Altered PAI-1 levels observed in animal models have been associated with a diverse spectrum of diseases, low levels correlate with accelerated atherosclerosis and a defect in local angiogenesis; in counterpart, higher PAI-1 levels are found to be produced by malignant cells leading to a hypercoagulation state and in multiple sclerosis tissue interfering with fibrin degradation and contributing to axonal damage [5, 7]. The gene discussed is SERPINE1; the disease is multiple sclerosis.