Interferon gamma +874 T/A polymorphism increases the risk of cervical cancer: evidence from a meta-analysis

Data from previous studies about the association between interferon gamma (IFN-γ) +874 T/A (rs2430561) polymorphism and cervical cancer risk offer controversial results. To obtain a more dependable conclusion, this meta-analysis was performed. We selected eight articles including nine case-control studies with 1,116 cases and 1,290 controls, odds ratios (OR) with 95 % confidence intervals (CI) were used to assess the strength of the association. Subgroup analysis was carried out by ethnicity, source of controls, genotyping methods, and score of quality assessment. Our meta-analysis indicated that the IFN-γ (+874 T/A) polymorphism significantly increased the risk of cervical cancer in the codominant model (TA vs. TT: OR = 1.471, 95 % CI = 1.137-1.903, P = 0.003, I (2) % = 0.0, P Q  = 0.785) and the dominant model (TA + AA vs. TT: OR = 1.399, 95 % CI = 1.097-1.784, P = 0.007, I (2) % = 0.0, P Q  = 0.486) in the overall population. Stratified analysis by ethnicity indicated a significantly increased risk of cervical cancer in Asians in the codominant model (TA vs. TT: OR = 1.494, 95 % CI = 1.069-2.087, P = 0.019, I (2) % = 0.0, P Q  = 0.440) and the dominant model (OR = 1.455, 95 % CI = 1.062-1.993, P = 0.019, I (2) % = 42.9, P Q  = 0.154). Thus, the IFN-γ (+874 T/A) polymorphism is likely to increase the risk of cervical cancer. Because of the limited studies and sample sizes included in our meta-analysis, further well-designed and large-scale studies are demanded to confirm our results.