ABSTRACT
<p><b>OBJECTIVE</b>Interleukin-4 plays a key role in the development of asthma. Overseas studies have shown that Q576R polymorphism in the interleukin-4 receptor (IL-4R) gene is related to asthma as well as increased serum IgE levels. This study was designed to investigate the association of Q576R polymorphism in IL-4R gene with childhood asthma and serum IgE levels.</p><p><b>METHODS</b>The polymorphism of IL-4R Q576R was determined by PCR/RFLP and serum total IgE level was measured using ELISA in 94 children with asthma. Sixty-eight healthy children served as controls.</p><p><b>RESULTS</b>The distribution frequency of heterozygous genotype Q576R (41%) and mutant allele R576 (26%) was significantly higher in children with asthma than that of controls (16% each) (P < 0.01; P < 0.05). The total serum IgE level between patients with genotype Q576R and Q576Q was not significantly different (225.78 +/- 51.43 IU/mL vs 163.24 +/- 31.32 IU/mL, P> 0.05).</p><p><b>CONCLUSIONS</b>The mutant R576 allele of IL-4R may be one of the candidate genes for susceptibility to asthma. Allele R576 of IL-4R is related to asthma but is irrelevant to the total serum IgE level in children with asthma.</p>