Researchers at Weill Cornell Medicine-Qatar (WCM-Q) helped probe the genetic diversity and origins of the Arabian horse, prized all over the world for its beauty, grace and athletic endurance.

Renowned for its ability to thrive in extremely hot, arid environments, the Arabian horse is the oldest recorded breed of horse, with credible documentation stretching back more than 2000 years, placing its development in the Middle East.

WCM-Q Research on Arabian Horses 2
Breeders prize the Arabian horse for characteristics like heat tolerance and endurance, as well as its uniquely graceful appearance.

Working in collaboration with an international team of fellow researchers, scientists at WCM-Q helped conduct a comprehensive global sampling and analysis of the genomes of 378 individual Arabian horses in Qatar, Iran, UAE, Poland, USA, Egypt, Jordan, Kuwait, the United Kingdom, Australia, Denmark and Canada. Blood and hair samples were painstakingly collected from the horses over an eight-year period.

The international team of scientists was led by Samantha Brooks, a UF/IFAS Assistant Professor of Animal Sciences formerly based at Cornell University in Ithaca, New York and is now affiliated with the University of Florida.

The team of researchers from WCM-Q meanwhile, was led by Dr Joel Malek, Associate Professor of Genetic Medicine, who used the college’s state-of-the-art equipment and expertise to assist with the sequencing of the horse DNA.

The study was also made possible by the National Priorities Research Program (NPRP) grant 6-1303-4-023 from the Qatar National Research Fund, a member of Qatar Foundation. The paper, entitled ‘Genome Diversity and the Origin of the Arabian Horse’ has been published in Scientific Reports, a journal of the Nature series of publications.

According to Brooks the Arabian horse has a special mystique due to the long recorded history of the breed.

Arabian horse breeders, in particular, know their horse’s bloodlines many generations back. What we found was that in the area where this breed originates – likely the near East region, but we don’t know exactly – there’s a healthy level of diversity. This is particularly evident in populations from Bahrain and Syria, which suggests these are some pretty old populations.

The horse is prized for characteristics like heat tolerance and endurance, as well as its unique appearance, with a dish-shaped facial profile, wide-set eyes, an arched neck and a high tail carriage. It has been exported from its ancestral homeland for centuries, with some modern lineages drawn strictly from these smaller genetic pools, giving the breed a reputation for inbred disorders. While this was true for some groups they tested, Brooks noted that they also found remarkable diversity when considering the breed as a whole.

Brooks contrasted the discovery of more diverse populations with the samples they received from racing Arabians. According to another longstanding myth the Arabian contributed genetically to the modern Thoroughbred, but the racing Arabians’ DNA told a different story.

She said that what they found in the samples was not that much Arabian ancestry was part of the Thoroughbred line, but the opposite: that Thoroughbred DNA exists in most of the modern racing Arabian lines, indicating a more recent interbreeding within this group.

I can’t speculate on the how or why, but this is clearly the story the DNA is telling us.

Another implication of the study, Brooks said, is the potential to identify the genetic regions that determine some of the Arabian’s unique traits, like their facial profile. This could be expanded to identify the marker for other horse breeds’ head shapes, for example.

Dr Joel Malek said it was extremely gratifying to be part of the fascinating and interesting research about the iconic Arabian horse, which is so important to this region. He said that they are very proud to have been able to work with so many talented and dedicated researchers all over the world on the project, which underlines WCM-Q’s commitment to pursuing projects at the cutting edge of science that have great local significance, in line with the goals set out in Qatar National Vision 2020.

We are also very grateful for the support this project received from Qatar Foundation through Qatar National Research Fund, which made the research possible.

The study has a long list of co-authors, with contributors from the University of Tehran, Iran; University of Kentucky; University of Agriculture in Kraków, Poland; Hong Kong Jockey Club; Equine Veterinary Medical Center at Al Shaqab (a Qatar Foundation member); and the University of Veterinary Medicine Vienna, Austria. Elissa Cosgrove from Clark lab and Raheleh Sadeghi, a visiting scientist from Iran in the Antczak lab, shared first co-authorship of the study.

Dr Khaled Machaca, Professor of Physiology and Biophysics and Senior Associate Dean for Research, Innovations and Commercialization at WCM-Q said they are pleased that the advanced capabilities in genomic analysis they developed in the Biomedical Research Program at WCM-Q allow them to contribute to ground-breaking international projects such as this one.

The Arabian horse is truly a majestic creature and it is wonderful to be able to shed light on its genetic heritage in this way.

The study can be read in full throug this LINK.