Association of polymorphism rs1800629 of the TNF-α G-308A gene in patients with recurrent aphthous stomatitis

Abstract

The heterogeneity of etiology and pathogenesis leads to the understanding of recurrent aphthous stomatitis (RAS) as a multifactorial pathology with the absence of the gene that causes the disease. Currently, in the pathogenesis of RAS, an imbalance between pro- and anti-inflammatory cytokines with a prevalence of the concentration of pro-inflammatory mediators involved in the implementation of the main mechanism of pathogenesis of RAS — inflammation has been proven. Changes in the expression of cytokines in various polymorphic variants can affect the occurrence and level of generalization of inflammation, ultimately determining the scenario for the development of pathology. Information about genetic defects that determine the phenotype of pathology with a hereditary determinant will help expand the understanding of the etiopathogenesis of the disease and determine the approach to personalized therapy. All of the above determines the importance of studying the individual genetic profile of proinflammatory cytokine genes in patients with RAS. Purpose — to assess the role of the rs1800629 polymorphism of the proinflammatory cytokine gene TNF-α G-308A in patients with RAS.
Methods.
To obtain genomic DNA, we used the venous blood of patients obtained during the height of the disease. DNA concentration was measured using genomic-cell technology. The deviation of the distributions of genotypes of the studied DNA polymorphisms from the canonical Hardy-Weinberg (RHB) distribution was assessed using the GenePop (Genetics of Population) program for analyzing genetic data. The frequency of allele variants and genotypes was calculated. The significance of differences between groups in the frequencies of alleles and genotypes of the studied polymorphism G-308A of the TNF-α gene was assessed using the χ2 test.
Results.
As a result of the study, the prevalence of polymorphisms in the gene for the anti-inflammatory cytokine of the polymorphic variant rs1800629 of the TNF-α gene of the locus G-308A was established. The data obtained made it possible to establish the association of polymorphisms with the development of the disease and the severity of the clinical course of the multifactorial disease. The frequencies of the A allele and its and heterozygous A/G genotype are increased in patients with RAS, while the frequencies of the wild-type G allele and its homozygous G/G genotype are reduced. The OR calculation showed that the highly productive A allele and its heterozygous variant (G/A) are associated with RAS and its severity, while the wild G allele and its homozygous G/G genotype are protective against the development of the disease.
Conclusions.
Polymorphism of the 308 G/A TNF-α gene, encoding the expression of the proinflammatory cytokine TNF, is pathogenetically significant in the development of RAS. Polymorphism of 308 G/A rs1800629 of the TNF-α gene, carriage of allele A and homozygous genotype G/A can be considered as a hereditary predisposition to RAS and a criterion for the severity of its clinical course.