Association Of Polymorphisms In The Interleukin-4 Gene Promoter With Childhood Asthma And The Total Serum IgE Level In The Zhuang Population Of Western Guangxi

Objective To determine the frequencies of polymorphisms in the interleukin 4 (IL-4) gene promoter region-589C/T and-33C/T locus in the Zhuang children of westerm Guangxi; And to investigate the correlation between the polymorphisms of IL-4 gene promoter region-589C/T &-33C/T locus and the asthma susceptibility & the total serum IgE level in the Zhuang children.Methods To analyze the polymorphisms of IL-4 gene C-589T and C-33T locus by means of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 72 asthmatic children and 102 normal controls respectively. To determine the total serum IgE level by means of enzyme-linked immunosorbent assay(ELISA) in two groups. The software SPSS 13.0 was used for the statistical analysis. The difference of the genotype frequencies and the allele frequencies between two groups was tested by means of x2 analysis. The comparison of measuring data between two groups was made by t test. The total IgE level serum of different genotypes was compared by means of variance analysis.Results The polymorphisms were found in both of IL-4-589 and-33 locus. The frequencies of polymorphic genotypes of IL-4-589 were CC 5.9%, CT 23.5%, TT 70.6% in normal control group and CC 2.8%, CT 19.4%, TT77.8% in asthmatic group; The allele frequencies were C 17.6%, T 82.4% in normal control group and C 12.5%, T 87.5% in the asthmatic group. The frequencies of genotypes and alleles of IL-4-33 locus in normal control group and in asthmatic group were consistent with those of IL-4-589 locus. There's linkage disequilibrium between two locus and D=0.978. There's no significant difference in the distributions of genotypes and alleles between the asthmatic group and normal control group, and P value is equal to 0.528 and 0.192 respectively. The total serum IgE level of asthmatic group was higher than that of control group, P<0.001. There's no significant difference of the total serum IgE level between different genotypes, P>0.05. The levels of totle serum IgE was higher in asthmatic group than that in control group, when compared the same genotype, P<0.05.Conclusion The polymorphisms were found in both of IL-4-589 and-33 locus in the Zhuang children. There's difference of the distributions of the polymorphism in the IL-4 gene promoter between different ethnic group. IL-4-589C/T was found to be in strong linkage disequilibrium with-33C/T. The polymorphisms in IL-4 gene promoter were specifically not associated with serum IgE concentration or asthma in this study.