The blood test has developed which could speed up the diagnosis of rare diseases in babies | Medical research

A new blood test that could help accelerate diagnostics for children born with rare genetic disorders has been developed by researchers in order to provide responses – and treatments – earlier.

Rare genetic disorders include a multitude of conditions, from cystic fibrosis to diseases relating to mitochondria – the powers of our cells. However, obtaining a diagnosis can be difficult.

“In most cases, people suspected of a rare disease undergo genomic tests, which have revolutionized their diagnosis, but generally leads to a diagnosis only about 50% of the time,” said Dr. David Stroud, co-author of the study of the University of Melbourne.

“Those who do not receive a diagnosis of genomic tests often undergo a long” diagnostic odyssey “of months when they undergo a myriad of other tests in an effort to interpret which of the many genetic changes detected in genomic tests cause the disease,” he added. “Some of these tests are very invasive, requiring for example muscle biopsies, which in children require a general aesthetic, which presents its own risks.”

Writing in the journal Genome Medicine, Stroud and his colleagues report how they sought to complete the genetic tests with another approach: to examine the myriad of proteins found in certain types of blood cells taken from a patient and compare them to those found in healthy people.

“Since genes are the instructions for making proteins, we then use this information to understand which thousands of changes in many different genes detected in a patient leads to a damaged protein and which are benign,” said Stroud.

The team claims that the approach means that the effects of many different genetic mutations can be analyzed at the same time and a yield is little than three days.

Among other results, the researchers have found that the new approach outperform golden tests in mitochondrial diseases which are used in parallel with genetic tests and have made the diagnosis of diseases where genomic tests alone had not been able to do so.

“Genomics is the first -line test and can resolve the diagnosis in around 30 to 50% of patients suspected of a rare disease. We believe that a single proteomic test can increase this diagnostic yield to 50 to 70% of suspicious patients, “said Professor David Thorburn, another research author of Melbourne University.

Although the study focuses on the use of the test for mitochondrial diseases, Stroud said that it was already applicable to about half of the 7,000 known rare diseases, although more work is necessary to demonstrate this.

Stroud added that for mitochondrial diseases as little as 1 ml of a newborn blood was necessary for the procedure, while current techniques involved muscle biopsy.

In addition, although a version focused on the mitochondria of the test has a cost similar to current techniques, it is not specific to a type of rare disease. This does not only make it more profitable, but, as Stroud noted, it also means that patients may avoid having to pass other unnecessary tests.

“This has obvious advantages for the patient and the health system,” he said.

A diagnosis does not only shed light on the disease and, in some cases, possible treatments. It also helps parents who plan to have other children by increasing the possibility of prenatal genetic tests.

Michal Minczuk, professor of mitochondrial genetics, at
The University of Cambridge, which was not involved in the study, praised research. “Overall, paper marks a very significant step in diagnostic practices by introducing a robust, fast and mini-invasive method to confirm and characterize genetic disorders,” he said. “This could considerably improve patient care by expanding the tools available for clinicians and researchers in genomic medicine.”

Robert Pitcehly, professor of clinical neurology and mitochondrial medicine at UCL Queen Square Institute of Neurology, agreed. “The next step is a wider validation and integrate this technology into the NHS diagnostic services to improve results for patients,” he said.