Innovative Blood Test Accelerates Diagnosis of Rare Genetic Diseases in Children

Researchers from the University of Melbourne and Murdoch Children's Research Institute (MCRI) have developed a groundbreaking blood test that enables rapid diagnosis of rare genetic diseases in infants and children. This new method significantly reduces the need for invasive and costly procedures, offering families quicker access to essential treatments.

While genome sequencing has traditionally been used to diagnose rare diseases, it successfully identifies the cause in only about half of cases. The remaining patients often require additional functional tests to confirm gene mutations, a process that can take months or even years, with no certainty of conclusive results. Many of these tests are limited to specific disorders, further complicating diagnosis.

The newly developed blood test, published in the journal Genome Medicine, can detect abnormalities in up to 50% of known rare genetic diseases within a matter of days. It works by analyzing thousands of gene mutations simultaneously to assess their pathogenicity, potentially replacing multiple traditional functional tests.

Associate Professor David Stroud of the University of Melbourne explained, "There are over 7,000 rare diseases, most of which are genetic and serious. Our blood test has the potential to significantly impact diagnosis and treatment by providing faster results. If it can diagnose even half of the cases that currently go undetected with genome sequencing, it would spare patients from invasive procedures like muscle biopsies, which pose risks, especially to infants."

Murdoch Children's Research Institute's Professor David Thorburn highlighted the importance of early diagnosis. "Rapid and accurate diagnosis allows for timely treatment, improving survival chances. It also helps families find closure in cases where a child's condition is fatal and can inform future reproductive decisions, including IVF options to avoid inheriting genetic diseases."

The research team compared their test's effectiveness with an existing enzyme test used for diagnosing mitochondrial diseases, which cause energy production failures in cells. The new blood test proved more sensitive and faster, demonstrating its potential as a superior diagnostic tool. Cost-wise, it is comparable to current enzyme testing but offers broader application, testing for thousands of disorders instead of just a few.

Currently, the team is recruiting 300 patients with various genetic conditions to further evaluate the test's utility. It is expected that this innovative diagnostic method will soon be available through the Victorian Clinical Genetic Services, revolutionizing how rare genetic diseases are diagnosed in children.

For more information, the study by Daniella H. Hock et al., titled "Untargeted proteomics enables ultra-rapid variant prioritization in mitochondrial and other rare diseases," is accessible in Genome Medicine [DOI: 10.1186/s13073-025-01467-z].