The aim of this study was to analyze the occurrence of the -1612 5A/6A, -376C/G, and Glu45Lys polymorphisms of MMP3 and the -1562C/T and R279Q polymorphisms of MMP9 and their relation to the risk of coronary heart disease (CHD; stenosis >/=50% of the diameter in at least one major coronary artery) in a Chinese Han population.