CXCL12 G801A polymorphism and breast cancer risk: a meta-analysis

The G801A polymorphism in the CXCL12 gene has been implicated in breast cancer risk. However, the published findings are inconsistent. We therefore performed a meta-analysis to investigate this relationship. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the association. The pooled ORs were performed for codominant model, dominant model, and recessive model, respectively. Five published case-control studies, including 1,058 breast cancer cases and 1,023 controls were identified. No study had a deviation from the Hardy-Weinberg equilibrium (HWE) in controls. We found that the CXCL12 G801A (rs1801157) polymorphism was associated with a significantly increased risk of breast cancer risk when all studies were pooled into the meta-analysis (codomiant model: AA versus GG, OR = 1.64, 95% CI = 1.16-2.33; GA versus GG, OR = 1.42, 95% CI = 1.18-1.71; dominant model: AA/GA versus GG, OR = 1.44, 95% CI = 1.21-1.72). Furthermore, Egger's test did not show any evidence of publication bias (P > 0.05 for the dominant model). In conclusion, the results suggest that the CXCL12 G801A polymorphism may be a low-penetrant risk factor for developing breast cancer.