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[Association of male infertility with (CAG)n polymorphism of the androgen receptor gene: a meta-analysis].

OBJECTIVE
To assess the association of male infertility with CAG repeat polymorphism of the androgen receptor (AR) gene by meta-analysis.


METHODS
We identified the case-control studies on the relationship of male infertility with CAG repeats of the AR gene by searching Medline/PubMed and CBM databases, and conducted meta-analysis on the data obtained with the RevMan 4.2 software.


RESULTS
Thirty-two eligible articles were selected in this study, including 3,153 idiopathic infertile men and 2,314 controls. The combined data statistics showed that all the infertile men had a significantly higher mean of CAG repeats than the controls (SMD = 0.27, 95% CI: 0.17-0.37, P < 0.01). The specific SMD between the infertile patients and controls was 0.29, 95% CI: 0.08-0.50 for the azoospermic men, 0.27, 95% CI: 0.13-0.41 for the moderate oligozoospermic men, and 0.18, 95% CI: 0.02-0.33 for the severe oligozoospermic cases. The results of sensitivity analyses were consistent with those mentioned above.


CONCLUSION
The increased length of CAG repeats in the AR gene may be correlated with the risk of the impairment of spermatogenesis.