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Drug testing and analysis2026; doi: 10.1002/dta.70056

Gene Editing and the Future of Thoroughbred Breeding and Racing.

Abstract: Prohibited gene editing in horses (either in embryos or via cell culture and cloning) can result in both desired and undesired outcomes. If left undetected, changes can proliferate within the population in subsequent generations, posing a major threat to welfare and breed integrity.
Publication Date: 2026-03-11 PubMed ID: 41812645DOI: 10.1002/dta.70056Google Scholar: Lookup
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  • Journal Article

Summary

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Gene editing in thoroughbred horses involves modifying their genetic material to potentially enhance desirable traits, but unauthorized use of this technology risks unintended consequences that could harm horse welfare and the integrity of the breed.

Overview of Gene Editing in Thoroughbred Horses

  • Gene editing refers to the deliberate alteration of an organism’s DNA to achieve desired traits or eliminate undesirable ones.
  • In thoroughbred horses, this technology could be applied to improve racing performance, disease resistance, or other traits valued in breeding and racing.
  • The use of gene editing can occur at different stages, including editing embryos directly or through techniques involving cell culture and cloning.

Risks and Concerns Associated with Prohibited Gene Editing

  • Prohibited gene editing suggests unauthorized or unregulated interventions that may not be subject to oversight or ethical review.
  • Such interventions can lead to both intended (desired performance or health improvements) and unintended (off-target genetic changes) outcomes.
  • Undetected genetic modifications may propagate through breeding, becoming widespread in future generations without awareness or control.
  • This proliferation could potentially compromise the welfare of horses by introducing harmful mutations or unintended health issues.
  • It also raises significant concerns about maintaining the integrity of the thoroughbred breed, which relies on documented lineage and genetic consistency.

Implications for Welfare and Breed Integrity

  • Animal welfare is at risk if gene editing results in unforeseen health problems, reduced viability, or unintended physiological effects.
  • Preserving breed integrity is critical in the thoroughbred industry, where lineage and genetic purity are fundamental to racing standards and breeding practices.
  • The unregulated spread of edited genes could erode trust in the breed registry and undermine the sport’s credibility.
  • These issues highlight the need for stringent detection methods and regulatory frameworks to monitor and control gene editing applications in horses.

Conclusion and Future Considerations

  • The potential benefits of gene editing in thoroughbred breeding must be balanced against the ethical, welfare, and integrity risks posed by unauthorized use.
  • Effective surveillance and regulatory measures should be developed to detect gene editing interventions and prevent unintentional genetic changes from spreading.
  • Stakeholders in the racing and breeding industry should engage in dialogue to establish guidelines that ensure responsible use of gene editing technologies if they are to be implemented in the future.

Cite This Article

APA
Ryder E, Given J, Hamilton N. (2026). Gene Editing and the Future of Thoroughbred Breeding and Racing. Drug Test Anal. https://doi.org/10.1002/dta.70056

Publication

ISSN: 1942-7611
NlmUniqueID: 101483449
Country: England
Language: English

Researcher Affiliations

Ryder, Edward
  • LGC Ltd, Fordham, UK.
Given, James
  • British Horseracing Authority, London, UK.
Hamilton, Natasha
  • Equine Genetics Research Centre, Racing Australia, Scone, New South Wales, Australia.

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