RESUMO
Objective To investigate the relationship between polymorphisms of interleukin-4 receptor (IL-4R) gene (E375A, C406R, Q576R) and childhood asthma in Harbin. Methods Ninety-one (91) children with asthma were included, and 42 healthy children were enrolled as control. The genotype polymorphisms of IL-4R were determined by polymerase chain reaction-restriction fragment length polymorphism analysis. Results There was no significant difference in the distributions of the genotypes at both 1 124 A/C polymorphic sites (i.e. E375A polymorphism) and 1 902 A/G polymorphic site (i.e. Q576R polymorphism) in IL-4R between asthmatic group and control group (P > 0.05). There was significant difference in the distributions of the genotypes (CC, CR, RR) on 1 216 T/C polymorphic site (i.e. C406R polymorphism) in IL-4R between the two groups (P < 0.05). The R allele frequency was 22.94% in asthmatic group and 6.58% in control group, with significant difference between the two groups (P < 0.05), but the allele frequencies at this site did not satisfy Hardy-Weinberg equilibrium (P < 0.05). Conclusions Our data suggest that the E375A and Q576R polymorphisms in IL-4R is not associated with the development of asthma in children in Harbin. Further study is needed on the relationship between C406R polymorphism and asthma.