柳州地区21047例无创产前检测结果回顾性研究

目的 探讨孕妇外周血胎儿游离DNA无创产前检测(non-invasive prenatal testing,NIPT)在柳州地区胎儿染色体非整倍体产前筛查的应用价值.方法 对2016年8月-2019年3月柳州地区21047例孕妇外周血样本行无创产前检测,对筛查高风险的孕妇行有创产前诊断,并进行妊娠结局随访.结果 NIP...     

胎儿游离DNA检测染色体非整倍体1071例临床应用

目的利用高通量测序技术检测孕妇外周血浆中游离DNA行胎儿非整倍体的临床实践研究。方法选择2012年9月至2013年9月在温州市中心医院产(温州市产前诊断中心)就诊,年龄在19-45岁之间,孕龄在12+0-35+6w之间,有产前诊断指征,拒绝有创产前诊断,但同意介入本研究的单胎孕妇1071例,抽取外周静脉血10ml,利用高通量测序技术进行DNA测序,测序结果提示异常者,行有创产前诊断核型分析;正常者随访至出生。分析参与研究的人群,评价无创DNA检测技术检出率和可行性。结果 1.参加无创DNA检测人群分析:试管婴儿占37.16%,单纯精神因素惧怕介入产前诊断风险者占23.90%,疤痕子宫占12.05%,妊娠合并乙肝占11.67%,先兆流产占7.38%,妊娠合并子宫肌瘤4占3.92%,胎盘低置状态占2.24%,妊娠合并梅毒占1.68%。2.无创DNA检测技术1071例孕妇筛查检出率分析:受检者共检测出14例异常者,检出率1.31%,与核型分析相符。余1057例检测提示正常者均随访至胎儿出生,1057例随访未发现新生儿异常。结论利用高通量测序技术检测胎儿非整倍体,为惧怕或无法行有创产前诊断者开辟了新途径,是创伤性产前诊断的良好补充,具有临床应用价值。     

无创产前基因检测在胎儿非整倍体筛查中的应用

目的探讨无创产前基因检测技术在胎儿染色体非整倍体筛查中的应用价值。方法选择在医院行无创产前基因检测的单胎孕妇450例,对孕妇外周血中游离DNA进行高通量测序,对检测结果高风险者进行羊膜腔穿刺或脐静脉血穿刺行胎儿染色体核型分析,对检测结果低风险者行电话随访。结果 450例孕妇中,无创产前基因检测高风险9例。高风险孕妇均行介入性产前诊断,确诊唐氏综合症5例,18三体综合症2例,性染色体异常1例(47,XXX),染色体核型正常1例。低风险孕妇追踪随访未发现唐氏儿漏诊。其灵敏度为100%,特异度为99.77%,假阳性率0.23%,阳性预测值为88.89%,阴性预测值100%,Youden指数为0.9977。结论无创产前基因检测技术具有高灵敏性,低假阳性,对降低出生缺陷率是有效的,值得在临床上推广应用。     

宜昌地区8526例无创产前胎儿染色体非整倍体基因检测结果分析

目的探讨无创产前胎儿染色体非整倍体基因检测技术(non-invasive?fetal?trisomy?test,NIFTY)在产前筛查和产前诊断临床应用中的适用性和准确率,同时探索适宜的孕妇产前筛查和产前诊断流程。方法应用高通量测序技术对8526份孕妇外周血浆进行胎儿游离DNA检测分析,将孕妇分为高龄组,产前血清学筛查高风险组、产前血清学筛查临界风险组、胎儿超声异常组和首选无创组,对胎儿染色体非整倍体检测结果高风险的孕妇建议进行介入性产前诊断,行羊膜腔穿刺及胎儿染色体核型分析,对低风险结果进行随访。结果 8526例孕妇共有74例检测结果高风险,检出率0.87%,其中产前血清学筛查高风险组的检出率最高,达2.01%。最终有54例孕妇接受介入性产前诊断,确诊胎儿染色体异常39例,阳性预测值72.22%,在确诊胎儿染色体异常的39例中,21-三体19例,阳性预测值95.00%;18-三体10例,阳性预测值90.91%;13-三体2例,阳性预测值50.00%,性染色体异常8例,阳性预测值61.54%。结论 NIFTY是一种高效、高准确性和非侵入性的胎儿染色体非整倍体产前筛查技术,特别是对21-三体和18-三体有较高的临床应用价值,可作为传统产前诊断技术的有效辅助手段。但存在一定假阳性率,必须通过胎儿染色体核型加以验证。     

