Molecular mechanism
Von Willebrand Disease (vWD) is an inherited bleeding disorder caused by deficiency or dysfunction of von Willebrand factor (vWF), a plasma glycoprotein essential for normal platelet adhesion and blood clotting (Boudreaux, 2012). Affected dogs may experience prolonged bleeding following injury or surgery, spontaneous bleeding from the nose or gums, bruising, or blood in the urine (Thomas, 1996). Three recognised forms of the disease exist, which differ in severity: Type I is characterised by reduced concentrations of normal vWF and typically causes mild to moderate bleeding, Type II results from qualitative defects in the vWF protein and is associated with moderate to severe bleeding, while Type III is characterised by an almost complete absence of vWF and is the most severe form of the disease.
The genetics and inheritance of von Willebrand Disease vary according to the disease type and breed. Type I is associated with the VWF c.7437G\u0026gt;A splice-site variant and shows autosomal dominant inheritance with incomplete penetrance in some breeds, including Doberman Pinschers and Kromfohrländers, while autosomal recessive inheritance has been proposed in others (Gentilini and Turba, 2013; Segert et al., 2019). As a result, the Type I genetic test identifies dogs carrying the risk variant but should be interpreted alongside clinical findings and additional haemostatic testing where appropriate (Segert et al., 2019). The appropriate genetic test should be selected according to both the breed and the form of von Willebrand Disease being investigated. If you are unsure then please send us an email.
References
NOTE: OMIA Type 1 -\u0026quot;Control:Use of DNA diagnostics as a sole diagnostic tool for vWDI is not advised as the c.7437A variant has been reported to be only partially associated with the disorder in the Doberman Pinscher breed and the Kromfohrländer breed (incomplete penetrance)\u0026quot;
References
Armas-Jimenez, A.C., Randolph, A., Clark, L.A., Evans, J.M., Brooks, M.B., Goggs, R. : A VWF missense variant in Havanese dogs with type 3 von Willebrand disease. Anim Genet 56:e70021, 2025. Pubmed reference: 40504041. DOI: 10.1111/age.70021.
Segert, J.H., Seidel, J.M., Wurzer, W.J., Geretschlaeger, A.M. : vWDI is inherited in an autosomal dominant manner with incomplete penetrance, in the Kromfohrländer breed. Canine Genet Epidemiol 6:3, 2019. Pubmed reference: 31131110. DOI: 10.1186/s40575-019-0073-4.
Vos-Loohuis, M., van Oost, B.A., Dangel, C., Langbein-Detsch, I., Leegwater, P.A. : A novel VWF variant associated with type 2 von Willebrand disease in German Wirehaired Pointers and German Shorthaired Pointers. Anim Genet 48:493-496, 2017. Pubmed reference: 28696025. DOI: 10.1111/age.12544.
Gentilini, F., Turba, M.E. : Two novel real-time PCR methods for genotyping the von Willebrand disease type I mutation in Doberman Pinscher dogs. Vet J 197:457-60, 2013. Pubmed reference: 23911791. DOI: 10.1016/j.tvjl.2013.02.023.
Boudreaux, M.K. : Inherited platelet disorders. J Vet Emerg Crit Care (San Antonio) 22:30-41, 2012. Pubmed reference: 22316339. DOI: 10.1111/j.1476-4431.2011.00702.x.
Kramer, JW., Venta, PJ., Klein, SR., Cao, Y., Schall, WD., Yuzbasiyan-Gurkan, V. : A von Willebrand\u0026#39;s factor genomic nucleotide variant and polymerase chain reaction diagnostic test associated with inheritable type-2 von Willebrand\u0026#39;s disease in a line of german shorthaired pointer dogs. Vet Pathol 41:221-8, 2004. Pubmed reference: 15133170. DOI: 10.1354/vp.41-3-221.
Venta, P.J., Li, J.P., Yuzbasiyan-Gurkan, V., Brewer, G.J., Schall, W.D. : Mutation causing von Willebrand\u0026#39;s disease in Scottish terriers Journal of Veterinary Internal Medicine 14:10-19, 2000. Pubmed reference: 10668811.
Rieger, M., Schwarz, H.P., Turecek, P.L., Dorner, F., Vanmourik, J.A., Mannhalter, C. : Identification of mutations in the canine von Willebrand factor gene associated with type III von-Willebrand-disease Thrombosis and Haemostasis 80:332-337, 1998. Pubmed reference: 9716162.
Thomas, J.S. :von Willebrand\u0026#39;s disease in the dog and cat. Vet Clin North Am Small Anim Pract 26:1089-110, 1996. Pubmed reference: 8863392. DOI: 10.1016/s0195-5616(96)50057-4.