Antiphospholipid syndrome (APS) is an autoimmune disease characterized by a persistence (≥12 weeks) of moderate to high titers of immunoglobulin isotype G (IgG) and IgM antiphospholipid antibodies (aPL) reactive against either cardiolipin (aCL) or β2 glycoprotein I (aβ2GPI); or positive tests for lupus anticoagulant (LA). The gene discussed is FASLG; the disease is autoimmune polyendocrinopathy.