无创性产前基因检测技术在未行血清学筛查的高龄孕妇中的应用

目的探讨应用无创性产前基因检测技术对孕妇血浆胎儿游离DNA进行染色体拷贝数检测的可行性。方法选择2011年10月至2015年8月于佛山市妇幼保健院行无创性产前基因检测的730例高龄孕妇(年龄≥35岁),孕周:12-24周,年龄:35-41岁,均为单胎。对无创性产前基因检测结果阳性的孕妇行羊膜腔穿刺或脐静脉血穿刺,行常规染色体核型分析和/或基因芯片检测。对所有高龄孕妇行电话随访,统计分析无创性产前基因检测的准确性。结果 730例孕妇中,母体血浆胎儿游离DNA产前基因检测技术发现21例胎儿染色体拷贝数异常者。其中15例通过羊膜腔穿刺或脐静脉血穿刺行有创性产前诊断,检出21三体7例,45,X[7]/46,i(X)(q10)[23]和45X[13]/46,XX[37]各1例,47,XXX1例,13号染色体微缺失1例,无一例假阴性。无创性非整倍体检测对常见染色体非整倍体的检出率100%,灵敏度100%,特异度99.43%,假阳性率0.57%,假阴性率为0,阳性预测值73.33%。结论无创性产前基因检测技术用于高龄孕妇检测胎儿染色体拷贝数异常具有高度敏感性和特异性优点,假阳性率很低,在对高龄孕妇的胎儿染色体拷贝数变异的产前检测中具有广泛的应用前景。     

无创DNA检测技术在产前筛查中的临床应用

目的 探讨无创DNA基因检测技术应用于产前筛查中的临床价值及意义。方法 回顾性分析在我院2015年1月~2017年1月针对553例孕妇包括预产期年龄≥35岁的高龄产妇、唐筛结果为高风险、临界风险或单项指标异常、超声软指标等孕妇。在充分知情同意,进行遗传咨询后选择胎儿无创DNA产前检测,对检测结果为高风险孕妇进一步进行染色体核型分析,对低风险孕妇进行电话追踪随访。结果 553例孕妇外周血中,541例低风险,12例高风险,在高风险病例中7例提示21三体异常;2例提示18号染色体异常;1例提示13三体异常;2例提示胎儿性染色体异常;无创DNA检测结果为高风险的12例孕妇,均进行了羊水或脐血穿刺,7例21三体高风险中7例为47,XN,+21;2例18三体高风险者中1例为47,XN,+18,1例为46,XN;1例13三体高风险者中1例为47,XN,+13;2例性染色体异常中,1例为XXY,1例为45X。并对无创DNA检测阴性的出生新生儿进行随访,未诉明显异常。应用无创DNA检测技术诊断胎儿染色体疾病的敏感度为100.00%,特异度为99.91%,假阴性率为0,假阴性率为0.09%,无创DNA产前检测对21三体,13三体和性染色体的符合率为100.00%,对18三体的符合率为50.00%。结论 无创DNA检测技术在产前筛查中准确性高,假阳性和假阴性低的优点,可提高产前筛查效率,减少染色体疾病患儿的出生,是快捷、安全、较介入性产前诊断易于接受、值得推广的安全可靠的产前筛查方法,是今后发展的必然趋势。但无创DNA检测出的高风险孕妇,也必须进行羊水穿刺进一步确诊。     

