skip to Main Content
+49 7071 565 44 850 Facebook

(Warmblood) Fragile Foal Syndrome (WFFS)


→ Connective tissue disorder leading to the death of the foal.

Instructions for ordering:

  1. Enter the information of the first horse for which you want to order the test
  2. Add to cart
  3. Go to cart to check out, or
  4. Enter the information for a second horse
  5. For sample collection follow the instructions here.
  6. You can use this template to send in hair samples.
  7. Please also send the completed order form together with the samples.

For a breeder or veterinarian discount please contact us before ordering.

Any information you include here is optional, but will be included on the certificate of results (except “Additional Info”).

Enter the name of your animal
Enter your animal's date/year of birth
Enter the breed name
Enter the registration number if known
Enter the microchip number
Is there anything else you would like to tell us about your horse? Reason for testing, symptoms etc.?

General information

  • Connective tissue disease in warmbloods and related breeds that leads to skin detachment.
  • Mutation in the PLOD1 gene. This encodes the PLOD1 protein, which supports the collagen fibres so that they can fold and connect → Essential for the structural integrity of the body: skin, membrane, joints.
  • Affected animals must always be humanely euthanized with hours.
  • Similar to human connective tissue disease “Ehlers-Danlos syndrome” (type IV), also caused by a mutation in the PLOD1 gene (LH1)
  • Hypothesis: Most (W)FFS pregnancies end in spontaneous abortions.
  • Starting in January 2019, all stallions active in breeding in Germany must be tested and the results have to be made public (registration regulations stallion book I / II according to ZVO).


  • Majority of foals are not carried to term – most are spontaneously aborted or stillborn
  • Newborn foals have skin detachment from the body without external influence
  • Separation of skin and subcutis without bleeding.
  • Foal makes no or only weak attempts to get up.
  • Hypermobile joints.

Inheritance and Genotypes

Inheritance: autosomal recessive

→ Only animals with two copies of the variant (ffs/ffs) are affected. Animals with only one copy (N/ffs) are clinically normal carriers.

Possible Genotypes:

Genotype: The horse is:
N/N normal. The horse has no copies of the mutations causative for (Warmblood) Fragile Foal Syndrome and therefore cannot pass it on to its offspring.
N/ffs a carrier. The horse is a clinically normal carrier. The variant will be passed on to its offspring with a probability of 50%.
ffs/ffs affected. The horse does not survive more than a few hours.



  • Carriers may be bred to normal animals (N/ffs x N/N) without any risk of producing affected offspring. The offspring should also be tested before breeding to determine if they are carriers or normal.
  • Breeding two carriers (N/ffs x N/ffs) is not recommended due to the possibility of 25% of the offspring being affected.
  • Affected animals (ffs/ffs) usually die within a few hours.


Monthoux, C., de Brot, S., Jackson, M., Bleul, U., Walter, J.: Skin malformations in a neonatal foal tested homozygous positive for Warmblood Fragile Foal Syndrome. BMC Vet Res 11:12, 2015. Pubmed reference: 25637337. DOI: 10.1186/s12917-015-0318-8.

Back To Top