Abstract: 【Abstract】 Objective In order to find the relationship between MMP-3 5A/6A polymorphism and acute myocardial syndrome. Methods 389 patients were divided into ACS group (n=232) and control group (n=157) according to clinical syndrome and coronary angiography result after admission. Collected two groups’ clinical data and blood sample to test and compare. Results Compare two groups polymorphism we found the rate of patients who carried 5A/6A+5A/6A gene type in ACS group significant higher than control group（36.21% vs 24.84% P=0.001）, and 5A allele frequency also higher in ACS group than in control group（37.93% vs 13.06 P<0.001）. on the other sides compared the MMP-3 serum content between two groups we also found the same result（12.37±2.96 vs 9.59±2.77 P=0.002）.Conclusions The patient who carried MMP-3 5A allele trend to occur ACS than other patients.

Key words: matrix metalloproteinase-3, polymorphism, acute myocardial infarction