A gene mutation in gaited horses identified by Swedish researchers is advantageous for harness-racing horses, and the findings may ultimately have a major impact on future horse breeding.
In domestic horses, it has had a major impact on their diversification, as the altered gait characteristics of several breeds apparently require the mutation, according to the researchers.
Gus Cothran, a professor in the Animal Genetic Lab at Texas A&M University, was part of a team of researchers that examined motion in horses and mice.
Cothran and the team used a process called “whole genome SNP analysis” to study the genes of 70 Icelandic horses that had either four gaits or five, with the pace being the fifth gait. This pointed to a gene identified as DMRT3 that is critical for horse motion and limb movement.
” ‘Gaitedness’ is a trait that naturally occurs in all horses, but many breeds have been developed for a specific speed or gait,” Cothran explains.
The team sequenced the DMRT3 gene of the test horses and found that in almost every case of gaited horses, there was mutation in the DMRT3 that caused a premature “stop codon” which causes the protein product of the gene to be terminated before the whole protein is completed. This alters the function of the protein which leads to the differences associated with the gait.
Cothran and the team also examined the same gene and its effect on mice.
“We specifically looked at the gene and its effect on the movement of mice, such as its swimming ability,” he adds.
“The motion ability of mice seemed suppressed and was similar, though not identical to that of gaited horses.”
Cothran says with more research, the findings could have critical importance to horse breeding and horse racing. Many horses are specifically bred for certain types of gait, such as harness racing.
“We need to examine the DMRT3 on certain breeds and see if it can directly affect the speed and movement of horses,” he adds.
“Naturally, it’s something that horse breeders and anyone involved with horse racing would be interested in and would want to know about. These findings could have a major impact on future horse breeding.
“We think it’s an exciting step in looking at motion, speed and limb movement, and it’s possible it could have implications in other species, too.”
The project was funded by grants from the Swedish Brain Foundation and computer resources were supplied by the Royal Swedish Academy of Sciences Research.