Objective To determine the association of one single nucleotide polymorphism loci G 398C in PRM2 with male in‐fertility in Chinese Han population .Methods A total of 386 infertile men were recruited as the observation group and 255 fertile men were recruited as the control group .Routine semen analysis as well as sperm functional parameters such as DNA integrity and nucleoprotein maturity rates were analyzed .Direct sequencing of G398C in PRM2 gene of infertile and fertile men was also conduc‐ted to evaluate the association of G398C SNP loci with male infertility .Results Statistical analysis showed that the frequencies of CC genotype of PRM2 G398C was significantly different between the infertile (11 .92% ) and fertile men (6 .67% ) and it was asso‐ciated with increased risk of male infertility (OR= 2 .002 ,95% CI= 1 .097 -3 .653 ,P< 0 .05) .Moreover ,it was discovered that sperm DNA integrity as well as nucleoprotein maturity rate of CC genotype were dramatically decreased compared with other geno ‐types (P<0 .05) ,which would probably lead to infertility .Conclusion Our results gave the first evidence that PRM 2 G398C poly‐morphism was associated with male infertility in Chinese Han population .

Through comprehensive and systematic collection of existing evidence,systematic review adopts clinical epidemiological methods,strictly evaluates the quality of evidence,qualitatively or quantitatively combines research results,and finally provides a reliable basis for solving a focused clinical problem.The number of systematic reviews has increased rapidly.With references to the Checklist,this review discussed the typical issues with current systematic reviews in nursing,and highlighted the crucial components for reporting systematic reviews at every essential step.