Children’s Mercy Announces Single-Test Genetic Disease Diagnosis

Children’s Mercy researchers have demonstrated that a test that can improve the speed and accuracy of diagnosing rare genetic conditions in children. FILE PHOTO.

Posted September 24, 2025

Children’s Mercy researchers have found a breakthrough that can improve the speed and accuracy of diagnosing genetic conditions in children.

Children’s Mercy announced on Monday that it has developed a single, advanced long-read sequencing (LRS) test in a study that was published in the Journal of the American Medical Association Pediatrics.

Children’s Mercy was the first to use 5-base HiFi LRS, a genomic sequencing system, in the clinical setting to accelerate diagnosis for even more patients and families.

“Children’s Mercy is a trailblazer in every sense of the word—we’re not just advancing medicine, we’re reshaping it,” President and CEO of Children’s Mercy, Dr. Ale Quiroga, said in a release. “This research isn’t simply a breakthrough; it’s a blueprint for what pediatric care can and should be. By deepening diagnostic precision and elevating the care experience for families, we’re equipping our clinicians with sharper tools, faster answers and greater insight. And we’re doing it for the children who need us most.”

In the study, researchers compared 235 children who received the new LRS test to more than 500 children who underwent traditional genetic testing.

The study found:

  • Higher diagnostic success: LRS identified the cause of a child’s condition significantly more often than standard testing, increasing the diagnostic rate by 10% over all previous tests combined.
  • Faster answers: On average, families received a diagnosis in less than a month, compared to the traditional methods, which took about 91 days on average.
  • Fewer tests, less stress: LRS often replaced the need for multiple rounds of testing, reducing the emotional and financial burden on families.

“As we continue to explore the noncoding regions of the genome and expand access to this technology, we’re opening doors to diagnoses that were once out of reach,” Director of Translational Genomics at Children’s Mercy, Dr. Isabelle Thiffault, said in the release. “This is how we change the future of pediatric medicine—by building a foundation for discoveries that will help generations of children to come.”

Children’s Mercy hopes to use the initial study as a foundation for expanded testing and further understanding of noncoding regions. Children’s Mercy has used LRS in its Genomic Answers for Kids (GA4K) program, a first-of-its-kind pediatric data repository to facilitate the search for answers and novel treatments for pediatric genetic conditions. In just four years, GA4K has delivered more than 2,100 diagnoses.