Gene Doping and the U of A Scientists Building the Test to Catch It

Elite sports may soon face a form of cheating that requires new detection approaches. Instead of taking a banned substance that clears the body within days, athletes might alter their own DNA with a single injection, rewriting genes that govern muscle growth or how the body uses oxygen.

The change could be permanent and, with today's testing methods, almost invisible.

That scenario, known as gene doping, is still science fiction. No athlete has done it effectively, according to experts, and the health risks are severe, potentially fatal. But two technologies have matured to the point that anti-doping officials no longer treat it as far-fetched.

First, viruses engineered to carry genes into muscle now reach it roughly 10 times more efficiently than they could in 2019. Second, CRISPR gene editing has made precise genetic changes routine in the laboratory.

As part of its annual open call for scientific research proposals, the World Anti-Doping Agency (WADA) funded the U of A's research project "Systemic Biomarkers of Skeletal Muscle Gene Doping Using Third Generation Sequencing."

WADA supports scientific research aimed at advancing anti-doping science and developing new and improved methods to detect prohibited substances and methods. The agency awarded a two-year, $250,000 grant to a U of A team developing a blood test that could detect gene doping no matter which editing tool an athlete used.

The project also points to a broader strength at the U of A, where federally funded labs are using gene editing to attack the genetic roots of disease. That research puts the university on the front lines of a field racing to turn CRISPR into medicine.

A portable long-read DNA sequencing device in the lab of Christopher Nelson, associate professor of biomedical engineering. The technology reads long, continuous stretches of DNA, allowing researchers to identify engineered genetic sequences that do not occur in nature. (Photo by Reid Williams)

The test itself is the work of Christopher Nelson, an associate professor of biomedical engineering whose lab develops gene-editing therapies for muscular dystrophy and other diseases. Nelson trained at Duke University on some of the earliest CRISPR treatments aimed at Duchenne muscular dystrophy, and his lab houses the long-read DNA sequencing technology at the center of the project.

"It's currently science fiction. There's no example of someone doing gene doping in any kind of effective way," Nelson said.

The concern is that the tools are "ready enough" that someone might risk it for even a small competitive edge, he added.

Nelson's test looks for genetic fingerprints left behind in the bloodstream. When a gene carrier, like an engineered virus, is used for gene editing in muscle, traces of that engineered material leak back into the blood, where long-read sequencing can detect them. The test searches for combinations that do not occur in nature, such as a viral sequence fused to a human muscle gene.

Because it targets those signatures rather than a specific editing method, it aims to catch gene doping whether an athlete used gene transfer, CRISPR or a newer tool and to do so from a routine blood draw rather than a muscle biopsy.

Kevin Murach (Photo by University Relations)

But the project is as much about muscle as it is about DNA, and that half belongs to Kevin Murach. A muscle physiologist who built his research program at the U of A before joining the University of Missouri this summer, Murach first carried the anti-doping agency's concern back to Fayetteville and helped design the study around it.

His work answers an important question identified during WADA's grant evaluation process: whether hard training makes gene doping easier or harder to detect. To find out, Murach adapted an exercise model he developed for laboratory mice, a progressively weighted wheel-running regimen that trains the animals much the way an athlete trains. The team can then learn whether real exertion sharpens the signal in the blood or buries it.

"The people this protects are the athletes who train honestly and still have to line up against someone who might not. Getting a test ready before gene doping becomes real is worth doing," Murach said.

The two worked together for years on muscle gene-editing projects funded by the National Institutes of Health and the Department of Defense, and Murach's move did not end the collaboration. He remains a full partner on the research and will return to campus for the experimental work, the first round of which begins this fall.

"Chris [Nelson] knows how to find the fingerprints. I know how muscle behaves when you push it. Neither half catches a gene doper alone, which is why this had to be a partnership," Murach said.

Nelson does not oversell the threat. The risks of self-administered gene therapy, from immune reactions to organ damage, far outweigh the slim gains an athlete might see today. But another leap in delivery technology could change that math, he said, which is why WADA wants a test ready in advance.

For Nelson, the project mirrors his day-to-day research, which uses the same tools to heal rather than to cheat.

"What can we do to fix genetic disease?" he said. "What can we do to make people live longer and healthier?"

About the College of Engineering:  The University of Arkansas College of Engineering is the state's largest engineering school, offering graduate and undergraduate degrees, online studies and interdisciplinary programs. It enrolls more than 4,700 students and employs more than 150 faculty and researchers along with nearly 200 staff members. Its research enterprise generated $47 million in new research awards in Fiscal Year 2025. The college's strategic plan, Vision 2035, seeks to build the premier STEM workforce in accordance with three key objectives: Initiating lifelong student success, generating transformational and relevant knowledge, and becoming the destination of choice among educators, students, staff, industry, alumni and the community. As part of this, the college is increasing graduates and research productivity to expand its footprint as an entrepreneurial engineering platform serving Arkansas and the world. The college embraces its pivotal role in driving economic growth, fueling innovation and educating the next generation of engineers, computer scientists and data scientists to address current and future societal challenges.