A NEW genetic test to identify Traditional Irish Horses has been developed in response to concerns over the dilution of the Irish Sport Horse gene pool by European warmblood horses.

The research behind the test was published this week in the peer-reviewed Journal of Genetic Resources in a paper entitled ‘The genetic composition of the Traditional Irish Horse – towards the development of a DNA-ancestry test for the preservation of traditionally bred Irish Sport Horses’.

Demand has developed among breeders to identify traditionally bred Irish Sport Horses, referred to as the Traditional Irish Horse (TIH), and to establish conservation measures for the lineages descended from the original Irish hunter.

A dramatic change in the breed profile of the Irish Sport Horse population in recent years has led to a growing concern that the traditional traits of the Irish Sport Horse are being displaced by a pan-European sport horse. In 2014, the percentage of foals registered in the Irish Sport Horse Studbook by foreign-bred sires was 37.5% from just 1.1% in 1990.

In 2020, of the 48 stallions approved by Horse Sport Ireland that have at least five Irish Sport Horse progeny at least 10 years of age, only eight were TIH, with 65% being European warmbloods.

Kevin Noone, Chairman of the Traditional Irish Horse Association (TIHA) said: “There is a real possibility that the TIH will die by neglect, and we will lose our invaluable Irish equine genetic heritage. The recent Burghley five-star event, when there were three TIH placed in the top 10, and the continuing presence of Cruising, Clover Hill and King of Diamonds in many of the dam lines of our leading show jumpers, emphasises what we are in danger of losing.”

Since 2017, TIH foals have been identified in the Irish Sport Horse Studbook by having Traditional Irish Horse Category ISH (TIH) referenced on their passports. This assignment of TIH status is dependent on animals having complete pedigree data to confirm their heritage. However, for some animals, complete pedigrees are not available, and despite a breeder’s knowledge of their ancestry they cannot be officially identified as a TIH.

Noone added: “Being able to accurately assess the genes of horses when some of their breeding is unknown would be a powerful breeding tool.”

DNA test

To develop the DNA test for TIH, scientists from the Irish equine science company Plusvital collaborated with Horse Sport Ireland and the TIHA. They used modern SNP technologies to evaluate the ancestral genetic contributions to different cohorts of the Irish Sport Horse that were defined on the basis of pedigree. The research determined the maximal ancestry component of warmblood genetics required to assign TIH status with a high degree of accuracy, which is the basis for the new test.

Commenting on the research findings, lead scientist on the project Emmeline Hill, Professor in Equine Genomics at University College Dublin and Chief Science Officer at Plusvital, said: “Current efforts to assign TIH status to traditionally bred horses are hindered by the fact that many Irish Sport Horses may have an unregistered dam or sire in their pedigree.

“Genetic ancestry testing has immediate practical applications to identify TIH, particularly in the absence of complete pedigree information. Our results show that Irish Sport Horses with less than 15% warmblood genetics measured in their DNA can be accurately assigned as TIH.”

Professor Hill continued: “This new DNA test provides a novel route for conservation efforts and the promotion of the Irish horse in equestrian sport. Now that Irish Sport Horse registration requires a SNP based parentage test, the information gained from that test could also be used to identify horses that qualify on the basis of genetics as TIH.”

Kevin Noone added: “It is vital that we work with geneticists at the leading edge of breeding research and unlock more of the mysteries regarding inheritance and herd improvement. Acceptance of a genetic test to assign TIH status to a horse would be a prize of immense value to all our breeders.”

The TIHA aims to gain broader recognition of the importance of Traditional Irish bloodlines in Irish Sport Horse breeding and in the equestrian marketplace. The TIHA is performing an additional research project to screen horses using the new DNA-based test. Anyone interested in getting involved in the project should contact the TIHA. The results of that project are expected in the coming months.