A new test developed by researchers at the University of Pennsylvania School of Veterinary Medicine (Penn Vet) can detect the presence of gene doping in equines. Partly supported by the Pennsylvania Horse Breeders Association (PHBA) and the Pennsylvania State Horse Racing Commission, the findings, which systemically detect the local administration of illicit, gene doping therapies, are a significant breakthrough. Unlike other small molecule pharmaceuticals, gene doping agents trigger cells to produce performance-enhancing proteins, which often are virtually indistinguishable from naturally occurring proteins within the body, making it more difficult to determine whether or not an animal has had gene therapy.
The team of Penn Vet researchers has created and validated a quantitative real-time polymerase chain reaction (PCR) test–a term that has become common vernacular due to COVID-19 tests-which is able to detect the presence of a gene doping agent in plasma and synovial fluid after its intra-articular administration in horses.
“For the first time, we have demonstrated that a PCR test performed on a blood sample can detect the local administration of a gene therapy into the joint of a horse,” said Mary Robinson, PhD, VMD, DACVCP, assistant professor of Veterinary Pharmacology and director of the Equine Pharmacology Laboratory at Penn Vet's New Bolton Center. “While this test is currently limited in that it can only detect a specific gene therapy, it provides proof of concept that a gene therapy administered into the joint can be detected in a blood sample in a manner that is quick, convenient, and consistent with our long-term goal of deploying pre-race testing someday in the future.”
The researchers at Penn Vet were able to detect the gene doping agent in equine joint fluid after it was administered intra-articularly and in blood for up to 28 days, making it useful for both pre-race and out-of-competition testing.
More work is being done by Penn Vet with the goal of someday creating “biological passports” and screening tests that would successfully identify multiple gene doping agents for even longer periods of time. Researchers believe biomarkers could also be key in detecting gene doping as well as predicting injuries before they happen.
“We still have a lot of work to do to better understand the nature of biomarkers and how to fully harness their capabilities, but the science for detecting gene doping is getting there and much more quickly than any of us could have anticipated when we started this research,” said Robinson. “Ideas that once may have seemed unattainable–like a hand-held, stall-side testing device–are now coming into sight as real and tangible possibilities. We just need continued support to help get us there.”