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No association between COMT Val158Met polymorphism and prostate cancer risk: a meta-analysis.

OBJECTIVE
Results from published studies on the association between the catechol-O-methyltransferase (COMT) Val158Met polymorphism and prostate cancer (PCa) risk are inconsistent. To derive a more precise estimate, we performed a meta-analysis.


METHODS
We searched in the PubMed and Elsevier Science Direct database for studies on the association between the COMT Val158Met polymorphism and PCa. We used the odds ratio with 95% confidence interval for PCa risk, detected potential sources of heterogeneity with the Chi-square-based Q-test, performed sensitivity analysis of studies adapted to the Hardy-Weinberg equilibrium.


RESULTS
We found seven case-control studies included 2292 patients and 2158 controls. Fix-effects meta-analysis failed to explore any significant association of PCa with the genetic model and the allelic model of COMT Val158Met. We also did not detect any association in the subgroup analysis by ethnicity in all genetic models. The gene-based analysis suggested that the genetic polymorphism in COMT is not associated with PCa.


CONCLUSIONS
There is no association between the COMT Val158Met polymorphism and PCa.