Seven years ago a number of breeders' groups showed interest in the genetic analysis of the autochthonous breeds of horse from the Basque Country. Thus, at the Department of Genetics, Physical Anthropology and Animal Physiology of the University of the Basque Country (EHU-UPV), sheep, cows and horses native to Euskal Herria were studied. The aim of this livestock study was to find out the state of conservation of these breeds and also to identify the animals. What is more, thanks to the work of the farmhouses, these native breeds have conserved much of their original characteristics.
In the case of horses, four breeds were studied: the pottokas, the Basque mountain pony, the Jaca Navarra and the Burguete breed. Three genetic markers were used for the analysis.
Paternity and variability
First the genetic variability of these livestock breeds was analysed to see if the native animals had sufficient variability in the face of possible diseases. To this end, microsatellites were selected - regions of DNA with specific features - as primary markers.
Microsatellites moreover, are highly useful for identification. With these, the equivalent of a fingerprint can be compiled for each horse; that is to say, they can be used to identify both the mother and the father with 90 % accuracy.
417 animals were analysed in all: 147 pottokas, 163 Basque mountain ponies, 62 Jacas Navarras and 45 of the Burguete horse breed. Two of these breeds are heavy or given over to meat production (Jaca Navarra and Burguete); on the other hand, the other two are considered to be lightweight breeds.
According to the results, the two breeds for meat production are crossed with foreign breeds in order to increase their size and weight; particularly, stallions from outside have been used. So, one can observe a gradient between the autochthonous breeds: the pottoka has had the least external influence and the Burguete breed the most.
Also, comparing breeds native to the Basque Country with others, it was observed that the former have a greater genetic variability in terms of their microsatellites. This has an explanation: native breeds usually run wild in the mountains and so, a mare may be mounted by more than one stallion.
Morphology and genes
Subsequently the researchers selected as a second marker a SNP (single nucleotide polymorphism) of a gene related to the morphology of animals. Given that the four breeds are morphologically different, they wished to see if this difference existed genetically as well. The results showed that an SNP variant hardly appeared in the pottokas; on the other hand, the greater the influence of outside breeds, the more this variant appeared. According to the data, in this case also, it is the pottoka that has had the least external influence.
The last marker analysed was mitochondrial DNA - solely from the mother. With mitochondrial DNA the phylogenetic relations between the four native breeds can be defined. Moreover, the relations with other breeds in the world and their origin can be known.
The results show that the four native breeds are related to each other; above all there are geographical relations: the pottoka with the Basque mountain pony and the Jaca Navarra with the Burguete. Moreover, it has been observed that there are relations with other breeds in Europe and the rest of the world. But there still exist many gaps to fill in order to establish the phylogenetic relations of the European breeds.
There is also the significant data that a variant of the SNP has only been found here and in England.
Thus, these studies have thrown up some interesting and indicative data but it would appear that, in concrete, in the Iberian Peninsula there still remains important data to be discovered about the domestication of the horse in Europe.
Department: Genetics, Physical Anthropology and Animal Physiology
Faculty: Science and Technology (University of the Basque Country, Leioa)
Image: The Provincial Council for Alava