Below is a quoted passage from an article from theHorse. It explains new knowledge about Genes and the gaited horse.

"...Gaited horses rely on the 'gait-keeper mutation,' DMRT3_SER301STOP, to maintain their gaiting at high speed without breaking into a canter. Horses with this mutation tend to use intermediate (i.e., trotting or pacing) gaits more frequently, says Brooks.

'Racing performance and gait are much more complex than can be explained by a single gene, but this gene has a major impact on gait,' says Bailey.

In a 2014 evaluation of breeds worldwide, Swedish researchers found this mutation in 68 of 141 breeds. It was most common among gaited breeds or harness racing horses and often absent in other breeds. Bailey says selection for it has enabled its spread in Standardbreds, Saddlebreds, Missouri Fox Trotters, Paso Finos, Icelandic horses, and Kentucky Mountain Saddle horses, to name a few. ..." Horse Hints Horse Breeds Index (400+ Breeds)

For More Information:

Genetic Problems in Horses
Horse Genetics
Coat Colors Pinto and Paint
Horse Color Information (Genetics)
Horse Color Breeding Charts
Horse Colors and Markings
Genome Sequence, Comparative Analysis, and Population Genetics of the Domestic Horse and About Equine DNA Roadmap
How Your Horse Got His Color (And Why You Should Care)
Horse Color Information (Genetics)
Horse Colors and Markings
Genome Sequence, Comparative Analysis, and Population Genetics of the Domestic Horse
Horse Color Breeding Charts
Genetic Problems in Horses
Molecular Tests for Coat Colours in Horses
Pinto or Paint?
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