Despite the number of studies that demonstrate increased level of expression of MMP-9 in atherosclerotic lesions [9] as well as in osteoclastogenesis [10], few studies have been designed to reveal the contributory role of MMP-9 in atherosclerosis, or to invest the possibility that MMP-9 may be a key molecule in charge for coupling these two pathologies [11]. This evidence concerns the gene MMP9 and atherosclerosis.