Polymorphism in the tumor necrosis factor-alpha gene (TNFA -308 G/A) is not associated with susceptibility to chronic periodontitis in a Brazilian population

Abstract

Objective: Tumor necrosis factor-alpha (TNF-α) is a major mediator of the immune-inflammatory response and may play an important role in the pathogenesis and progression of chronic periodontitis. Polymorphisms in the promoter of the TNFA gene have been associated with some types of inflammatory diseases. The present study investigated the association between a single-nucleotide polymorphism (SNP) of the TNFA (G-308A) gene and chronic periodontitis in Brazilians. Methods: One hundred and thirteen (113) over 25 years were divided according to the severity level of periodontal disease: 44 healthy individuals (control group), 31 subjects with moderate and 38 patients with severe periodontitis. Genomic DNA was obtained from epithelial cells. The samples were analyzed for TNFA (G-308A) polymorphism using polymerase chain reaction-restriction fragment length polymorphism techniques. The significance of the differences in the genotype frequencies of the polymorphism was assessed by Chi-square test (p<0.05). Results: No significant differences in the genotype distribution and allele frequency were found between control and groups with periodontitis. Conclusion: It was concluded that TNFA (-308) polymorphism was not associated with chronic periodontitis. Other polymorphisms in this or/and other genes of the host inflammatory response might be involved in determining susceptibility to periodontitis in the study population.