The main antigenic targets of these antibodies are β2GPI and prothrombin, which together account for more than 90% of the antibody-binding activity in APS; antigenic targets also include tissue plasminogen activator (tPA), phosphatidylserine (PS), plasmin, annexin 2, activated protein C (APC), thrombin, antithrombin III (AT-III), and annexin V [4,5,6,7,8,9,10]. The gene discussed is SERPINC1; the disease is autoimmune polyendocrinopathy.