Genetic testing for von Willebrand disease: the Canadian experience.

Von Willebrand disease (vWD) is the most common inherited bleeding disorder in humans, but its diagnosis, using clinical criteria and phenotypic hemostasis test results, can be problematic. Since the cloning of the von Willebrand factor ( VWF) gene in the mid-1980s, a significant amount of information has been gathered with respect to the molecular pathology responsible for this trait. The extent of this information, along with major advances in genetic technology, has now made the integration of genetic testing for vWD a feasible option in some instances. This review summarizes the current state of knowledge regarding the genetic causation of the various forms of vWD. We also describe how the genetic analysis of vWD has been initiated within the context of a national network of inherited bleeding disorder clinics. In summary, the aim of this review is to prompt a careful consideration of how genetic testing can find an appropriate role as a complementary diagnostic modality for vWD.