A Monash University study is investigating the feasibility of population-wide DNA testing of young people to screen for high risk BRCA genes and genetic variants for gastrointestinal cancers and familial hypercholesterolemia.
The government-funded DNA Screen study led by Associate Professor Paul Lacaze, Head of Public Health Genomics at Monash will offer saliva DNA tests to 10,000 people aged 18-40 across Australia.
The study investigators says it is the world’s first preventive genetic screening study designed specifically to assess population DNA screening through a national healthcare system.
Associate Professor Lacaze says he hopes the project will enable a more efficient and equitable approach to genetic testing, identifying far more people at high risk than current testing model in which publicly-funded testing via Medicare is only only available to a small number of people who meet restrictive criteria.
“Providing genetic testing based on family history alone is not enough. Up to 90% of those at high risk in the general population are not identified by current family history-based testing. Most people don’t find out about their genetic risk until it’s too late, like after an incurable cancer or heart attack is diagnosed. We want to change that,” he said.
“We hope to identify those at risk while they are young and healthy, not after the fact, and empower them to make more informed decisions about their health,” he added. “For some people, this could save their lives through early detection and prevention of cancer and heart disease. This will also save considerable health system costs in Australia through prevention.”
DNA Screen will identify people with DNA variants in the BRCA1 and BRCA2 genes that lead to an increased risk of hereditary breast and ovarian cancer in women, and also to breast and prostate cancer in men, although not as strongly. The DNA Screen test will also focus on Lynch Syndrome, which increases risk for colorectal, endometrial and other gastrointestinal cancers.
Those found to be at high risk after DNA testing – about one in 75 or 1.3% – will have their situation explained by experts and be offered genetic counselling and prevention measures, such as regular scans and check-ups.
The study investigators say people found to have the high risk genes can be offered proven interventions available to reduce risk if identified early. These include medications, attending annual check-ups and screens from age 30, and the option of risk-reducing surgery for some people.
The DNA test also encompasses heart disease risk, focusing on familial hypercholesterolemia (FH) or ‘genetic high cholesterol’, which results in high risk of heart disease from a young age. Despite effective medications such as statins being available to reduce risk, an estimated 95% of FH carriers are currently undiagnosed.
DNA Screen is recruiting young people via social media, offering a free test to anyone in Australia aged 18-40, which involves placing a saliva sample into a small tube received by mail, and sending it back in a postage paid envelope. People can sign up online at dnascreen.monash.edu
The eventual goal is to develop a new population-based DNA screening program that could be offered through the Australian public healthcare system, available to everyone but targeted on certain medically-actionable conditions where early detection is key.
“We aim to [develop] an evidence base for the public acceptability, scalability and cost effectiveness of a national criteria-free DNA Screening program, similar to Breastscreen or the National Bowel Cancer Screening Program,” they say.
DNA Screen genomics lead Dr Tu Nguyen-Dumont said the project was well placed to change the thinking and implementation of genetic testing in healthcare.
“The combined expertise from world-class collaborators and state-of-the-art biobanking and genomics facilities at Monash University will ensure the success of this study,” she said.