The term Lupus anticoagulant (LAC) indicates a heterogenous class of immunoglobulins that specifically target the epitopes of the negatively charged phospholipid binding proteins, cardiolipins, prothrombin, and β2-glycoprotein I. These antibodies are not specific for SLE, since they are found in other disorders of the immune system with the impairment of the coagulation process [115]. The gene discussed is F2; the disease is systemic lupus erythematosus.