Researchers in Sweden and the United States have identified the gene responsible for producing ambling gaits in horses. The single gene, called DMRT3, seems to affect the nerve cells critical for the control of gaits in horses.
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Single gene has major impact on gaits in horses and in mice
One gait-keeper gene allows horses to move in unusual ways | Not Exactly Rocket Science | Discover Magazine
Mutations in DMRT3 affect locomotion in horses and spinal circuit function in mice : Nature : Nature Publishing Group