Laboratory criteria for formal APS classification currently include three aPL assays: one based on coagulation tests to reveal the presence of lupus anticoagulant (LA) and two solid phase assays to detect IgG/IgM antibodies targeting cardiolipin (CL)/beta2 glycoprotein I (β2GPI) complexes or β2GPI alone (Table 1). The gene discussed is CD40LG; the disease is autoimmune polyendocrinopathy.