Association between the interleukin 4 gene -590C>T promoter polymorphism and asthma in Xinjiang Uighur children.

ABSTRACT

We investigated the association between the interleukin 4 gene (IL-4) -590C>T polymorphism and forced expiratory volume in one second (FEV1) values, immunoglobulin E (IgE) levels, and susceptibility to asthma in Uighur children. IL-4 -590C>T frequencies were analyzed in 38 bronchial asthmatic patients and 35 non-asthmatic controls. Polymerase chain reaction and direct sequencing were applied to determine the residue at position -590 of IL-4. Total serum IgE levels were detected by enzyme-linked immunosorbent assay, while lung function was examined by professionals. There were significant differences in the distribution of IL-4 -590C>T genotypes and alleles between patient and control groups (genotypes chi-square = 11.476, P < 0.05; alleles chi-square = 14.572, P < 0.05). Frequencies of CC, CT, and TT genotypes were 21, 29, and 50% among patients, and 49, 37, and 14% among controls, respectively, indicating that the T allele was significantly more frequent in the asthma group than in the control group. Total serum IgE levels were significantly higher (P < 0.05) and FEV1 values were significantly lower (F = 13.294, P < 0.05) in patients than in control subjects of the same genotype. In conclusion, the IL-4 -590C>T polymorphism is related to bronchial asthma in Uighur children, and the T allele may constitute a susceptibility factor in this group. Furthermore, this genetic variant can result in raised IgE levels and decreased FEV1 values, suggesting that both factors are associated with bronchial asthma in Uighur children.