Association between TNF -α ( –308 G → A) Gene Polymorphism and Chronic Periodontitis

Background: Chronic periodontitis is an inflammatory disease caused by environmental and genetic factors. It leads to destruction of tooth supporting tissues and may cause tooth loss. Cytokine TNF-α plays a role in the development of inflammatory lesions and development and progression of the chronic periodontitis disease. Some polymorphisms of this gene are accompanied with change in expression level. The purpose of this study was to investigate the relationship between TNF-α -308 G>A (rs1800629) polymorphism and chronic periodontitis.

Materials and Methods: In this case-control study, 100 patients with chronic periodontitis and 100 normal subjects, referring to the clinic of Zahedan Dental School, were evaluated. Venous blood samples of participants were taken. DNA was extracted using salting-out technique and gene polymorphism was studied at this position using specific primers by T-ARMS PCR method. To investigate the frequency of genotypes and alleles in both groups, χ2 test was employed and p<0.05 was taken to be statistically significant.

Results: The frequencies of AA, GA, and GG genotypes in the patient and control groups were, 1%, 8%, and 91%, and 0%, 16%, and 85%. The frequencies of A and G allele in patient and control groups were 5% and 95%, and 7.9% and 92.1% respectively. There was no significant difference in the frequencies of genotypes and alleles between the groups.

Conclusion: The present study indicates that there is no association between TNF-α (-308 G>A) polymorphism and chronic periodontitis in this population.