Understanding VON WILLEBRANDS DISEASE

VON WILLEBRANDS DISEASE more commonly known as Vwd is a bleeding disorder that was first identified in 1926 by Dr.von Willebrand.  Vwd is an inherited deficiency in one of the clotting factors of the blood and it affects approximately 30 different breeds.  But for purposes here, our focus will be on the Doberman Pinscher. There are two types of Vwd - mild (type 1) and severe (type 2) Dobermans have the mild type.

Vwd is only one of several bleeding disorders that affects the clotting factor.  It is seldom fatal. In fact I have always understood that only about 10 % of the affected dogs ever become clinically affected and have a serious bleeding episode. During the life of an affected dog they can produce enough clotting factor to never had a problem, but if their system is compromised by any other health problem or trauma it is thought to become a contributing factor to more severe complications.. 

Dr. George J. Brewer who is a Professor at the Department of Human Genetics and Internal Medicine, University of Michigan Medical School and his associates discoverd the mutant gene.  Dr. Brewer is a co-founder of Vet Gen working with them to develope the DNA test.   We want to thank these people as well as the following who gave donations to make the grant for the DNA test possible -DPCA, AKC, OFA health foundation, Dr. Morris Animal foundation.

The DNA test gives three designations -  Affected - meaning the dog carries 2 copies of the gene, one copy from each parent and is affected by the disease.  It is thought that 35% of the Dobermans are affected.

Carrier - meaning that the dog only carries one copy of the gene so will not suffer from this bleeding disorder but can carry or pass the mutant gene on to its offspring.Approximately 50% of the Dobermans are carriers

Clear-  The dog did not get a copy of the gene so can't pass it on.  Only 15% are thought to be clears.  I would hope that today with availablity of the test that we are closer to 25% are clear.

From the study it is recommend that breeders work towards a clear dog and this can be accomplished in 2 or 3 generations.  If you always have one clear parent then it is much easier to move to clear dogs.

There was a lot of hysteria and hype when the disease was discovered and the mutant gene identified.  I have found that much of that hysteria and misunderstanding still exist today.  It is the number one question I get asked by the novice looking for a Doberman puppy.  They know nothing about it except that they don/t want it.

I am going to do this article in a 3 part series -  First looking at the disease - What it involves
                                                             Second from a breeders perspective - breeding decisions
                                                             Third Vets and the misunderstandings about Vwd

I am writing this in laymens terms in hopes that everyone will have a much better understanding of Vwd.

http://www.dpca.org/PublicEd/PEC/PECGeneticvWD.html
http://www.vetgen.com/canine-vwd1.html
http://www.chetbacon.com/vWD.htm