Odds on the FAST Gene
- M.H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, Kentucky 40546 USA
This extract was created in the absence of an abstract.
Racehorse genetics has not been a traditional topic considered in research laboratories; however, the development of molecular tools could provide new opportunities. Cold Spring Harbor Laboratory’s Banbury Center hosted a conference March 8–11, 1998, entitled “Horse Genomics and the Genetics of Factors Affecting Horse Performance.” Participants included scientists studying the genetics of the horse, horsemen, veterinarians, and scientists working in related fields with other species. The central questions for the conference were (1) How can we best investigate the genetic factors that influence racehorse performance? and (2) Has the Thoroughbred horse breeder exhausted the genetic potential within the breed to produce faster racehorses?
Genetic Diversity
Thoroughbred racehorses include some of the most valuable animals in the world. The world record sale price was set in 1985 when an untested yearling colt, named Seattle Dancer, sold at auction in Lexington, Kentucky, for the record price of $13.1 million. Clearly, this untrained, untried yearling commanded this record sale price based on its pedigree and the perception among horsemen that genetics is important. The Thoroughbred pedigree dates back to the late 1600s and may be the oldest recorded pedigree (Weatherby 1791) for any animal population. As a consequence of three centuries of selection, Thoroughbred racehorses are the fastest horses in the world over distances of 1–1.75 miles.
The Thoroughbred racehorse is descended from a group of English-bred horses, including stallions and mares, imported from North Africa and the Middle East as well locally available English mares (Willet 1981). According to pedigree records, the foundation stock numbered only 80 horses, with 21 contributing 80% of the pedigree for modern Thoroughbred horses (Fig. 1; Cunningham 1991). However, this estimate ignores additional mares introduced to the population when the Thoroughbred developed into an international breed and Thoroughbred stallions from England were crossed with non-Thoroughbred mares in …
