超顺磁性纯化磁珠筛选胎儿游离DNA技术在无创产前筛查中的应用比较  

Comparison of two superparamagnetic purification magnetic beads-based screening and enrichment techniques for isolating cell-free fetal DNA from maternal plasma for non-invasive prenatal screening

作　　者：曾雯 祝建疆 戚红 蔡莉蓉 闻小慧 雒瑶 张巧 Zeng Wen;Zhu Jianjiang;Qi Hong;Cai Lirong;Wen Xiaohui;Luo Yao;Zhang Qiao(Department of Prenatal Diagnosis,Maternal and Child Health Care Hospital of Haidian District,Beijing 100080,China)

机构地区：[1]北京市海淀区妇幼保健院产前诊断科,北京100080

出　　处：《中华医学遗传学杂志》2024年第7期797-802,共6页Chinese Journal of Medical Genetics

摘　　要：目的比较2种超顺磁性纯化磁珠筛选富集胎儿游离DNA(cffDNA)的技术在无创产前检测(NIPT)中的效能,探讨改良筛选富集游离DNA(cfDNA)技术的临床应用价值。方法回顾性分析2017年12月至2022年9月在北京市海淀区妇幼保健院接受NIPT检测的26252例孕妇的资料,根据磁珠筛选cffDNA的方法将其分为常规组(10573例)和改良富集组(15679例)。对NIPT提示高风险的孕妇进行介入性产前诊断。随访所有孕妇的妊娠结局。从文库片段大小、cffDNA浓度、重复检测率和临床检验方法学评价常用指标等方面比较两种方法的检测效能。结果改良磁珠筛选富集法使游离DNA文库主峰的片段长度由常规法的294 bp减小至267 bp;cffDNA浓度由9.08%提升为21.86%(P<0.01);重复检测率由2.02%降低至0.740%(χ2=83.90,P<0.01);检测失败率由0.057%降至0.006%(P<0.05)。改良富集组在高风险及低风险人群中的复合PPV均略低于常规组(64.3%/76.1%和35.3%/45.5%),但组间无差异。常规组检测的高风险人群中出现1例21三体假阴性,改良富集组未出现假阴性。结论改良磁珠筛选富集法可显著提高cffDNA的相对浓度,降低NIPT检测的失败率及复检率,从而减少cffDNA浓度低造成的假阴性,改善了NIPT检测的整体性能。Objective To assess the efficiency of modified enrichment method for cell-free fetal DNA(cffDNA)through purified superparamagnetic beads during non-invasive prenatal testing(NIPT).Methods A total of 26252 pregnant women undergoing NIPT at the Maternal and Child Health Care Hospital of Haidian District from December 2017 to September 2022 were recruited and randomly assigned into the conventional group(n=10573)and the modified enrichment group(n=15679),who were then subjected to the screening and enrichment of the cffDNA using a conventional and modified technique,respectively.High-risk pregnant women detected by NIPT were subjected to invasive prenatal diagnosis.All women were followed up for their pregnancy outcomes,and the detection efficacy of the two methods was compared in terms of fragment size,concentration of cffDNA,duplicate detection rate,and indices of clinical laboratory tests.Results The fragment size of the main peak of the cell-free DNA library of the modified enrichment group was significantly lower than that of the conventional group[267(264,269)bp vs.294(292,296)bp,P<0.01],while the concentration of cffDNA was significantly higher[21.86%(17.61%,26.36%)vs.9.08%(6.87%,11.87%),P<0.01].In addition,the duplicate detection rate(0.740%vs.2.02%,χ2=83.90,P<0.01)and detection failure rate(0.006%vs.0.057%,P<0.05)in the modified enrichment group were significantly lower than those of the conventional group.The combined positive predictive value(PPV)in both high-risk(64.3%vs.76.1%)and low-risk(35.3%vs.45.5%)pregnant women from the modified enrichment group was slightly lower than those from the conventional group,though no significant difference was detected.There was one false negative case for trisomy 21 among the high-risk pregnant women from the conventional group,and no false negative case was found in the modified enrichment group.Conclusion The modified technique to screen and enrich the cffDNA has significantly enhanced the relative concentration of cffDNA and reduced the failure and duplication det

关 键 词：无创产前检测 cffDNA富集 胎儿浓度 假阳性 重复检测 

分 类 号：R714.5[医药卫生—妇产科学]