible to pay for private genetic testing. 

A family member has a BRCA alteration – what should I do?

  • If you know there is a BRCA alteration in your family, you may or may not have inherited it.
  • If you have inherited the BRCA alteration, you will be at increased risk of cancer. 
  • You can choose to have a genetic test to see if you have inherited BRCA alteration or not. 

I’m scared to find out if I have inherited an altered BRCA gene

Knowing you have an increased risk of cancer can be frightening and you may feel your life will never be the same again. 

On the other hand, knowing the facts can help you take steps to reduce your risk of cancer. It can give you a sense of control.

Remember that a genetic test may also show that you have not inherited the altered gene. This can be a big relief.

If you are referred to a genetics clinic, you can go and still decide not to have genetic testing if it is offered to you. Talking to a genetic counsellor at the clinic will help you to understand everything and help you to make the decision that feels right for you. 

If you have an altered BRCA gene

We have information to support you if a genetic test shows you have inherited an altered BRCA gene. 


Cancer and genes factsheet

Cancer and genes factsheet
Cancer and genes factsheet
Booklet 10 pages 218.8 KB
This factsheet is for people who are worried that cancer might run in their family because a number of relatives have had it. It is also for people who are considering genetic testing.

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