OBJECTIVETo investigate the association between a -799C/T polymorphism in the promotor region of matrix metalloproteinase-8 (MMP-8) gene and instability of carotid plaque in Chinese Han population.

METHODSA total of 451 acute infarction patients from the Department of Neurology of Taizhou Hospital were divided into carotid vulnerable plaque group and carotid stable plaque group according to the results of carotid B-mode ultrasonography. Serum MMP -8 level was measured by the means of enzyme-linked immunosorbent assay (ELISA). At the same time, the MMP-8 -799C/T polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

RESULTSSerum level of MMP-8 in the carotid vulnerable plaque group was higher than that in the carotid stable plaque group (t= 2.894, P= 0.004). The genotype distribution of -799C/T polymorphism between the two groups was significantly different (Chi-square = 13.65, P= 0.000). Serum level of MMP-8 in patients with TT genotype was higher than that in patients with CC genotype (t= 3.141, P= 0.001).

CONCLUSIONThe present study suggested that serum level of MMP-8 and the -799C/T polymorphism of MMP-8 gene are associated with carotid vulnerable plaque in Chinese Han population, and the T allele may be a predictor for the susceptibility of carotid vulnerable plaque.