Prodynorphin gene promoter polymorphism and temporal lobe epilepsy: A meta-analysis

Previous studies have reported the association of prodynorphin (PDYN) promoter polymorphism with temporal lobe epilepsy (TLE) susceptibility, but the results remain inconclusive. To further precisely evaluate this association, we performed a meta-analysis. Published studies of TLE and PDYN polymorphism up to February 2015 were identified. Subgroup analysis by TLE subtype was performed. Moreover, sensitivity, heterogeneity, and publication bias were also analyzed. Seven case-control studies were finally included in this meta-analysis with 875 TLE cases and 1426 controls. We did not find synthetic evidence of association between PDYN promoter polymorphism and TLE susceptibility (OR=1.184, 95% CI: 0.873-1.606, P=0.277). Similar results were also obtained in non-familial-risk TLE subgroup. However, in the familial-risk TLE subgroup analysis, a significant association was observed (OR=1.739, 95% CI: 1.154-2.619, P=0.008). In summary, this meta-analysis suggests that PDYN gene promoter polymorphism might contribute to familial-risk TLE.