One in a hundred people with Orkney heritage have a gene mutation that increases the risk of breast and ovarian cancer, according to a study.
Researchers spotted the gene variant repeatedly in women from the archipelago off the north-eastern coast of Scotland who had the cancers, and clinical genealogy showed that patients with the variant had family roots tracing back to the island of Westray.
It is believed to be the first time such a geographic ancestral link has been established within the UK.
Researchers also discovered the specific Orkney gene variant in smaller numbers in genetic testing across the UK and in the US.
The gene mutation is likely to have come from a founder individual who lived at least 250 years ago, the paper published in the European Journal of Human Genetics said.
The findings by geneticists from the universities of Aberdeen and Edinburgh were outlined to residents of Westray on Thursday evening, with those present told that scientists had linked a variant in the gene BRCA1 to the island.
Prof Zosia Miedzybrodzka, director of the NHS North of Scotland Genetic Service, said: “Developing cancer is not solely down to carrying the BRCA1 variant alone.
“There are many complex factors, and some people with gene alterations will not get cancer.
“However, we know that testing and the right follow-up can save lives.”
Previous research has found that women from certain ethnic backgrounds, such as Ashkenazi Jews, have a high rate of a specific BRCA gene variant.
Planning is under way for a trial scheme, organised by NHS Grampian and funded by the cancer charity Friends of Anchor, which will offer testing for the gene variant to anyone living on the island with a Westray-born grandparent, regardless of a family history of the diseases.
If the pilot is successful, the long-term aim is to offer a test to everyone in Scotland with a Westray-born grandparent.
Miedzybrodzka said because it was hereditary, the gene variant could affect multiple members of families.
She added: “Risk-reducing surgery, breast screening with MRI from age 30, and lifestyle advice can all improve health for women with the gene.
“Men do not need to take any particular action for themselves, but they can pass the gene on to female descendants.”
Everyone has the BRCA genes, but not everyone has mutations in them.
The actor Angelina Jolie underwent a double mastectomy in 2013 after discovering that she carried a faulty copy of the BRCA1, leading to the greater awareness of the gene defect.
Jolie, 47, lost her mother to ovarian cancer and carrying the faulty gene put her at a high risk of developing both forms of the disease.
About one in 1,000 women across the UK have a BRCA1 variant, giving them a high lifetime chance of developing breast cancer and ovarian cancer, but most of these cancers happen due to chance damage to genes.
More than 2,000 volunteers took part in the research and gave genetic data to the Orkney Complex Disease Study, known as Orcades.
The NHS advises that risk-reducing surgery is not the only option and recommends awareness of any changes to breasts, annual screenings and MRI scans to help detect the form of cancer, while lifestyle changes such as healthy eating and exercise can “sometimes reduce risk”.
There is currently no reliable screening test for ovarian cancer, it added.
