Prolongation of aPTT and PT, decreased platelets count, plasma fibrinogen level, prothrombin, factor VIII, plasminogen and antithrombin III activities were observed transiently during acute phase of DHF [9, 20, 25] and they characterize hemorrhagic diathesis of DVI severe patients [3, 4, 20, 21, 25]. The gene discussed is F2; the disease is hemorrhagic disease.