Association Study on IL4, IL13 and IL4RA Polymorphisms in Mite-Sensitized Persistent Allergic Rhinitis in a Chinese Population

BACKGROUND: The IL4, IL13, and IL4 receptor α chain (IL4RA) genes are candidate genes for atopic diseases. We hypothesized that the polymorphisms in these genes are associated with persistent allergic rhinitis (PER). OBJECTIVE: To investigate the association of the potential functional polymorphisms in IL4, IL13, and IL4RA with PER induced by house dust mites in a Chinese population. METHODS: Using the TaqMan method, we genotyped six single nucleotide polymorphisms (SNPs) including C-590T in IL4, C-1055T and Arg130Gln in IL13, and Ile50Val, Ser478Pro and Gln551Arg in IL4RA, in a case-control study of 265 patients with PER and 275 healthy controls. RESULTS: We found that the CT/CC genotypes in IL4 C-590T were associated with a significantly decreased risk of mite-sensitized PER [adjusted odds ratio (OR) = 0.64, 95% confidence interval (CI) 0.45-0.92], compared to the TT genotype. Furthermore, PER patients with CT/CC genotypes had significantly lower serum levels of total IgE than those with TT genotype (P = 0.001). However, there was no significant association of the IL13 and IL4RA polymorphisms with mite-sensitized PER (P>0.05). CONCLUSIONS: Our results suggest that the C-590T polymorphism in IL4 may contribute to the susceptibility to mite-sensitized PER in a Chinese population.