FDA breakthrough designation reflects growing role of genome sequencing, says Mimi Lee, MD, PhD

The FDA’s Breakthrough Device Designation for GeneDx’s whole genome and exome tests underscores a broader shift in how genomic testing is being integrated into everyday clinical practice, particularly in pediatrics, according to Mimi Lee, MD, PhD. Rather than being reserved solely for genetics specialists, Lee said comprehensive sequencing is increasingly positioned as a diagnostic tool that can be ordered by general pediatricians and other frontline clinicians when standard evaluations fail to yield answers.

“I think, classically, certainly when I was trained in medicine, we referred patients to go see a genetics specialist,” Lee said. “But now we’re realizing that this is a tool that can be ubiquitously and universally used by physicians and physician teams…just like ordering a lab test or ordering a radiographic image.” She emphasized that any physician can order genomic testing to help identify objective genetic drivers of disease, particularly in children with unexplained or rare conditions.

The FDA designation, which applies to GeneDx’s ExomeDx and GenomeDx tests, is intended to expedite development and review of technologies that may offer more effective diagnosis of serious or life-threatening conditions. Lee noted that GeneDx’s decision to pursue FDA review was deliberate.

“The fact that we decided to go ahead and bring it to the FDA to have it approved as a medical test was a big thing,” she said. “And the fact that they responded by assigning it Breakthrough Device Designation was really exciting for us, and I think exciting for patients in the field.”

According to Lee, the designation signals growing regulatory recognition that genomic testing can meaningfully improve diagnostic precision. Exome sequencing evaluates protein-coding regions that account for about 2% of the genome, where many pathogenic variants are found, while whole genome sequencing captures structural and noncoding regions that may contribute to disease. “As we learn more—not just the exonic portions of the genome…but everything else around it, the other 98% of the genome—we are going to be able to address and target conditions much more precisely,” she said. “The more we do the sequencing, the more we learn about human biology,” she said. “It’ll be very, very rapid.” Over time, she expects this knowledge to support more individualized treatment strategies, whether through development of novel therapies or repurposing existing ones for specific genetic variants.

Importantly, Lee framed genomic testing as a way to strengthen—not replace—the role of general pediatricians.

“We will no longer have to treat every child like they are exactly the same as the next one with the same diagnosis,” she said. “This is going to help elevate the role of the general pediatrician…as just another tool to really hone in on what’s going on with this particular child versus the next one.”

Reference:

1. Ebert M. GeneDx receives FDA Breakthrough Device Designation for whole genome and exome tests. Contemporary Pediatrics. Published November 10, 2025. Accessed January 9, 2026. https://www.contemporarypediatrics.com/view/genedx-receives-fda-breakthrough-device-designation-for-whole-genome-and-exome-tests