Aim: The CC chemokine ligand 5 (CCL5), plays a key role in the inflammatory response by recruiting mononuclear cells during tuberculosis (TB) infection. Association studies of CCL5 -28 C>G (rs2280788) polymorphism and TB risk have shown inconsistent and contradictory results among different ethnic populations. The aim of this meta-analysis is to investigate the association between CCL5 -28 C>G polymorphism and TB susceptibility.
Methodology: We performed quantitative synthesis for published studies based upon association between CCL5 -28 C>G polymorphism and TB risk from PubMed (Medline), EMBASE web databases. The meta-analysis was performed and pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated for all genetic models.
Results: A total of six studies including 1324 TB cases and 1407 controls were involved in this meta-analysis. Variant allele (G vs. C: p = 0.257; OR = 1.809, 95% CI = 0.649 to 5.043), heterozygous (CG vs. CC: p = 0.443; OR = 1.440, 95% CI = 0.567 to 3.658) and homozygous (GG vs. CC: p = 0.160; OR = 5.140, 95% CI = 0.524 to 50.404) carriers did not show increased risk compare with those individual with the CC genotype. Similarly, no associations were found in the dominant (GG+CG vs. CC: p = 0.295; OR = 1.802, 95% CI = 0.599 to 5.412) and recessive (GG vs. CC+CG: p = 0.188; OR = 3.533, 95% CI = 0.541 to 23.085) models.
Conclusions: Overall findings of this meta-analysis suggest that genetic polymorphism -28 C>G in CCL5 is not associated with increased TB risk. However, future larger studies with group of populations will be needed to analyze the relationship between the CCL5 -28 C>G polymorphism and risk of TB.