Interleukin-4 receptor α-chain polymorphisms and susceptibility to allergic rhinitis: a meta-analysis.

Several polymorphisms in interleukin-4 receptor α-chain (IL-4RA) have been implicated in susceptibility to allergic rhinitis (AR), but the results are inconclusive. This meta-analysis was aimed to clarify the impact of IL-4RA polymorphisms on AR risk. Pubmed, EMBASE and Cochrane Library were searched until 2 October 2013 for eligible studies on IL-4RA polymorphism. Data were extracted, and pooled odd ratios (ORs) as well as 95 % confidence intervals (95 % CIs) were calculated. Ten studies with 1,552 AR patients and 1,473 controls were included. The results indicated that IL4RA Gln551Arg polymorphism was associated with AR susceptibility in Asian (AG vs. AA OR = 1.63, 95 % CI 1.17-2.28, I (2) = 57 %; GG vs. AA, OR = 1.69, 95 % CI 1.00-2.86, I (2) = 7 %; AG + GG vs. AA, OR = 1.68, 95 % CI 1.18-2.39, I (2) = 64 %; GG vs. AG + AA, OR = 1.47, 95 % CI 0.87-2.49, I (2) = 0 %; G vs. A, OR = 1.54, 95 % CI 1.14-2.10, I (2) = 64 %) but not in Caucasian. IL4RA Ile50 Val as well as Ser478Pro polymorphisms were not associated with AR susceptibility both in Asian and in Caucasian. Gene-gene and gene-environment interactions should be investigated in the future.