Laboratory criteria are (1) presence of Lupus anticoagulant (LA) in serum or plasma, (2) presence of anticardiolipin (aCL) antibodies IgG and/or IgM isotype in serum or plasma, and (3) presence of anti-β2 glycoprotein-I (aB2GPI) antibodies IgG and/or IgM isotype in serum or plasma. This evidence concerns the gene CD40LG and systemic lupus erythematosus.