von Willebrand's Disease, type 1

von Willebrand's Disease (vWD) type 1 is a clotting disorder that usually causes mild bleeding tendencies in affected dogs though some may have more severe signs. The low level of von Willebrand's factor impacts the bloods clotting ability.

Found in

1 in 73 dogs

in our testing

Key Signs

Bleeding following surgery or trauma

Age of Onset

At birth

Present at birth


Autosomal Recessive

For autosomal recessive disorders, dogs with two copies of the variant are at risk of developing the condition. Dogs with one copy of the variant are considered carriers and are usually not at risk of developing the disorder. However, carriers of some complex variants grouped in this category may be associated with a low risk of developing the disorder. Individuals with one or two copies may pass the disorder-associated variant to their puppies if bred.

Likelihood of the Condition

High likelihood

At risk dogs are highly likely to show signs of this disease in their lifetime.

What to Do

Here’s how to care for a dog with vWD type 1

Partner with your veterinarian to make a plan regarding your dog’s well-being, including any insights provided through genetic testing. If your pet is at risk or is showing signs of this disorder, then the first step is to speak with your veterinarian.

For Veterinarians

Here’s what a vet needs to know about vWD type 1

Type 1 von Willebrand’s disease is the mildest form of vWD and while many dogs may be subclinical, some dogs may exhibit more severe clinical signs. Excessive bleeding may be observed after a trauma or surgery. Not all affected pups will exhibit the same severity of clinical signs as these are related to the amount of vWF present, which vary between affected individuals. An affected dog will have a normal PT/aPTT but have prolonged bleeding. When assayed, these dogs usually have low levels of vWF; specific vWF factor can be assayed at a reference laboratory. Performing a functional test like a buccal-mucusal bleeding time prior to surgery is recommended. Some carriers may show clinical signs though dogs with two copies of the mutation tend to be more severely affected. Medications known to interfere with clotting should be avoided. Some dogs may exhibit some improvement when treated with desmopressin acetate.

Some dogs may respond to desmopressin acetate (DDAVP) therapy. In most cases, therapy is limited to supportive care (which can include transfusions if needed) and avoiding surgery. Performing a functional test like a buccal-mucusal bleeding time prior to surgery is recommended.

For Breeders

Planning to breed a dog with this genetic variant?

There are many responsibilities to consider when breeding dogs. Regardless of test results it is important that your dog is in good general health and that you are in a position to care for the puppies if new responsible owners are not found. For first time or novice breeders, advice can be found at most kennel club websites.

This disease is autosomal recessive meaning that two copies of the mutation are needed for disease signs to occur. However, carriers of one copy can show clinical signs. A carrier dog with one copy of the vWD type 1 mutation that does not show clinical signs can be safely bred with a clear dog with no copies of the vWD type 1 mutation. About half of the puppies will have one copy (carriers) and half will have no copies of the vWD type 1 mutation. Puppies in a litter which is expected to contain carriers should be tested prior to breeding. Carrier to carrier matings are not advised as the resulting litter may contain affected puppies. Please note: It is possible that disease signs similar to the ones caused by the vWD type 1 mutation could develop due to a different genetic or clinical cause.

Technical Details

Gene VWF
Variant G>A
Chromosome 27
Coordinate 38,951,839

All coordinates reference CanFam3.1

References & Credit

Credit to our scientific colleagues:

Brooks, M. B., Erb, H. N., Foureman, P. A., & Ray, K. (2001). von Willebrand disease phenotype and von Willebrand factor marker genotype in Doberman Pinschers. American Journal of Veterinary Research, 62(3), 364–369. View the article

Ackerman L. The Genetic Connection. Lakewood: American Animal Hospital Association Press, 2011. View the article