Allelic polymorphism C-590T of the IL4 gene as a probable genetic marker for the increased predisposition to the development of recurrent episodes of acute obstructive bronchitis in children

Abstract

Acute respiratory infections (ARIs) hold the first place among all infections throughout the world. ARIs are frequently complicated by the development of acute obstructive bronchitis (AOB). According to different authors, the frequency of developing AOB due to ARIs in children ranges from 5 to 40%. The growing occurrences of ARIs in children and the formation of bronchoobstructive syndrome that frequently ends up in the development of bronchial asthma, leading children to invalidity, specify a new priority research area—molecular genetic markers sought for to identify an increased predisposition to certain socially important illnesses. The molecular-genetic testing of the polymorphic C-590T locus of the IL4 gene as the marker of increased predisposition to the development of recurrent episodes of AOB were conducted in 31 children with frequent ARIs and recurrent episodes of AOB and in 50 general-population control subjects. The level of IgE in the blood serum was studied in 31 children with frequent recurrent episodes of AOB and compared with the data of 35 control children with acute bronchitis. The comparative molecular genetic analysis of the results in children with recurrent episodes of AOB and the data obtained from the subjects of a general population control group has shown that the frequency of the CT genotype at the polymorphic C-590T locus of the IL4 gene was noticeably higher in children with recurrent AOB episodes. The markedly higher frequency of the CC genotype at the polymorphic C-590T locus of the IL4 gene was recorded in the control group subjects and compared to the data of children from the main group. It was established that carrying the 590 CT genotype with the allelic polymorphism of the IL4 gene increases the risk of recurrent episodes of AOB in children by three times. The level of IgE in the blood serum in the majority of sick children from the main group was four times higher than in the control children.