Antiphospholipid syndrome (APS) is an acquired autoimmune disorder first described in 1983, characterised by thrombosis (in the venous, arterial, or microvascular circulation) and pregnancy morbidity, in the setting of persistently positive antiphospholipid antibodies (aPL): lupus anticoagulant (LA), anti-beta 2 glycoprotein 1 (anti-ß2GP1), and anticardiolipin antibodies (aCL). This evidence concerns the gene FASLG and deep vein thrombosis.