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Control of gene doping in human and horse sports

Gene Therapy volume 29, pages 107–112 (2022)Cite this article

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Gene doping can take different forms which pose varying risks and ethical considerations in human and equine competition. Whilst both species are likely to be targeted for gene doping with inserted transgenes, the application of gene editing will almost certainly differ between the two. In humans, gene editing is most likely to be performed on adults, and as such will not affect the germline. This contrasts with the situation in horses which could be gene edited as adults or prenatally, as zygotes or embryos. In fact, editing horses as early as possible in development is appealing to reduce mosaicism and increase the efficiency of the edit [1]. The editing of racehorse embryos to create genetically modified animals would be a direct contravention of Stud Book and horseracing rules. With the recent publication of a method to gene edit horse embryos [2], this is a particular concern for Horseracing Authorities. Further, in human sports, the recipient of gene doping can consent to the doping treatment, while clearly horses cannot, adding a further dimension to the ethical problem of gene doping in animals.

The most important component of doping control is doping detection tests. Several methods to detect the various types of gene doping have been and are being developed, based on quantitative polymerase chain reaction (qPCR), digital PCR and more recently, next-generation sequencing (NGS) [3,4,5,6,7]. This article describes the advantages and disadvantages of the currently available and under development detection methods to detect gene doping.

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Fig. 1: Gene doping regulations in human and horse sports.

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Author notes

  1. These authors contributed equally: Teruaki Tozaki, Natasha A. Hamilton

Authors and Affiliations

  1. Genetic Analysis Department, Laboratory of Racing Chemistry, Tochigi, 320-0851, Japan

    Teruaki Tozaki

  2. Equine Genetics Research Centre, Racing Australia, Flemington, NSW, 2337, Australia

    Natasha A. Hamilton

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  1. Teruaki Tozaki
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Correspondence to Teruaki Tozaki.

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Tozaki, T., Hamilton, N.A. Control of gene doping in human and horse sports. Gene Ther 29, 107–112 (2022). https://doi.org/10.1038/s41434-021-00267-5

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