Background and objective: Periodontitis is a chronic inflammatory disease, and genetic factors may have an important role in its severity. Polymorphisms in the promoter regions of the interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-alpha) genes have been reported to cause changes in the production of these cytokines. The aim of this study was to evaluate the possible role of IL-6 (G-174C) and tumour necrosis factor (G-308A) polymorphisms, in the severity of chronic periodontitis in an elderly population.
Materials and methods: In this study, a group of 65 elderly women, comprising 17 patients with moderate chronic periodontitis, 21 with severe chronic periodontitis and 27 healthy patients were selected. DNA was isolated from all subjects, and polymerase chain reaction was used to study the IL-6 and TNF-alpha gene polymorphisms.
Results: The results of this study showed a significant difference in the allele and genotype frequencies of IL-6 gene polymorphism between patients with periodontal disease and controls. Subjects carrying the G/G genotype of IL-6 were most severely affected by periodontitis. The TNF-alpha gene polymorphism showed no association with chronic periodontitis between patients and controls.
Conclusion: The results suggest that the IL-6 gene polymorphism may be associated with chronic periodontitis, and that TNF-alpha gene polymorphism may not be involved in the progression of chronic periodontitis in the population of elderly Brazilian women.