What does the latest study mean for people with Shetland ancestry?

Research done by the VIKING Genes study with the NHS Grampian Clinical Genetics clinic has found that 1 in 40 people who have four grandparents from Whalsay share the same variant in the gene BRCA2. The variant increases the chance of developing breast, ovarian and prostate cancers.

The NHS North of Scotland Genetics Service has seen the same variant in the BRCA2 gene in several families from around Shetland with breast, ovarian and prostate cancer. Prof Jim Wilson’s VIKING I study allowed analysis of how common this gene variant is and where it came from. They found that almost all the people with the gene variant have Whalsay ancestors.

How does BRCA2 link to cancer?

We have two copies of most of the genes in our body – one from our mother and one from our father. Most breast, ovarian and prostate cancers occur by chance damage to certain genes.

However, some people inherit a variant in one copy of a particular gene that can increase their chance of developing breast, ovarian or prostate cancer.

One of these cancer predisposing genes is BRCA2, another is BRCA1. Around one in 260 people across the UK have a BRCA1 or BRCA2 gene variant that gives them a higher lifetime chance of developing breast, ovarian, and other cancers. Not everyone with the variant gets cancer.

How are people with BRCA2 variants looked after?

Women with BRCA2 variants have a higher chance of getting breast and / or ovarian cancer. They are offered more sensitive and more frequent breast screening using MRI, from the age of 30. They can also choose to have risk-reducing surgery, such as mastectomy and / or removal of the ovaries once their family is completed. Men with BRCA2 variants have an increased chance of getting prostate cancer and also have a small increased chance of breast cancer. Men with BRCA2 variants are offered annual blood tests to look for prostate cancer early. Many men with BRCA2 variants do not get cancer, but men and women with the gene variant can pass it onto their children.

People with BRCA2 variants diagnosed with cancer may be offered BRCA-targeted chemotherapy as part of their treatment.

Who can be tested for the Whalsay BRCA2 gene variant right now?

A test is currently available to relatives of people with the known BRCA2 variant as standard NHS care.

You can also request an NHS genetic risk assessment for testing if you have at least one Whalsay born grandparent AND

1. have had ovarian, breast or prostate cancer OR
2. have a parent, child, sibling, nephew, niece, uncle, aunt or grandparent who has had ovarian, breast or prostate cancer.

Are there plans to expand the availability of testing?

Not at present, until the case for expansion can be made and further funding is raised.

I took part in one of the VIKING Genes studies. How can I find out if I have the BRCA2 gene variant?

Everyone with the variant who took part in VIKING I and asked to receive their results was sent letters in 2023. Everyone in VIKING II who consented to getting results and for whom there is genetic data, were informed in 2024. You can get in touch with VIKING Genes at viking@ed.ac.uk for more information.

How can I access a test or a risk assessment?

If a blood relative has been found to have the Whalsay BRCA2 gene variant, you can ask your GP to refer you to your local NHS genetics clinic to consider testing. Residents of the north of Scotland who have received a letter from a relative suggesting they have a test can contact the genetics teams directly following the instructions on the letter. Please note, GPs will not be able to directly assist with gene testing and any questions about this research.

Where can I find more information?

Practical and emotional cancer support and advice is available from CLAN. More information on BRCA2 and breast, ovarian, and prostate cancer in families is available via the NHS and MacMillan Cancer Support. If you want to see if you are eligible for a breast cancer risk assessment the Breast Cancer Now website has detailed information at https://breastcancernow.org/about-breast-cancer/awareness/breast-cancer-in-families/family-history-assessing-your-breast-cancer-risk/.

Information about cancer symptoms and how to reduce your chances of getting cancer is available from the NHS Inform website. People worried that they might have cancer should read the advice on NHS Inform and consult their GP.

 

Published: 06/06/2024 10:56