The DNA test verifies the presence of the affected allele at PLOD1 locus responsible for WFFS, also known as Fragile Foal Syndrome (FFS)
- 30 to 40 - hair roots - envelope
- 5 mL - blood - K3 EDTA tube
- 2 to 5 working days
The genetic test verifies the presence of the affected allele at PLOD1 locus responsible for WFFS and the presents results as one of the following:
- N/ - Negative for WFFS. Absence of the affected allele at PLOD1 locus responsible for WFFS. Horses are clear for the FFS disease.
- N/WFFS - Positive heterozygous for WFFS. Presence of a mutated allele at the PLOD1 locus responsible for WFFS. Although unaffected by the disease, the horse is a carrier of WFFS and can pass the PLOD 1 allele to 50% of their progeny when bred.
- WFFS/ - Positive homozygous for WFFS. Presence of two mutated alleles at the PLOD1 locus responsible for WFFS. The foal is affected with the WFFS, the disease is present at the birth and affected foals show fragile, hyper-extensible and thin skin that results in open lesions and joint hyper-elasticity, and often foals need to be euthanised after birth due to the lethality of this genetic disorder.
Warmblood Fragile Foal Syndrome WFFS is an inherited autosomal recessive disorder caused by a single mutation in PLOD1 gene.
Clinical signs and affected breeds
The disease is present at the birth and affected foals skin lacks tensile strength (extreme skin fragility characterised by tearing, ulceration, etc. from contact with normal surroundings). Lesions occur anywhere on the body, but are most noted on pressure points and in addition to skin wounds, lesions are found on the gums and other oral cavity mucous membranes and the perineum. Limb joints are lax and hyper-extensible. Fetlocks are the most dramatically affected and affected foals cannot stand normally.
- WFFS/FFS is similar to Ehlers Danlos Syndrome (EDS) in humans.
- The FFS mutation has been reported in Warmblood breeds - 11 to 30% of WFFS carriers in Warmbloods (1,3,4), at low frequency in Thoroughbreds - 2,75% of Irish Thoroughbreds(2), and also at Hanoverian, Selle Français, KWPN, Oldenburg and Westphalians.
(1) Ablondi, M., Johnsson, M., Eriksson, S. et al. Performance of Swedish Warmblood fragile foal syndrome carriers and breeding prospects. Genet Sel Evol 54, 4 (2022). https://doi.org/10.1186/s12711-021-00693-4
(2)- Rowe, Á., Flanagan, S., Barry, G. et al. Warmblood fragile foal syndrome causative single nucleotide polymorphism frequency in horses in Ireland.Ir Vet J 74, 27 (2021). https://doi.org/10.1186/s13620-021-00206-1
(3) Dias, N. M., de Andrade, D., Teixeira-Neto, A. R., Trinque, C. M., Oliveira-Filho, J. P., Winand, N. J., Araújo, J. P., Jr, & Borges, A. S. (2019). Warmblood Fragile Foal Syndrome causative single nucleotide polymorphism frequency in Warmblood horses in Brazil. Veterinary journal (London, England : 1997), 248, 101–102. https://doi.org/10.1016/j.tvjl.2019.05.002
(4)Hoelzle, L., Stefaniuk-Szmukier, M., Długosz, B., Piórkowska, K., Ropka-Molik, K., Malvick, J., Penedo, M., & Bellone, R. R. (2020). Distribution of the Warmblood Fragile Foal Syndrome Type 1 Mutation (PLOD1 c.2032G>A) in Different Horse Breeds from Europe and the United States. Genes, 11(12), 1518. https://doi.org/10.3390/genes11121518