Variations in inflammatory genes are associated with periodontitis

Abstract

BackgroundPeriodontitis is a multi-factorial disease and several risk-factors such as infections, inflammatory responses, oral hygiene, smoke, aging and individual predisposition are involved in the disease. Pathogens trigger chronic inflammation with cytokines release which in turn leads to the destruction of the connective and the teeth supporting bone. The identification of genetic factors controlling oral inflammation may increase our understanding of genetic predisposition to periodontitis.Single nucleotide polymorphisms in the promoter region of Vascular Endothelial Growth Factor, Alpha-1-Antichymotripsin, hydroxy-methyl-glutaryl CoA reductase, Interferon alpha, Interleukin-1 Beta, Interleukin 10, Interleukin 6 and Tumor Necrosis Factor- alpha genes from a case/control study were investigated.ResultsThe C allele of Vascular Endothelial Growth Factor, A allele of Interleukin 10 and GG genotype of Tumor Necrosis Factor-α were individually associated with chronic periodontitis. However, the concomitant presence of the three genetic markers in the same subjects appeared to play a synergistic role and increased several folds the risk of the disease.ConclusionsOur findings offer new tools to implement the screening of unaffected subjects with an increased susceptibility of periodontitis and increase our understanding regarding the genetic inflammatory background related to familiarity of the disease.

Interleukin-6-174G/C Polymorphism Contributes to Periodontitis Susceptibility: An Updated Meta-Analysis of 21 Case-Control Studies

“…After deleting the duplicates, record screen was performed. And 21 studies [5, 14–18, 21, 22, 24–26, 28–36, 38] involving 2422 CP patients and 3373 healthy individuals were identified to be eligible in present meta-analysis. The process of study selection and the reasons for exclusion are listed in Figure 1.…”

“…Of the 21 included studies, 10 studies were conducted in Caucasian population [5, 14, 17, 22, 28–30, 34–36], 6 studies were conducted in Brazilian population [15, 16, 21, 24, 26, 33], 4 studies were conducted in Asian population [18, 25, 32, 38], and 1 study was conducted in Indian population [31]. Seven studies involved nonsmokers as study subjects [5, 15, 22, 24–26, 31].…”

“…Although observational studies have been performed to investigate the association between IL-6 -174 G/C polymorphism and CP, the findings were inconsistent [5, 10, 11, 14–19]. Previous meta-analysis demonstrated by Song et al proposed a link between IL-6 -174 G/C polymorphism and periodontitis susceptibility in Brazilian population [20].…”

“…Nevertheless, this meta-analysis assessed CP and aggressive periodontitis (AP) together, and only 11 studies for CP were involved. In recent years, multiple studies were published regarding the association between IL-6 -174 G/C polymorphism and CP [5, 15, 17, 21–26]. Therefore, in present meta-analysis, 21 studies were included to further discover the role of IL-6 -174 G/C polymorphism in the pathogenesis of CP.…”

Epigenetics in Periodontal Diseases

“…Cytokines are reported as powerful regulatory proteins released by the immune cells influence the behaviour of other cells [5]. SNPs of interleukin (IL-) 1a, IL-1B, IL-4, IL-6, IL-8, IL-18 located in different regions of the cytokine have been shown to affect the risk of the disease in several populations [6]. A study was carried on and seen the polymorphism in IL 1 due to major part that IL 1B played in the development of periodontitis.…”