短片段胎儿DNA富集技术可提高无创产前筛查的准确性  

The short fragment fetal cell-free DNA enrichment techniques can improving the accuracy of non-invasive prenatal testing

作　　者：吴小娟 贺权泽 张春花 王挺[1] WU Xiaojuan;HE Quanze;ZHANG Chunhua;WANG Ting(Reproductive and Genetic Center of Suzhou Municipal Hospital,Suzhou,Jiangsu 215000,China)

机构地区：[1]苏州市立医院生殖与遗传中心,江苏苏州215000

出　　处：《中国优生与遗传杂志》2024年第4期828-832,共5页Chinese Journal of Birth Health & Heredity

摘　　要：目的探讨孕妇外周血中短片段胎儿DNA富集技术对降低无创产前筛查(NIPT)技术中假阳性和假阴性的可行性。方法选取NIPT结果高风险而羊水穿刺核型分析正常(假阳性)以及NIPT结果低风险而羊水穿刺核型分析异常(假阴性)样本为研究对象。将假阳性和假阴性样本重建库后,通过E-GEL胶对短片段胎儿DNA进行富集后再测序分析,与常规NIPT结果进行对比分析。结果常规NIPT假阳性结果Z值主要分布在3≤Z值<6区间,在此区间21-三体、18-三体和13-三体的阳性预测值仅为22.58%、23.53%和21.43%。68例假阳性样本经短片段胎儿DNA富集后重新测序,胎儿游离DNA浓度由10.3%提高到28.7%,43例(63.24%)NIPT高风险结果转为低风险,阳性预测值分别提升至43.75%、44.44%和26.09%。4例假阴性样本经短片段胎儿DNA富集后,3例(75.00%)被正确检出。结论对Z值落在3≤Z值<6的筛查高风险样本利用短片段胎儿DNA富集技术进行二次检测,能够提高21-三体、18-三体和13-三体的阳性预测值,降低当前NIPT的假阳性率。同时富集技术能提高胎儿DNA浓度,降低假阴性率。Objective To evaluate the feasibility of short fragment fetal cell-free DNA enrichment techniques in maternal peripheral blood for non-invasive prenatal testing to reduce the false positive rate and false negative rate of traditional NIPT.Methods In this study,68 false positive cases and 4 false negative cases were retrospectively analyzed by E-GEL based size-selection NIPT.The NIPT results were compared with those of traditional NIPT.Results The Z value of traditional NIPT false positive results were mainly distributed in 3≤Z<6,in which the positive predictive value of trisomy 21,trisomy 18 and trisomy 13 were only 22.58%,23.53% and 21.43%.Of the 68 false positive cases retested by E-GEL based size-selection NIPT,43(63.24%)had negative results,the fetal cfDNA fraction increased from 10.3% to 28.7%,and the positive predictive value of trisomy 21,trisomy 18 and trisomy 13 increased to 43.75%,44.44% and 26.09%,respectively.Of four false negative retested cases,3(75.00%)had positive size-selection NIPT results.Conclusion For the positive samples whose Z value distributed in 3≤Z value<6,retseting by size-selection NIPT can improve the positive predictive value of trisomy 21,trisomy 18 and trisomy 13,and reduce the false positive rate of NIPT.Size-selection NIPT can increase the fetal cfDNA fraction,reduce the false positive rate of traditional NIPT.

关 键 词：无创产前筛查 胎儿游离DNA 富集 假阳性 

分 类 号：R714.5[医药卫生—妇产科学]