【摘要】 目的　建立可靠有效的检测孕妇血浆胎儿DNA的方法 ,探讨其在非创伤性产前诊断中的价值。方法　采用引物延伸预扩增 (PEP)法及巢式PCR技术对 65例孕妇外周血血浆DNA进行正常男性SRY基因检测。结果　单用巢式PCR技术和联合应用PEP、PCR技术对怀男胎的孕妇血中SRY基因检出率分别为 65 .2 % ( 3 0 / 4 6)和 89.1% ( 4 1/ 4 6) ,两组差异有极显著性。对怀女胎孕妇血中SRY基因的未检出率为 78.9% ( 15 / 19)和 94 .7% ( 18/ 19) ,两组差异无显著性。结论　应用PEP法可对胎儿DNA进行全基因组扩增使DNA模板量增加 ,并使继后的PCR技术检测SRY基因的敏感性明显提高。PEP法是解决母血中胎儿细胞数量太少的途径之一。孕妇血浆中胎儿DNA可成为非创伤性产前诊断的胎儿物质来源。更多还原

【Abstract】 Objective To establish a reliable and effective method for detecting fetal DNA in maternal plasma and to explore its value in non-invasive prenatal diagnosis.Methods Using primer extension preamplification (PEP) and nested polymerase chain reaction (PCR), a normal male SRY gene in maternal plasma DNA was detected in 65 gravidas.Results The detectable rate of the SRY gene in maternal plasma DNA from women carrying male fetuses was 65.2% (30/46) by nested PCR and 89.1% (41/46) by PCR and PEP respectively (P< 0.01).The non-detectable rate of SRY gene in maternal plasma DNA from women carrying female fetuses was 78.9% (15/19) by nested PCR and 94.7% (18/19) by PCR and PER (P> 0.05).Conclusion PEP can amplify the amount of whole genome of fetal DNA and increase the amount of DNA template.PEP is one of the methods to solve the lower number of fetal cells from maternal blood.Fetal DNA in maternal plasma can be used in noninvasive prenatal diagnosis.更多还原