Test Detail

Bleeding disorder caused by a qualitative defect of von Willebrand factor, with abnormal multimers and moderate to severe severity. In the German Pointer it is associated with variants in the VWF gene. Complementary, not substitutive, test to the clinical examination.

Documented in German Wirehaired Pointer and German Shorthaired Pointer; also described in Boykin Spaniel, Chinese Crested and German Spitz. Limited prevalence data.

- Mucosal bleeding (epistaxis, gingival bleeding, digestive or urinary bleeding)
- Bruising and prolonged bleeding after surgery or trauma
- Variable clinical severity
- Not all laboratory abnormalities are accompanied by clinical signs

Kramer et al. (2004) described a variant in the VWF gene and a PCR test in a line of German Shorthaired Pointer. Vos-Loohuis et al. (2017) identified in the German Wirehaired Pointer the variant c.1657T>G as the main candidate, which also segregates in the shorthaired one.

- Genotype breeding animals
- Avoid mating animals carrying the variant involved in the breed
- PCR testing allowed the variant to be eliminated from affected lines (Kramer 2004)
- Consult the veterinarian before making breeding decisions

Type 2 presents with abnormal vWF multimers; the blood count and coagulation tests guide, but definitive diagnosis requires genotyping. The c.4937G variant also appears in the Chinese Crested without clinical signs, which requires cautious interpretation according to breed.

1. Vos-Loohuis M et al. 2017, A novel VWF variant associated with type 2 von Willebrand disease in German Wirehaired Pointers and German Shorthaired Pointers. Anim Genet. PMID: 28696025. 2. Kramer JW et al. 2004, A von Willebrand's factor genomic nucleotide variant and polymerase chain reaction diagnostic test associated with inheritable type-2 von Willebrand's disease in a line of German Shorthaired Pointer dogs. Vet Pathol. PMID: 15133170. OMIA:001339-9615.