A study earlier this year found one in 100 people with grandparents from the islands off the north-eastern coast of Scotland, has a mutation of the gene BRCA1.

Across the UK, it is around one in 1,000 women who have the BRCA1 gene.

It is likely the gene variant came from one of the founding members of Westray - an Orkney island which has a population of under 600 people - at least 250 years ago, according to the research.

The gene mutation was repeatedly spotted in women from Orkney who have the cancers, most of whom could also trace their family ancestry back to the small island of Westray.

In a small trial on Westray, organised by the local NHS trust and funded by the island's development trust, anyone living in Westray with a Westray-born grandparent will be offered a test for the variant.

Assisted by Professor Jim Wilson from the University of Edinburgh, the research was led by Zosia Miedzybrodzka, professor of medical genetics at the University of Aberdeen and director of the NHS North of Scotland Genetic Service.

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Prof Miedzybrodzka said: "The NHS Grampian genetics clinic and lab teams are delighted to offer this pioneering new service to Westray residents which will improve care and save lives.

"I am grateful to every single person that has made this pilot happen. We are setting up a system that will hopefully extend to the rest of Orkney and Scotland as soon as funding allows."

Residents on Westray can pick up a testing kit from their GP or from the Westray Development Trust office.

Tests will only be available to those on the island, those who know of a direct family connection to the BRCA1 gene or have a significant history of the cancers in their family.

They will then be processed in Aberdeen, and anyone found to have the variant will be be offered access to counselling, specialist care and support and testing for relatives.

If successful, the pilot will be rolled out to test everyone in Scotland with a Westray-born grandparent.

Awareness of the faulty gene was raised when Hollywood actress Angelina Jolie underwent a double mastectomy a decade ago, after losing her mother to ovarian cancer and then discovering she had a BRCA1 variant.

The NHS recommends talking to your GP if cancer runs in the family, or if you are worried about your own risk. They may refer you for a genetics test, which will tell you if you have inherited one of the cancer risk genes.