Relationship between MCP-1 promoter -2518 A/G gene polymorphism (rs1024611) and systemic lupus erythematosus/lupus nephritis

Results from the published studies on the association between monocyte chemoattractant protein-1 (MCP-1) promoter -2518 A/G (rs1024611) gene polymorphism and systemic lupus erythematosus (SLE)/lupus nephritis (LN) are still conflicting. This meta-analysis was performed to evaluate the relationship between MCP-1 A/G gene polymorphism and SLE/LN and to explore whether MCP-1 A allele, AA genotype or GG genotype could become a predictive marker for SLE/LN risk. Association studies were identified from the databases of PubMed, Embase, Cochrane Library and CBM-disc (China Biological Medicine Database) as of 1 January 2014, and eligible investigations were synthesized using meta-analysis method. Results were expressed with odds ratios (OR) for dichotomous data, and 95% confidence intervals (CI) were also calculated. Sixteen investigations were identified for the analysis of association between MCP-1 A/G gene polymorphism and SLE, consisting of 2425 patients with SLE and 2567 controls. In the overall populations, Asians, Caucasian population, the association between MCP-1 A/G gene polymorphism and SLE susceptibility was not found. Interestingly, a trend toward an association between A allele/AA genotype and LN risk was observed in overall populations, although there was no statistical difference. However, this meta-analysis indicated that AA genotype was associated with LN risk in Caucasians (OR = 0.71; 95% CI: 0.54-0.93; p = 0.01). In conclusion, our results indicate that AA homozygous might be a significant genetic molecular marker to predict the SLE patients developing into LN in Caucasians. However, more investigations are required to further clarify this association.