‘Speed gene’ in modern racehorses traced to Brit mare from 300 years ago

Washington -  The origin of the ‘speed gene’ in Thoroughbred racehorses has been traced back to a single British mare that lived in the United Kingdom around 300 years ago.

Scientists were able to reveal the origin of the ‘speed gene’ (C type myostatin gene variant) by analysing DNA from hundreds of horses, including DNA extracted from the skeletal remains of  12 celebrated Thoroughbred stallions born between 1764 and 1930.

“Changes in racing since the foundation of the Thoroughbred have shaped the distribution of ‘speed gene’ types over time and in different racing regions,” explained Dr Emmeline Hill, the  senior author of the study, and a genomics scientist at the School of Agriculture and Food Science, University College Dublin.

“But we have been able to identify that the original ‘speed gene’ variant entered the Thoroughbred from a single founder, which was most likely a British mare about 300 years ago, when  local British horse types were the preeminent racing horses, prior to the formal foundation of the Thoroughbred racehorse,” she stated.

The international scientific team led by scientists from University College Dublin (UCD), Equinome Ltd., and the University of Cambridge, have traced all modern variants of the original  ‘speed gene’ to the legendary Nearctic (1954-1973), and attribute the wider expansion of these variants to Northern Dancer (1961-1990), the son of Nearctic, and one of the most influential  stallions of modern times.

“Having first identified the ‘speed gene’ in 2010, we decided to see if we could trace the origin of the gene variant using population genetics coupled with pedigree analysis. We wanted to  understand where speed in the Thoroughbred came from,” explained Dr Hill.

“We traced the economically valuable gene variant by determining ‘speed gene’ type in almost 600 horses from 22 Eurasian and North American horse breeds, museum bone and tooth  specimens from 12 legendary Thoroughbred stallions, 330 elite performing modern Thoroughbreds from 3 continents, 40 donkeys and two zebras,” she added.

The findings were published in the scientific journal Nature Communications.