Association between MMP-1 Gene Promoter Genetic Variation and Chronic Periodontitis Susceptibility in the Iranian Population
Background: A genetic variation was described in the promoter region of the human MMP-1 gene, and this genetic variation has been associated with risk of inflammatory diseases. We aimed to evaluate the association between the MMP-1 promoter gene genetic variation (1G/2G at -1607) and incidence and severity of chronic periodontitis (CP) susceptibility in an Iranian population. Methods: In this analytic cross-sectional study, 100 Iranian subjects were allocated to case (with CP, n=50) and control (with normal periodontium, n=50) groups. Clinical indices (plaque index, clinical attachment loss, bone loss, and probing pocket depth) were measured before genetic analysis. Genomic DNA was obtained from whole blood samples. MMP-1 promoter genetic variations (-1607) were genotyped using PCR-RFLP method and the clinical and genetic data were analyzed with t, Chi-square, Mann- Whitney, and Fisher’s exact tests. Results: Genotype analyses revealed no significant differences in the distribution of MMP-1 promoter (G1/G2) genotype (at -1607 locus) between the two groups (P=0.495). There was significant correlation between MMP-1 genotype 1G/2G with clinical attachment loss and age in the CP group (P=0.046 and 0.047 respectively), but no significant correlation was found between MMP-1 genotype 1G/2G and other periodontal indices (bone loss, probing pocket depth and plaque index). Conclusion: MMP-1 genetic variation does not increase the susceptibility to chronic periodontitis in patients CP, while there is an association between attachment loss and MMP-1 genetic variation.