The laboratory criteria for the diagnosis of APS are the presence of moderate to high levels of IgG and/or IgM antibodies to cardiolipin, IgG and/or IgM antibodies to B2 glycoprotein I, and/or the presence of a lupus anticoagulant [1]. Antibodies to phosphatidylserine/prothrombin complex are one of the noncriteria antiphospholipid antibodies described in “seronegative” APS [4,5]. The gene discussed is CD40LG; the disease is autoimmune polyendocrinopathy.