G308a Tnf-Α Gene Polymorphism in Children's Recurrent Bronchitis and its Effect on Tnf-Α Interleukin Synthesis

Abstract

The aim of this study was to study the frequency of polymorphic alleles and genotypes G-308A of the TNF-α gene, as well as their influence on the synthesis of TNF-α in patients with RB. The study was carried out in 119 children aged 2 to 7 years with RB (main group). All patients of the main group were divided into 2 subgroups: subgroup I of 62 children with recurrent bronchitis, subgroup II consisted of 57 patients with RB on the background of LGD. The control group consisted of 110 conventio healthy children of the same age. The distribution of alleles and genotypes of the TNF-α gene in the studied groups of patients with RB and RB on the background of LGD and the control group corresponded to the Hardy-Weinberg equilibrium. In the active phase of RB, the level of TNFα was 6.7 times higher than in the control group. In children of RB against the background of LGD, a 4.9-fold increase in the TNFα concentration was revealed. In patients of subgroup II in the remission phase, there was a tendency towards a decrease in TNFα (P> 0.49), while in patients of subgroup I in the remission phase, the level of TNFα was significantly reduced (P <0.0001). The data obtained indicate that in RB patients against the background of LGD, the process of acute immune inflammation lasts longer. The highest frequency of the G allele and the G/G genotype was noted in the studied groups. At the same time, the indices of the G allele and the homozygous G/G genotype in patients of the II subgroup tended to decrease in comparison with the control group, i.e. this genotype has a protective effect. The minor allele A and the heterozygous G / A genotype were greatest in subgroup II (17.7% in subgroup I and 21% in subgroup II) compared to conditionally healthy children. At the same time, the chance of developing of RB carriers of the heterozygous genotype G / A in subgroup II is 1.6. Not a single case of carriage of mutant genotypes A / A was revealed among patients with RB and healthy people. The presence of the A allele was accompanied by an increase in TNFα production in RB patients against the background of LGD, regardless of the phase of the disease.