Healthcare (Commonwealth Union) – Scientists from the University of Melbourne and the Murdoch Children’s Research Institute (MCRI) have created a groundbreaking blood test that can quickly identify rare genetic disorders in infants and young children. This innovation could eliminate the need for expensive and invasive diagnostic procedures, enabling families to access treatments much sooner.
While genome sequencing has improved the detection of rare conditions, it currently provides answers in only about 50% of cases. For the remaining patients, additional functional testing is required to determine whether a gene mutation is the underlying cause. These tests can be time-consuming—taking months or even years—and are often limited to diagnosing only a small number of specific disorders.
Now, according to new findings published in Genome Medicine, this newly developed blood test can identify abnormalities linked to around half of all known rare genetic diseases within just a few days. It does so by evaluating the disease-causing potential of thousands of gene mutations simultaneously—potentially replacing the need for thousands of individual functional tests.
Associate Professor David Stroud from the University of Melbourne pointed out that a condition is considered rare when it affects fewer than one in 2,000 people. There are over 7,000 such diseases, the majority of which are genetic in nature and many of which are severe and progressive.
“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 as it means those patients don’t have to undergo unnecessary and invasive testing such as muscle biopsies, which for a baby requires general anaesthetic and that doesn’t come without risks.”
Murdoch Children’s Research Institute Professor David Thorburn stated that offering a quick and accurate diagnosis gives patients a much better shot at survival, as it allows treatment to begin significantly earlier—if such treatments exist.
He further indicated that even when a child has tragically passed away due to an undiagnosed genetic condition, the new test can still be performed on preserved tissue to identify the mutation that caused the illness. This not only gives grieving families a sense of closure but also enables doctors to use the genetic information in IVF procedures to help parents conceive future children free from the same inherited disorder.
The research team compared their newly developed test with an existing clinically approved enzyme test currently provided by the Victorian Clinical Genetics Services at the Murdoch Children’s Research Institute (MCRI), which focuses on diagnosing mitochondrial disorders. These are serious and rare conditions that deprive the body’s cells of energy, leading to the failure or malfunction of one or more organs, and in some cases, can be fatal. The team discovered that, in comparison, their new test delivers superior diagnostic performance—it is significantly more sensitive and precise, and it yields results more quickly.
Dr Daniella Hock from the University of Melbourne indicated that a recent health economics study, carried out in partnership with the Melbourne School of Population and Global Health, demonstrated that their test could be made available at a similar price to the current enzyme test used for diagnosing mitochondrial diseases. She pointed out however, that theirs offers far better value, as it can screen for thousands of genetic conditions, while traditional functional tests are typically limited to identifying only a small set of disorders.
