Association between rheumatoid arthritis and genetic variants of natural resistance-associated macrophage protein 1 gene: A meta-analysis.

AIM: To evaluate the association between natural resistance-associated macrophage protein 1 (NRAMP1) polymorphisms and rheumatoid arthritis (RA). METHOD: All related studies were retrieved and screened from PubMed, CNKI and Web of Science. Pooled odds ratios (ORs) and 95% CIs were assessed for the strength of association between NRAMP1 and RA. Publication bias was measured by Begg's funnel plot and Egger's regression test. The robustness of this meta-analysis was detected by sensitivity analysis. RESULTS: A total of five eligible publications were included in the present meta-analysis. The polled data showed no association between RA and NRAMP1 D543N and 1729 + 55del4 in the allele model. However, the relationship between RA and NRAMP1 INT4 was statistically significant (OR 1.65, 95% CI 1.14-2.38). Genotypic analysis demonstrated that there were no associations between RA and NRAMP1 D543N, 1729 + 55del4 and INT4 in homozygous comparison (D543N: OR 0.97, 95% CI 0.15-6.09; 1729 + 55del4: OR 1.19, 95% CI 0.29-24.88; INT4: OR 3.18, 95% CI 0.62-16.26), dominant model (D543N: OR 1.04, 95% CI 0.61-61.78; 1729 + 55del4: OR 1.41, 95% CI 0.81-2.47; INT4: OR 1.22, 95% CI 0.72-2.06) and recessive model (D543N: OR 0.93, 95% CI 0.15-5.91; 1729 + 55del4: OR 0.99, 95% CI 0.26-3.86; INT4: OR 2.95, 95% CI 0.61-14.16). In heterozygous comparison, it no association was shown between RA and NRAMP1 D543N and INT4, excepting NRAMP1 1729 + 55del4 (OR 1.73, 95% CI 1.17-2.56). Further subgroup analysis indicated that NRAMP1 1729 + 55del4 and INT4 were related to RA in Asia and in the Hardy-Weinberg equilibrium group. There exists no publication bias in this meta-analysis. CONCLUSION: This meta-analysis indicated that NRAMP1 1729 + 55del4 and INT4 confer susceptibility to RA.