skip to Main Content
+49 7071 565 44 850 Facebook

Connective tissue disorder leading to the death of the foal.


  • 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.

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).

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.

Test information: This test detects a mutation in the PLOD1 gene. This test is performed by partner laboratory.

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.

Further information is available at Online Mendelian Inheritance in Animals.

Breeds affected:

Test #: H123

Samples: Blood, Hair

Price: 39 € (net)

Time required: 10 - 14 days

Back To Top