OBJECTIVETo investigate the association between matrix metalloproteinase 9 gene (MMP9) -1562C/T polymorphism and myocardial infarction (MI) in Uighur population of Xinjiang.

METHODSA total of 347 patients with MI evidenced by coronary arteriography, and 403 controls free from coronary artery disease with normal angiograms were recruited for the study. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect the -1562C/T functional promoter polymorphism of the MMP9 gene. The relationship between the polymorphism and the severity of coronary arterial stenosis was analyzed.

RESULTSThe results showed that the frequency of CT and TT genotypes in patients with MI (27.67%) was significantly higher than that in controls (14.14%). The frequencies of the -1562T allele were 15.71% and 7.56% in the MI group and the control group respectively (chi-square=24.57, P<0.01). Logistic regression analysis indicated that the T allele carriers (CT+TT) had significantly increased risk of MI compared with the CC carriers (OR=2.009, 95%CI: 1.250-3.230). Individuals carrying the -1562T allele with diabetes mellitus were at an increased risk of MI (OR=3.714, 95%CI: 1.299-10.773). The frequencies of CT and TT genotypes were not significantly different among MI patients with one, two and three or more significantly diseased vessels (chi-square=0.491, P=0.782).

CONCLUSIONThe -1562C/T polymorphism in the MMP9 gene promoter is associated with the susceptibility to MI in the Uighur population of Xinjiang. The T allele might be a risk factor of MI. And there was a coordinated effect between the -1562T allele and diabetes mellitus in the development of MI. The -1562C/T polymorphism may not be a predictor of the severity of coronary atherosclerosis.