Fibrinogen is a soluble plasma glycoprotein synthesized in the liver. It is composed of two sets of three structurally different subunits: alpha (FGA),beta (FGB),gamma (FGG). Fibrinogen is converted by thrombin into fibrin during blood coagulation. Fibrinogen and fibrin play overlapping roles in blood clotting,fibrinolysis,cellular and matrix interactions,the inflammatory response,wound healing,and neoplasia . FGB is the beta chain of fibrinogen. During conversion of fibrinogen to fibrin,fibrinopeptide B is cleaved from FGB by thrombin. Mutations in the gene of FGB lead to several disorders,including afibrinogenemia,dysfibrinogenemia,hypodysfibrinogenemia and thrombotic tendency.