Abstract: Objective　To evaluate the effect of two SNPs （rs3219489 and rs10527342） of MUTYH gene on primary male infertility and sperm DNA integrity and their interaction with smoking and alcohol consumption.Methods　245 primary male infertile patients who received treatment in the Outpatient Department of the Center for Reproductive Medicine in the General Hospital of Ningxia Medical University from August 2011 to December 2012 were selected as case group,including 166 patients with oligoasthenospermia （oligoasthenospermia subgroup） and 79 patients with normozoospermia male infertility （normozoospermia subgroup）,and 329 healthy males with reproductive history from the physical examination of the hospital in the same period were selected as control group.PCR-RFLP was employed to analyze the genotype distribution and allele frequency of MUTYH rs3219489 and rs10527342.The damage degree of DNA was determined by sperm chromatin dispersion and was manifested by sperm DNA fracture index （DFI）.Results　Control group and case group were not significantly different in the distribution of GG,CG and CC genotypes of MUTYH rs3219489 （P>0.05）,but were significantly different in the frequency of CG+CC genotype and G and C allele frequency （P<0.05）.Control group and case group were not significantly different in the distribution of AP,AP and PP genotypes,the frequency of AP+PP genotype and the A and P allele frequency of MUTYH rs10527342（P>0.05）.Control group,oligoasthenospermia subgroup and normozoospermia subgroup were not significantly different in the distribution of GG,CG and CC genotypes of MUTYH rs3219489 （P>0.05）,but were significantly different in the frequency of CG+CC genotype and the G and C allele frequency （P<0.05）.The three groups were not significantly different in the distribution of AA,AP and PP genotypes,the frequency of AP+PP genotype and the A and P allele frequency of MUTYH rs10527342（P>0.05）.Case group was higher than control group in sperm DFI〔（46.2±22.3）% vs.（21.4±9.2）%〕（P<0.05）.Oligoasthenospermia subgroup and normozoospermia subgroup were higher than control group in sperm DFI,and oligoasthenospermia subgroup was higher than normozoospermia subgroup in sperm DFI （P<0.05）.There were no significant differences in sperm DFI among patients with different genotypes of MUTYH rs3219489 and rs10527342 （P>0.05）.Moderate linkage disequilibrium existed between MUTYH rs3219489 and rs10527342 （D’=0.749，r2=0.289）.There were no interaction of MUTYH rs3219489 and rs10527342 with smoking and alcholic consumption （P>0.05）.Conclusion　C allele of MUTYH rs3219489 may be a protective factor for primary male infertility,and MUTYH rs10527342 may have correlation with primary male infertility.The increase of sperm DFI may cause the increase in the risk of primary male infertility,and rs3219489 and rs10527342 may have no correlation with the integrity of sperm DNA and have no interaction with smoking and alcoholic consumption.

Key words: Infertility,male, MUTYH gene, Polymorphism,single nucleotide, Spermatozoa, DNA

摘要： 目的　探讨MUTYH基因rs3219489、rs10527342位点单核苷酸多态性（SNPs）对原发性男性不育症和精子DNA完整性的影响及其与吸烟、饮酒的交互作用。 方法　选取2011年8月—2012年12月在宁夏医科大学总医院生殖医学中心门诊就诊的245例原发性男性不育症患者为病例组，其中少精弱精症患者166例（少精弱精症亚组）、精液指标正常男性不育症患者79例（精液指标正常亚组）；另选取同期在宁夏医科大学总医院体检健康且有生育史的男性329例为对照组。采用聚合酶链式反应-限制性片段长度多态性（PCR-RFLP）技术分析MUTYH基因rs3219489、rs10527342位点基因型分布和等位基因频率。采用精子染色质扩散（SCD）试验检测精子DNA损伤程度，采用精子DNA断裂指数（DFI）表示。结果　对照组与病例组MUTYH基因rs3219489位点GG、CG、CC基因型分布比较,差异无统计学意义（P>0.05）； CG+CC基因型频率和G、C等位基因频率比较,差异有统计学意义（P<0.05）。对照组与病例组MUTYH基因rs10527342位点AA、AP、PP基因型分布，AP+PP基因型频率和A、P等位基因频率比较,差异均无统计学意义（P>0.05）。对照组、少精弱精症亚组与精液指标正常亚组MUTYH基因rs3219489位点GG、CG、CC基因型分布比较，差异无统计学意义（P>0.05）；CG+CC基因型频率和G、C等位基因频率比较,差异有统计学意义（P<0.05）。3组MUTYH基因rs10527342位点AA、AP、PP基因型分布，AP+PP基因型频率和A、P等位基因频率比较,差异均无统计学意义（P>0.05）。病例组精子DFI〔（46.2±22.3）%〕高于对照组〔（21.4±9.2）%〕（P<0.05）。少精弱精症亚组与精液指标正常亚组精子 DFI高于对照组，少精弱精症亚组精子DFI高于精液指标正常亚组（P<0.05）。MUTYH基因rs3219489、rs10527342位点不同基因型原发性男性不育症患者精子 DFI 比较,差异无统计学意义（P>0.05）。MUTYH基因rs3219489位点与rs10527342位点间存在中度连锁不平衡（D’=0.749，r2=0.289）。MUTYH基因rs3219489、rs10527342位点与吸烟、饮酒均不存在交互作用（P>0.05）。 结论　MUTYH基因rs3219489位点的C等位基因可能是原发性男性不育症的保护因素，rs10527342位点可能与原发性男性不育症无关。精子DFI的增加可能会导致原发性男性不育症的患病风险增加。rs3219489、rs10527342位点可能对精子DNA完整性没有影响，且与吸烟、饮酒均无交互作用。

关键词: 不育,男（雄）性, MUTYH基因, 多态性,单核苷酸, 精子, DNA