Gene polymorphisms of pro-inflammatory cytokines may affect the risk of Graves' disease: a meta-analysis

Gene polymorphisms of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1) and interleukin-6 (IL-6) may influence the risk of Graves' disease, but the results of so far published studies remain inconclusive. Therefore, the authors conducted this meta-analysis to assess relationships between TNF-α/IL-1/IL-6 polymorphisms and the risk of Graves' disease by pooling the findings of all relevant studies.

A comprehensive literature searching of Pubmed, Embase, Web of Science and CNKI was conducted by the authors, and twenty-eight studies were found to be eligible for pooled analyses.

The pooled meta-analyses results showed that genotypic frequencies of TNF-α rs1800629, IL-1A rs1800587, IL-6 rs1800795 and IL-6 rs1800796 polymorphisms among patients with Graves' disease and control subjects differed significantly. Moreover, we found that genotypic frequencies of TNF-α rs1800629 and IL-6 rs1800795 polymorphisms among patients with Graves' disease and control subjects in Caucasians differed significantly, and genotypic frequencies of IL-1A rs1800587, IL-1B rs16944, IL-6 rs1800795 and IL-6 rs1800796 polymorphisms among patients with Graves' disease and control subjects in Asians also differed significantly. Nevertheless, we did not detect such genotypic frequencies differences for TNF-α rs361525 and IL-1B rs1143627 polymorphisms.

This meta-analysis suggests that TNF-α rs1800629, IL-1A rs1800587, IL-6 rs1800795 and IL-6 rs1800796 polymorphisms may influence the risk of Graves' disease in overall population. Moreover, TNF-α rs1800629 and IL-6 rs1800795 polymorphisms may influence the risk of Graves' disease in Caucasians, while IL-1A rs1800587, IL-1B rs16944, IL-6 rs1800795 and IL-6 rs1800796 polymorphisms may influence the risk of Graves' disease in Asians.