Further research into the equine speed gene “C” has revealed a surprising conclusion, although I think it’s been misreported by the Irish Telegraph, which boldly claims that
Dr Hill’s study showed that the speed gene entered bloodlines when the Darley Arabian, the Godolphin Arabian and the Byerley Turk were bred with native British horses, mainly Shetlands, but also the now-extinct Galloway.
What I suspect this really means is that the riding/hunting British mares that were bred to the founding fathers of the thoroughbred breed were of Shetland descent – one cannot imagine the wealthy aristocratic owners of those expensive imported horses putting them to Shetlands (who really were not considered such gems in those days) and expecting racehorses. The research does sound fascinating.
Dr Hill, based at the Equinome company in UCD she founded with Derby-winning trainer Jim Bolger, genetically tested almost 600 horses, 40 donkeys and two zebras to trace speed gene C-type myostatin. The experiment also looked at pedigree lines and included 22 Eurasian and North American breeds, museum bone and tooth specimens from 12 legendary stallions born between 1764 and 1930 and 330 elite performing racehorses across three continents.
“We wanted to understand where speed in the thoroughbred came from,” Dr Hill said. …
They also attribute wider expansion in bloodlines to Nearctic’s son Northern Dancer (1961-1990), regarded as one of the most influential stallions of modern times. [blogger’s note: does this mean that Northern Dancer had more Sheltie blood? Otherwise he didn’t really cause wider expansion in bloodlines, more like the opposite]
The study showed how a thoroughbred’s genetic make-up has developed from the focus on stamina to sprinting as racing developed. In the 17th century prized thoroughbreds were raced lightly, did not take to tracks until age five or six and ran repeatedly head-to-head over two to four miles until one horse had two victories or distanced the opponent. In the last 100 years, an increased premium has been put on speed and precocity with more two-year-old races. Dr Hill added: “For example, in Australia, the myostatin speed gene type (C:C), which is best suited to fast, short-distance, sprint races, is more common and there is a market-driven demand for horses with at least one copy of the C type gene variant.”
UPDATE: Thanks to my brother for passing on this take on the report by Lab Spaces, which seems to be more accurate:
Scientists have traced the origin of the ‘speed gene’ in Thoroughbred racehorses back to a single British mare that lived in the United Kingdom around 300 years ago, according to findings published in the scientific journal Nature Communications. … “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.”
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. …
The study identified the Shetland breed as having the highest frequency of the C type gene variant. The Shetland represents local British horse types, which were the preeminent racing horses prior to the formal foundation of the Thoroughbred.”