精子印记基因甲基化和胎停育关系的病例对照研究

A case-control study of association between methylation of sperm DNA imprinting genes and fetal stop development

目的:探讨胎停育发生的父源性表观遗传学机制。方法:选取2015年3-4月和2016年3-4月于山西省妇幼保健院生殖中心进行孕前检查的已婚男性70例作为研究对象,收集其人口学信息和精液样本,并用焦磷酸测序法检测精子印记基因H19、Peg3和Meg3甲基化水平,并以此为基线追综其生育结局。其中胎停育35例(胎停育组),根据年龄、BMI、吸烟、饮酒、受孕方式进行1:1配对选择对照组35例。用Wilcoxon符号秩和检验比较两组精子DNA印记基因H19、Peg3和Meg3甲基化水平和各CpG位点甲基化水平。结果:胎停育组与对照组精子DNA印记基因H19、Peg3和Meg3平均甲基化率没有差异(P>0.05),进一步比较各CpG位点,去掉极端值(n=4)胎停育组Meg3的甲基化率[0.0(0.0,1.7)]低于对照组[1.9(0.0,3.9)](P<0.05),而其余CpG位点两组无差异(P>0.05)。结论:精子印记基因Meg3的CpG3位点甲基化水平的降低可能增加胎停育发生风险。

Objective:To explore the paternal epigenetic mechanism of fetal stop development.Methods:During March 2015 and April 2016,a total of 702 married men who visited doctors for pre pregnancy examinations in the reproductive center of the maternal and child health care hospital of Shanxi province were selected in this study.Their demographic information and semen sample were collected.And the methylation levels of H19,Peg3 and Meg3 in sperm DNA were measured by pyrosequencing.Their newborn’s outcomes were followed up.In this study,35 subjects with fetal stop development were included in fetal stop development group,and 35 subjects were selected in the control group by 1:1 pairing based on age,BMI,smoking,drinking and conception methods.Wilcoxon test was used to compare the levels of average methylation in three imprinted genes of sperm DNA and levels of the methylation at each individual CpG site.Results:The average level of DNA methylation of imprinting gene H19,Peg3 and Meg3 in human sperm had no significantly difference between fetal stop development group and control group(P>0.05).Further comparing the difference of the level of each CpG site between two groups,the methylation levels of CpG3 and CpG6 of Meg3 in fetal stop development group were significant lower than those in control group(P<0.05),while there were no significant difference in other CpG sites between the two groups(P>0.05).Conclusion:The decreasing of methylation level of Meg3 in sperm DNA may increase the risk of fetal stop development.