Blood test breakthrough
A breakthrough blood test developed by researchers at the University of Melbourne and Murdoch Children’s Research Institute (MCRI) is set to bring new hope to parents of babies and children with rare genetic diseases, offering faster and less invasive diagnoses.
The new test, detailed in the journal Genome Medicine, is capable of detecting abnormalities linked to up to 50 percent of all known rare genetic diseases within days. It works by analysing the pathogenicity of thousands of gene mutations simultaneously – potentially replacing the need for thousands of existing functional tests that can take months or even years to complete.
While genome sequencing has transformed the way rare diseases are diagnosed, it only succeeds in providing answers in about half of all cases. For the remaining families, the path to a diagnosis can be long and uncertain, often involving invasive procedures like muscle biopsies – sometimes requiring general anaesthetic in babies.
Associate Professor David Stroud from the University of Melbourne explained the potential of the new test: “If our blood test can provide clinical diagnoses for even half of the 50 percent of patients who don’t get a diagnosis through genome sequencing, that’s a significant outcome. It means those patients don’t have to undergo unnecessary and invasive testing.”
There are over 7,000 rare diseases – defined as those affecting fewer than 1 in 2,000 people – many of which are serious, progressive, and genetic in origin.
Professor David Thorburn from MCRI highlighted the emotional and medical impact of getting a faster diagnosis.
“By providing patients and their families with a rapid clinical diagnosis, the patient has a greater chance at survival as they can begin treatment far sooner, if available,” he said. “Even in cases where a child has died from an undiagnosed genetic disease, this new test can be carried out on tissue samples to determine the mutation responsible. This can bring closure for families and inform future IVF decisions to help them have children who haven’t inherited the disease.”
The research team tested the new method against a currently used enzyme test for mitochondrial diseases – rare disorders that severely affect cellular energy, leading to organ failure and, in some cases, death. They found the new test to be more sensitive, more accurate, and much faster.
Dr Daniella Hock from the University of Melbourne said the new test also stacks up economically.
“A recent health economics analysis showed that our test could be offered at a similar cost to the enzyme test currently used for mitochondrial diseases but is far more cost-effective because it screens for thousands of genetic diseases instead of just a few.”
Backed by a $3 million grant from the Australian Government’s Medical Research Future Fund, the team is now recruiting 300 patients with a range of geneticconditions to further study the test’s broader impact.
In time, it’s expected the test will become a diagnostic service offered by the Victorian Clinical Genetic Services – opening the door to earlier answers, better outcomes, and renewed hope for families navigating the uncertainties of rare disease.
