Doctors from Radbod University and Maastricht University in the Netherlands have developed a test that allows them to better study genetic information and make more accurate diagnoses, according to the results of a study published in the American New England Journal of Medicine. The development, according to scientists, significantly exceeds standard diagnostic methods.
The basis for the development was the method of long genome sequencing, a technology that allows you to read significantly longer DNA fragments compared to standard methods. It helps analyze complex areas, identify large structural rearrangements, repeated sequences, and more accurately determine the boundaries of mutations.
Standard tests measure fragments of the genome that contain biological information that are only up to 300 nucleotides long. The new test reads up to 20,000, expanding diagnostic capabilities.
“In 832 patients with a rare genetic disease, final diagnosis was made in 160 patients (19.2%) using long-read genome sequencing and 137 patients (16.5%) using standard medical testing,” the study noted.
Despite the slight increase in diagnostic efficiency in percentage terms, the development is significant because it concerns atypical diseases. The new test reads not only the constituent parts of the genome, but also modifications on the outside of DNA that can “turn genes on and off” and are sometimes the cause of rare diseases, study co-author and genome bioinformatics specialist Christian Gillissen told Medical Xpress.
The researchers compared current standard diagnostics, which often involve multiple tests to make a diagnosis, with a new DNA test in 1,000 patients. A year after its introduction into clinical practice at a Dutch hospital, the method showed a wider diagnostic range, notes translational genomics specialist Lisenka Vissers.
“We have shown that the new test allows us to make 3% more diagnoses. It can also replace 15 other tests. We recommend using this test throughout the world as the main one,” the scientist emphasized.
According to genomics technology professor Alexander Heuschen, who was also involved in the study, the number of diagnosed cases will continue to rise in the future as he and his team established links between genetic abnormalities and various diseases.
“I think this will become the new standard for genomic diagnostics and the only test we will do in the future,” Hoischen said.
