Análise do polimorfismo-1612 no gene da MMP-3 e 509 no gene do TGF-b1 em indivíduos com doença periodontal crônica

Abstract

Matrix metalloproteinases (MMPs) degrade a range of extracellular matrix proteins and have been implicated in connective tissue destruction during cancer invasion, cartilage destruction in arthritis, atherosclerotic plaque rupture, and periodontal tissues destruction. Recently, genetic variances have been detected in the promoter of a number of MMPs genes. These genetic polymorphisms have been shown to have allele-specific effects on the transcription activities of MMP gene promoters, and to be associated with susceptibility and/or severity to several diseases. Similarly, genetic polymorphisms have been found in the gene promoter of the transforming growth factor-b1 (TGF-b1), an important growth factor reponsible to increase the collagen production. These alterations could contribute to the imbalance between the synthesis and degradation of the extracellular matrix components. Presently, periodontal disease represents the main factor responsible for loss of teeth in adults. The role of bacterial in the initiation of periodontitis is very well documented, but the activation of the host defense cells required to release mediators that stimulate the pathway connective tissue breakdown is unclear. Likewise, the aim of our study was to detect genetic polymorphisms in the gene promoter of MMP-3 and TGF-b1 and to associate with susceptibility of the chronic periodontal disease in a Brazilian population. Subjects were divided into two groups: Control and Periodontal Disease. Genomic DNA from jugal mucosa was amplified by PCR, digested by RFLP, and analyzed by electrophoresis. Statistical analysis (p<0.05%) was made through c2-test. Statistically significant difference was observed for allelic and genotype frequencies of the TGF-b1 polymorphism between the two groups (p<0.05%). Individuals bearing T/T genotype seem to have a bigger risk in developing the periodontal disease. Statistically significant differences were observed for the genotypes frequencies in the MMP-3 gene between the two groups (p<0.05%). Individuals bearing 5A/5A genotype seem to also have a bigger risk in developing the periodontal disease. However, no statistically significant differences were observed for allelic frequencies in the MMP-3 gene (p>0.05%). In the conclusion, polymorphisms in the MMP-3 (-1612 5A/6A) and TGF-b1 (-509 C/T) genes seem to be associated with disease periodontal chronic in Brazilian population.