Type 1 and type 3 vWD are characterizedby partial and complete deficiency of vWF, respectively.Functional deficiency of vWF is characteristic of type 2vWD, which is further classified as 2A, 2B, and 2M basedon defective interaction with platelets, and as 2N based ondefective binding to the FVIII molecule. The gene discussed is VWF; the disease is von Willebrand disease (hereditary or acquired).