Identification of sample donor by 24-plex short tandem repeat in a post-race equine plasma containing dexamethasone.
Abstract: Animal sport such as horseracing is tainted with drug abuse as are human sports. Treatment of racehorses on race day with therapeutic medications in most cases is banned, and thus, it is essential to monitor the illicit use of drugs in the racing horse to maintain integrity of racing, ensure fair competition and protect the health, safety and welfare of the horse, jockeys and drivers. In the event of a dispute over the identity of the sample donor, if the regulator can provide evidence that the DNA genotype profile of the post-race sample matched that of the alleged donor, then the potential drug violation case might be easily resolved without legal challenges. Methods: We present a case study of a racehorse sample that tested positive for dexamethasone in a post-race plasma sample in Pennsylvania (PA) but the result was challenged by the trainer of the horse. Dexamethasone is a synthetic glucocorticoid widely used in the management of musculoskeletal problems in horses but its presence in the horse during competition is banned by the PA Racing Commissions. The presence of dexamethasone in the post-competition plasma sample was confirmed using liquid chromatography-tandem mass spectrometry. However, this finding was challenged by the trainer of the horse alleging that the post-race sample was not collected from his/her horse and thus petitioned the Commission to be absolved of any wrong-doing. To resolve the dispute, a DNA test was ordered by the PA Racing Commission to identify the correct donor of the dexamethasone positive sample. For this purpose, a 24-plex short tandem repeat analysis to detect 21 equine markers and three human markers was employed. The results indicated that all the samples tested had identical DNA profiles and thus, it was concluded that the samples were collected from the same horse and that the probability of drawing a false conclusion was approximately zero (1.5 × 10(-15)). Conclusions: The plasma sample confirmed for the presence of dexamethasone was collected from the alleged horse.
Publication Date: 2014-02-17 PubMed ID: 24600547PubMed Central: PMC3935034DOI: 10.1186/2193-1801-3-94Google Scholar: Lookup
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- Journal Article
Summary
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The research discusses a case in which a racehorse tested positive for a banned substance during a race in Pennsylvania. The trainer disputed the test result, but DNA analysis confirmed that the sample did indeed come from the accused horse.
Objective
This study encompasses a case of a racehorse testing positive for dexamethasone, a banned substance in Pennsylvania horse races. When the finding was disputed by the horse’s trainer, the researchers used a 24-plex short tandem repeat analysis to confirm that the positive sample did, in fact, come from the accused horse.
Background
- The integrity of horse racing is paramount, involving not just the welfare of the horse, but also the fairness of competition and safety of the jockeys and drivers. To this end, monitoring drug use in racehorses is vital.
- Therapeutic medications are typically banned on race days. In the case discussed in this study, the horse tested positive for dexamethasone—a synthetic glucocorticoid forbidden by the Pennsylvania Racing Commissions. This substance, often used in the management of musculoskeletal problems in horses, is not allowed during any competitive race in Pennsylvania.
Methods and Results
- The researchers used liquid chromatography-tandem mass spectrometry to confirm the presence of dexamethasone in a post-race plasma sample taken from the horse.
- When the horse’s trainer disputed the finding, claiming that the sample could not have come from his horse, the Pennsylvania Racing Commission ordered a DNA test. They used a 24-plex short tandem repeat analysis, capable of detecting 21 equine markers and three human markers.
- The results of this DNA analysis were crucial. All samples tested exhibited identical DNA profiles, leading to the conclusion that they were all collected from the same horse. Moreover, the probability of obtaining these results due to chance alone was shown to be virtually zero, at approximately 1.5 x 10(-15).
Conclusions
- The researchers concluded that the plasma sample testing positive for dexamethasone indeed came from the horse in question, thereby confirming its illicit drug use and corroborating the original test results.
Cite This Article
APA
Chen JW, Uboh CE, Soma LR, You Y, Jiang Z, Li X, Guan F, Liu Y.
(2014).
Identification of sample donor by 24-plex short tandem repeat in a post-race equine plasma containing dexamethasone.
Springerplus, 3, 94.
https://doi.org/10.1186/2193-1801-3-94 Publication
Researcher Affiliations
- University of Pennsylvania School of Veterinary Medicine, New Bolton Center Campus, 382 West Street Road, Kennett Square, PA 19348 USA.
- University of Pennsylvania School of Veterinary Medicine, New Bolton Center Campus, 382 West Street Road, Kennett Square, PA 19348 USA ; Pennsylvania Equine Toxicology & Research Center, Department of Chemistry, West Chester University, 220 E Rosedale Avenue, West Chester, PA 19382 USA.
- University of Pennsylvania School of Veterinary Medicine, New Bolton Center Campus, 382 West Street Road, Kennett Square, PA 19348 USA.
- University of Pennsylvania School of Veterinary Medicine, New Bolton Center Campus, 382 West Street Road, Kennett Square, PA 19348 USA.
- University of Pennsylvania School of Veterinary Medicine, New Bolton Center Campus, 382 West Street Road, Kennett Square, PA 19348 USA.
- University of Pennsylvania School of Veterinary Medicine, New Bolton Center Campus, 382 West Street Road, Kennett Square, PA 19348 USA.
- University of Pennsylvania School of Veterinary Medicine, New Bolton Center Campus, 382 West Street Road, Kennett Square, PA 19348 USA.
- University of Pennsylvania School of Veterinary Medicine, New Bolton Center Campus, 382 West Street Road, Kennett Square, PA 19348 USA.
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