All submissions of the EM system will be redirected to Online Manuscript Submission System. Authors are requested to submit articles directly to Online Manuscript Submission System of respective journal.

Association between IL-21 polymorphism and systemic lupus erythematosus: a meta-analysis

Author(s): J.H. Qi, J. Qi, L.N. Xiang and G. Nie

Several case-control studies have been conducted to investigate the association between Interleukin-21 (IL-21) polymorphisms and systemic lupus erythematosus (SLE) susceptibility, and most of the studies focused on IL-21 rs907715 and rs2221903 polymorphisms. Given the inconsistent results from these studies, the present meta-analysis aimed to obtain a more precise estimate of the association between IL-21 rs907715 and rs2221903 polymorphisms and SLE. Studies regarding these specific polymorphisms and SLE were retrieved from PubMed, Embase, Web of Science, CNKI, and CBM. Data were extracted and meta-analysis was performed using the STATA 12.0 software. For the IL-21 rs907715 polymorphism, seven sets of comparisons involving 7977 SLE cases and 8097 healthy controls were considered. Results showed that there were significant differences in the IL-21 rs907715 genotype distribution between SLE patients andhealthy controls in the comparisons of all genetic models. Upon stratiï¬?ed analysis by ethnicity, a similar result was found in the Caucasian and African-American population. For the IL-21 rs2221903 polymorphism, seven sets of comparisons involving 7990 SLE cases and 8098 healthy controls were considered. Results showed that there were significant differences in the IL-21 rs2221903 genotype distribution between SLE patients and healthy controls in the comparisons of GG versus AA and GG versus GA+AA. Upon stratiï¬?ed analysis by ethnicity, a similar result was found in the Caucasian population. This meta-analysis suggests that the both IL-21 rs907715 and rs2221903 polymorphisms may be associated with SLE susceptibility. As current evidence remains limited, further studies are needed to warrant the association between IL-21 rs907715 and rs2221903 polymorphisms and SLE susceptibility.