In the guidelines of the American Society of Hematology, the International Society on Thrombosis and Haemostasis, the National Hemophilia Foundation, and the World Federation of Hemophilia for the diagnosis of hereditary von Willebrand disease, a bleeding tendency and a decrease in VWF:RCo and/or VWF:Ag are essential criteria for its diagnosis while these are not included in the diagnosis of AVWS [20]. The gene discussed is VWF; the disease is hemophilia.