Family history of breast cancer and inherited genes

Referral to a specialist

Your GP will refer you to a specialist breast clinic or genetics clinic for assessment if you have any of the following:

• one first degree female relative diagnosed with breast cancer aged younger than 40 (a first degree relative is your parent, brother or sister, or your child)

• one first degree male relative diagnosed with breast cancer at any age

• one first degree relative with cancer in both breasts where the first cancer was diagnosed aged younger than 50

• two first degree relatives, or one first degree and one second degree relative, diagnosed with breast cancer at any age (second degree relatives are aunts, uncles, nephews, nieces, grandparents, and grandchildren)

• one first degree or second degree relative diagnosed with breast cancer at any age and one first degree or second degree relative diagnosed with ovarian cancer at any age (one of these should be a first degree relative)

• three first degree or second degree relatives diagnosed with breast cancer at any age

Your GP should also refer you if you have one first degree or second degree relative diagnosed with breast cancer when they were older than 40 years and one of the following:

• the cancer was in both breasts (bilateral)

• the cancer was in a man

• ovarian cancer

• Jewish ancestry

• sarcoma (cancer of the bone or soft tissue) in a relative younger than age 45 years

• a type of brain tumour called glioma or childhood adrenal cortical carcinomas

• complicated patterns of multiple cancers diagnosed at a young age

• two or more relatives with breast cancer on your father's side of the family

Read NICE guidance about on increased risk due to family history

Breast cancer genes

If you have a very strong family history of certain cancers, there might be a faulty ​gene​ in your family that increases your risk of breast cancer. We know about several gene faults that can increase breast cancer risk and there are tests for some of them.

Genes that increase the risk of breast cancer are BRCA1 and BRCA2. BRCA stands for BReast CAncer gene. Everyone has BRCA1 and BRCA2. These genes stop cells in our body from growing and dividing out of control. If there is a ​fault (mutation)​ in these genes, it means that cells can grow out of control. This can lead to developing several cancers including breast cancer.

Other genes that could increase your risk of developing breast cancer if they have a fault include:

• TP53 gene

• PALB2 gene

• ATM gene

• CHEK2 gene

• STK11 gene

• PTEN gene

Find out more about breast cancer genes

Having one of these faulty genes means that you are more likely to get breast cancer than someone who doesn’t. But it is not a certainty.

Remember that most breast cancers happen by chance. Researchers estimate that only around 5 to 10 out of 100 breast cancers (5 to 10%) are caused by an inherited faulty gene.

Read about testing for inherited cancer genes