PSSM2 tests at IAFH
Healthy, powerful horses are the goal of all breeders. The International Association of Future Horse Breeding, IAFH for short, supports you in achieving this goal. The horse breeding organizations working together under the umbrella of the IAFH - currently these are the Oldenburg Associations, the Trakehner and Holsteiner Verbands as well as the Westphalian Horse Stud Book - have made it their mission to make information from genetic analyzes for modern, successful breeding planning comprehensively accessible to their members . They see transparency and support in the classification and use of available information as core tasks.
The range of services offered by the IAFH also includes tests for hereditary diseases such as PSSM2. The abbreviation PSSM stands for polysaccharide storage myopathy, i.e. a muscle disease that is associated with excessive storage of sugar in the muscles. This description also applies to PSSM1, but not to PMMS2. Because under PSSM2 various muscle diseases are summarized, the cause of which is not the mutation that causes excessive sugar storage. The disorders in muscle metabolism or defects in the muscle structure, which impair muscle function, are based on different genetics. The often unspecific symptoms include unclear lameness as well as muscle dents, hardened and tense muscle parts, muscle breakdown and ataxia, but also the so-called "training intolerance", which means that the affected horses are not willing to perform and often appear weak after a comparatively short training period. The disease is usually diagnosed in horses aged seven to ten years, but symptoms can also appear in younger horses, although these are then often (even) weaker.
Variants of different genes are causally associated with PSSM2. However, symptoms do not always appear in carriers; there are certainly horses among them that are very successful in sport. Great importance is attached to feeding and management, although many questions remain unanswered. The presence of PSSM2 gene variants does not necessarily mean that the animal that has tested positive is not suitable for breeding. However, it can make sense to mate the carrier with a horse that has tested negative.
“Meanwhile, we IAFH shareholders are able to offer tests for PSSM2 for the horses of our members via the new laboratory analysis. And at conditions that make it easier to provide more information and transparency on this hotly debated topic," says Dr. André Hahn, the deputy breeding director of the Oldenburg Associations, who is very familiar with the main areas of work at the IAFH. “And breeders will soon be able to order tests themselves via their online breeder account. Our IAFH co-partner, the vit data center in Verden, then carries out the corresponding genome data analyses.” Until then, the associations offer the service of receiving inquiries from their members and forwarding them to vit to initiate the analysis. The procedure is simple: For horses that have already been SNP-genotyped - since the start of the 2021 season, all newly registered horses within the IAFH have been routinely examined for parentage verification with the SNP markers - no additional sample material and no further laboratory analysis are required. For the examination of all other horses, it is sufficient to send in hair samples, whereupon the SNP genotyping takes place in the laboratory and then the PSSM2 markers are read out by vit. The life number of the horse and the membership number of the customer at the respective association must be given. The net price for the SNP genotyping, which is a prerequisite for reading out the markers, is 20 euros, the actual PSSM2 test costs 160 euros net.
