The mechanism of thrombosis in TTP requires not only the interaction of UL-VWF and platelets via the interaction of platelet receptor GP1bα with the A1 domain of VWF but also the activation of platelet fibrinogen receptor, αIIbβ3, thus allowing for fibrinogen binding and subsequent platelet aggregation resulting in microthrombi and thrombus propagation. The gene discussed is GP1BA; the disease is thrombotic thrombocytopenic purpura.