Multi-phase study led by UK’s Gluck Center reveals genetic diversity among Thoroughbred horses.
Thoroughbred horses have been an exceptional product of human selection for centuries, and the breed’s health and athleticism have enabled it to be used in the development of many modern horse breeds, if not to say most.
Purebred breeders have long been interested in maintaining genetic diversity and have been very wise in selecting against genetic determinants that negatively affect health and fertility . At the same time, some worry that purebred breeds have become lacking in diversity.
To shed more light on this topic, a research team led by the University of Kentucky’s Gluck Horse Research Center recently completed the first phase of a study that offers the most comprehensive analysis yet. on the genetics of the American mixed breed to date. Previous studies of purebred diversity were based on sampling small subsets of the genome. This study by Ernie Bailey, PhD, Ted Kalbfleisch, PhD, both from the Gluck Center and Jessica Petersen, PhD, from the University of Nebraska-Lincoln, is based on sequencing the whole genome of Thoroughbred horses. .
The goal of the study was to create a database that catalogs the genomic variation of today’s Thoroughbred horses and to generate anonymized (by horse) data that will form the basis of knowledge. method for use in tracking changes in genetic diversity over time.
According to Bailey, the completion of their first phase of research in 2021 shows that Thoroughbred horse diversity matches that of other domestic animals and is within range for other horse breeds.
During this period, 1,000 thoroughbred samples were collected from horses in Kentucky, California, Florida and New York. The horses were examined and 120 were selected for whole-genome sequencing in order to capture as much genetic variation of the population as possible. As a result of sequencing these horses, a catalog of 15 million DNA variants among American crossbreeds is being generated. This catalog can be used to track future changes in Thoroughbred populations as well as to build computer models to assess how changes in livestock practices might affect genetic structure of the population.
The second phase of ongoing research will be a sequencing project that will help protect the breed from harmful recessive genes. The occurrence of variants will be identified and programs will be used to predict whether those variations could have a potential negative effect on a gene. Additionally, the team is interested in using part of a whole-breed survey to know the overall frequency of genes.
Bailey said. “If we wait until 1% of the population develops a recessive harmful disease, then 18% of all Purebred people will be carriers. This approach allows us to detect genes like so before they become popular.”
Importantly, these data will be made publicly available so that researchers at other institutions can perform studies on specific traits or genes. The genetic data, and the approach used to create them, also represent a new tool available to breeders to use to maximize the genetic potential of each foal and ensure good health. The behavior of the Horse resembles an elite population of equine athletes.
If you want to learn more about this project, please contact Bailey ([email protected]). If you are interested in supporting this project through financial donations, please contact Danielle Jostes ([email protected]).
