Association of MMP-1 promoter polymorphism with chronic periodontitis

Objectives: A single nucleotide polymorphism in the promoter region of –1607 bp of the human MMP-1 gene has been found to be associated with an increased risk of various inflammatory diseases and cancer metastasis. The present study aimed to examine the distribution of MMP-1 genotypes in a group of Chinese subjects with chronic periodontitis and periodontally healthy subjects, and evaluated the association between three promoter polymorphisms of the MMP-1 gene and chronic periodontitis susceptibility and/or severity in a Chinese population. Methods: Genomic DNA was obtained from whole blood samples in 60 Chinese subjects with chronic periodontitis and 50 periodontally healthy subjects as controls. MMP-1 promoter fragment was amplified by polymerase chain reaction, and the polymorphisms were analyzed by restriction endonuclease cleavage. The alleles were detected by polyacrylamide gel electrophoresis and visualized with ethidium bromide. Results: In the control subjects, the 2G allele was a frequency of 49%, while in severely diseased patients, the 2G allele was 73.4%. The individuals with the 2G allele seemed to be approximately twice more likely to develop the severe periodontitis than individuals control and mild/moderate(c² =8.754, P=0.003). The genotype of 2G/2G was found in 58.5% of the severe periodontitis, and 24% and 42.1%, respectively, of the control and mild/moderate groups (c² =14.285, P=0.007). Conclusions: The present study suggests that a single nucleotide polymorphism in the MMP-1 promoter region of –1607 bp may be associated with severe chronic periodontitis in Chinese population.