Association of matrix metalloproteinase (MMP)-1, 3, 9, interleukin (IL)-2, 8 and cyclooxygenase (COX)-2 gene polymorphisms with chronic periodontitis in a Chinese population.

Chronic periodontitis (CPs) could result in damage of periodontal tissues, loss of teeth and impose troublesome hindrance to restore teeth satisfyingly as well. Functional gene polymorphisms of matrix metalloproteinases, cytokines and cyclooxygenase-2 have been found to play important roles in periodontitis. This study was to investigate the association between MMP-1-1067, MMP-3-1171, MMP-9-1562, IL-2-330, IL-8-251, COX-2-765 polymorphisms, and the susceptibility to CP in a Chinese population. A total of 122 patients with CP were evaluated for MMP-1, MMP-3, MMP-9, IL-2, IL-8 and COX-2 genetic polymorphisms and were compared with 532 healthy control subjects using PCR-RFLP analysis. Clinical periodontal parameters were recorded. Serum levels of MMP-1, MMP-3, MMP-9, IL-2, IL-8 and COX-2 were measured by ELISA. The data were analyzed by chi-square, logistic regression and Mann-Whitney-U-tests and t test. There were significant differences between CP patients and healthy subjects in the genotype distribution and allele frequency of MMP-3-1171, MMP-9-1562, IL-2-330, IL-8-251 and COX-2-765 genetic polymorphisms. Significant difference between patients and controls were also observed for MMP-1-1067 genotype frequency, but not for allele frequency. Differences between rare allele carriage rates of CP and healthy groups regarding all the genetic polymorphisms in our study were significant (p<0.05). Serum levels of all the cytokines were higher in the CP patients compared to healthy subjects. These data show that MMP-1-1067, MMP-3-1171, MMP-9-1562 and IL-8-251 polymorphisms are associated with susceptibility to CP. MMP-1-1067 2G, MMP-3-1171 6A, MMP-9-1562 T and IL-8-251 A allele are associated with decreased susceptibility to CP in Chinese population.