People skip a life-saving test for one big reason. In a month, that reason will be gone

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What happens when evidence alone isn’t enough?

That was the problem faced by public health researcher Dr Jane Tiller a decade ago when she realised DNA screening could be catching and preventing thousands of cancers and early heart attacks each year.

There was a major barrier in the way, however – people were scared that life insurers would weaponise their results to deny them coverage or jack up premiums.

In exactly a month, a law will come into place banning life insurers from doing just that.

Tiller spent more than a decade fighting for the reform, which throws open the door for larger-scale studies on “preventative genomics” to help identify the 90 per cent of people carrying high-risk genes who are currently undetected.

Tiller was awarded the Eureka Prize for Emerging Leader in Science, Technology and Engineering last week for her campaign to change the law.

“I’d love to say that I’m most excited about the prize, but I have to say that I’m more excited about the reform that’s coming in,” says Tiller, an associate professor from the School of Public Health and Preventive Medicine at Monash University.

Her vision is for a publicly funded national DNA screening program.

Tiller and colleagues from the DNA Screen research project applied for $50 million in the latest federal budget to test 100,000 people for three genetic conditions, in a trial that could lead to a national program. They were rejected.

So what conditions can we catch early, how has this research already saved lives, and why is it so hard to get politicians excited about prevention?

Ten thousand tubes of spit

For research published in Nature Health in January, Tiller and her colleague Professor Paul Lacaze ran a DNA screening pilot study targeting thousands of young Australians.

The researchers offered to test people aged between 18 and 40 for 10 genes linked to three conditions.

They screened for hereditary breast and ovarian cancer through the well-known BRCA genes, which in some cases can increase cancer risk by more than 70 per cent.

They also looked for Lynch syndrome, which boosts the risk of bowel and endometrial cancer due to faulty DNA repair genes. One in 280 Australians may carry the gene deficiency, according to the Cancer Council, but only 5 per cent of cases have been identified.

Third, they tested for familial hypercholesterolaemia, a genetic condition that results in abnormally high levels of “bad” LDL cholesterol from birth and can lead to early heart disease (half of all men with the disorder have heart attack or stroke by age 50, and half of women by 60).

“These three conditions are considered internationally to be ready for population screening because they are very high-risk and they are preventable,” Tiller says.

Tiller and her colleagues aimed to recruit 10,000 people. Within a day, 30,000 had applied.

Of the eventual 10,263 who spat into a tube for genetic testing, 202 had high-risk genes underscoring one of these conditions. Most people with high-risk genes said none of their immediate blood relatives had the associated disease.

The majority of participants with the high-risk genes accepted risk management and were able to take action. Some lost weight and cut down alcohol. Many organised annual MRIs under direction from their doctors.

One participant from Perth with a BRCA variant went for an MRI when she turned 30. She rang Tiller over Christmas to say she had breast cancer.

“She had no symptoms, it wasn’t visible on ultrasound,” Tiller said.

“The likelihood that that would have been detected at a late stage is very, very high if she hadn’t been part of our program, and the outcomes for someone with stage 3 or 4 cancer are very different to the outcomes for someone with stage 1 or 2.”

Is it cost-effective?

A study led by Tiller’s colleague Lacaze in The Lancet’s eClinicalMedicine attempted to predict what would happen if the tests were rolled out widely.

Modelling assumed that free DNA tests were offered to all Australians aged 18 to 40, and half of those people took it up (about 4 million).

“I am a bit unusual – there aren’t a lot of scientists walking around Parliament House.”

Dr Jane Tiller

The results estimated the testing would prevent 4047 deaths, 2612 cancers (1140 breast, 950 ovarian, 451 colorectal and 71 endometrial) and 542 cases of non-fatal heart disease.

Testing so many people would cost $832 million, assuming each test cost $200.

The authors considered the “incremental cost-effectiveness ratio” of each “quality-adjusted life-year” gained through the DNA screening program which, in public health-speak, is a way of assessing how much an intervention saves the health system.

A cost of $50,000 per quality-adjusted life year is considered the benchmark in terms of how much a health intervention saves. The DNA screening would come in at $23,926, which the authors concluded is a cost-effective result.

When science gets political

So if the screening has proved popular and cost-effective, why have efforts to expand preventative DNA screening stalled?

“The challenge, really, is that this is squarely in the prevention context,” Tiller says.

“Obviously, governments and the health ministers have to consider a range of priorities, and often they are acute, and often they are immediate.

“Prevention is very hard to get funded from a political point of view … we don’t step outside and think, ‘I’m so glad that I am not in hospital dying of cancer today!’ Prevention is very invisible when it’s done well.”

That makes it difficult to advocate for prevention. But advocacy is something Tiller has mastered alongside research – and she says more scientists should take their expertise to the halls of power.

It was only five years ago she went to her local MP, Josh Burns, and got the political ball rolling to stop life insurers discriminating against people based on their genetic risk results.

“I am a bit unusual – there aren’t a lot of scientists walking around Parliament House,” she says. “But I think it should be more common.

“Research is important, but if no one’s actually reading your research, if it’s not influencing policy, it’s hard to see what the point of that is.”

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