Association of Interferon-gamma Gene Polymorphism (+874 A/T) and Oral Lichen planus susceptibility: Systematic Review and Meta- Analysis

Background and objectives: Most studies have identified interferon-gamma (IFN-γ) as a key role in the pathogenesis of oral lichen planus (OLP). Recent studies have also shown a link between IFN-γ (+874 A/T) gene polymorphism and OLP. The purpose of the present meta-analysis is to investigate the relationship between IFN-γ (+874 A/T) gene polymorphism and susceptibility to OLP. Methods: A systematic search of resources to investigate the association between IFN-γ and OLP from Google scholar, PubMed, Embase, Cochrane, Scopus, Proquest, Ovid and Web of science (from 2000 to April 2019) completed. Two individuals independently assessed the quality of the articles. Endnote X5 resource management software was used to organize, study titles and abstracts as well as identify duplicates. A random effect model was also used to perform the meta-analysis. Results: Four IFN-γ (+874 A/T) polymorphism studies with 297 patients in the case group and 621 healthy controls in the 4 different countries were included. After metaanalysis, a significant association was found between IFN-γ polymorphism (+874 A/T) and OLP. (T vs A: odds ratio (OR) = 1.62; 95% CI = 1.28-2.04; TT vs AA: o‎r = 2.67; 95% CI = 1.6- 4.45; AT vs AA: o‎r = 1.56; 95% CI = 1.6- 4.45; TT vs AT + AA: o‎r = 1.73; 95% CI = 1.13-2.64; AT + TT vs AA: o‎r = 1.75; 95% CI = 1.28-2.43) Conclusion: Based on this meta-analysis, there was a positive relationship between IFN- γ (+874 A/T) gene polymorphism and the risk of OLP. The findings showed that increasing TT genotypes significantly increased susceptibility to OLP in comparison with other genotypes.