This is the case of the primary antiphospholipid syndrome: two separate cohorts from Southern Italy show that primary antiphospholipid antibody (PAPS) patients carrying the MTHFR TT genotype developed their vascular occlusion 16 years and 27 years earlier than PAPS carriers of MTHFR CT + CC [68,69]. Here, MTHFR is linked to vascular occlusion disorder.