Thousands of people with Jewish ancestry are to be offered a genetic test owing to their higher risk of some cancers.
NHS England is rolling out a national BRCA gene testing programme to pick up changes that push up cancer risk, with anyone over 18 with Jewish ancestry offered a simple saliva test.
Saliva samples are collected by people in their own homes and then sent to a lab for testing.
Anyone with at least one Jewish grandparent can register for a saliva kit to be sent to their home address by visiting: https://jewishbrca.org/.
Inherited changes in BRCA1 or BRCA2 genes mean people have a significantly higher risk of developing some cancers.
Estimates suggest that a fault in one of the BRCA genes affects around one in every 400 people, but people with Jewish ancestry are over six times more likely to carry the faults.
Data shows 55% to 72% of women who inherit a harmful BRCA1 variant and 45% to 69% of women who inherit a faulty BRCA2 variant will develop breast cancer by old age.
Those with a faulty BRCA1 gene also have a 39% to 44% risk of developing ovarian cancer and the risk is 11% to 17% for those with a harmful BRCA2 variant.
Changes in BRCA also push up the risk of developing pancreatic cancer and prostate cancer.
Research published in 2022 by the University of Cambridge found that men who carry a BRCA2 mutation have a 27% risk of developing prostate cancer by the time they are 80, more than double the rate compared to non-carriers.
Meanwhile, carrying a defective copy of either BRCA1 or BRCA2 more than doubles a person's risk of pancreatic cancer to 2.5-3% by age 80, the study found.
The new programme from NHS England aims to identify thousands more people carrying faults in the BRCA genes over the next two years.
This means they can access regular scans to check for tumour growth and can access treatment more quickly if they do have cancer.
NHS England said its pilot of the programme has already seen thousands of people come forward for testing. It expects to test around 30,000 people over the next two years.
Peter Johnson, national clinical director for cancer at NHS England, said the programme had the potential to save lives.
He added: "We know it can be daunting finding out whether or not you have an altered BRCA gene, and some people may feel they'd rather not know, but finding out early means people can get the support they need from the NHS.
"We want as many people as possible to take advantage of this testing programme, so please do come forward for a simple saliva test if you are eligible - most people won't have an altered gene, but if you do, the NHS can provide you with further testing, surveillance or treatment as early as possible."
Charities Jnetics and Chai Cancer Care have been running awareness campaigns to encourage people to get tested.
Nicole Gordon, Jnetics chief executive, said: "We are delighted to see the NHS Jewish BRCA Testing Programme officially launch.
"The initial pilot phase has proven to be a huge success and we are now able to roll this out more broadly and offer the Jewish community a huge opportunity to gain the knowledge that will help mitigate against the impact of hereditary cancer and ultimately save lives."
Lisa Steele, chief executive at Chai, added: "We want to ensure that this programme reaches as many people as possible.
"For more than 30 years, Chai Cancer Care has been supporting members of the Jewish community affected by a cancer diagnosis.
"This is a landmark moment as we can now harness developments in genetic screening to increase the chances of preventing the onset of cancer.
"Chai is dedicated to ensuring that anyone who needs support at any point during this process can access that help."