无创DNA检测在产前诊断中的应用

目的探讨无创DNA产前检测在胎儿染色体异常疾病筛查中的应用及意义。方法收集2016年1月1日至2017年6月30日在我院接受孕妇外周血中游离胎儿DNA检测者共2788例,对无创DNA提示阳性者劝说接受进一步羊水/脐血细胞核型分析,阴性者进行电话跟踪和出生后随访。结果 2788例患者中无创提示阳性37例,包含17例21-三体,3例18三体,14例性染色体异常,其他染色体异常3例,分别是1例Chr13-/Multi,1例4号染色体q12-q13.1处重复4.6Mb,1例13-染色体单体或部分缺失。其中28例接受进一步产前诊断,确诊10例21-三体,3例18三体,6例性染色体异常。结论无创DNA检测对21-三体准确率达到83.33%,对18-三体检测准确率达到100%,性染色体检测准确率达到50%。无创DNA检测对胎儿的非整倍体疾病检出率比较高,对性染色体和其他染色体异常的检出率还有待进一步提高。     

无创产前检测在胎儿性染色体检测中的应用价值

目的探讨以母体外周血游离DNA进行大规模平行基因测序技术用于胎儿性染色体无创产前基因检测的可行性。方法选择在充分知情同意下自愿参加无创产前基因检测的满12周的孕妇作为研究对象,抽取静脉外周血10m L,提取游离胎儿DNA,在高通量测序仪上测序,通过比对数据库判断为性染色体异常的给予遗传咨询,在知情选择下行羊水穿刺作核型分析。结果本院2015年4月至2017年9月,共有13 505位孕妇行无创产前基因检测,无创产前基因检测结果显示91位(0.67%)孕妇为性染色体异常,包括Chr X-:43例;Chr X-(Y):6例,Chr X+:16例,Chr X+(Y):19例,Chr Y+:7例。87例接受随访,66例接受产前诊断,40例核型结果与无创产前检测结果一致。胎儿性染色体的无创产前基因检测的总体阳性预测值为60.6%(40/66)。结论无创产前基因检测(NIPT)技术可用于性染色体异常的检测,但阳性预测值有待进一步提高。     

无创产前检测和FISH技术的临床应用

目的探讨无创产前检测和FISH技术在胎儿染色体非整倍体检测中的临床应用价值。方法选择2016年10月-2017年10月自愿参与NIPT检测孕妇4807例,对NIPT检测结果高风险孕妇行羊膜腔穿刺术,应用染色体核型分析和FISH分析对NIPT结果进行验证,对NIPT检测结果低风险者进行常规随访。结果 4787例孕妇共检出65例(1.34%)染色体数目异常高风险胎儿,包括1例13-三体、8例18-三体、18例21-三体,38例性染色体异常。59例孕妇接受进一步的羊膜腔穿刺术及产前诊断,穿刺率为1.23%(60/4787)。介入性产前诊断确诊1例13-三体、6例18-三体、16例21-三体和13例性染色体异常胎儿,阳性预测值分别是:100%、85.7%、88.9%和39.4%。NIPT检测结果提示2例21-三体嵌合体和1例18-三体嵌合体,利用FISH技术检测均证实为低比例嵌合体。其中345例唐氏筛查高风险孕妇,NIPT检测出6例高风险孕妇经产前诊断确诊,其余为低风险孕妇通过常规随访得到验证。结论无创产前基因检测在胎儿染色体非整倍体疾病检测中具有很高的灵敏度、特异性,联合FISH技术可以快速准确确诊染色体非整倍体,值得临床应用推广,降低先天性缺陷儿出生率。     

无创产前DNA检测胎儿染色体非整倍的临床应用分析

目的探讨无创产前DNA检测技术在产前诊断中的应用价值。方法针对2012年1月~2015年2月在内蒙古妇幼保健院产前诊断中心就诊的1115例孕妇,采集孕妇外周静脉血,提取血浆DNA,制备测序文库,应用Ion Proton半导体测序平台得的基因序列,并与人类的参考基因组比对,进行统计分析。对检测结果为高风险者行羊水穿刺,以羊水或脐血核型分析作为实验对照以及检测标准;对检测结果为低风险的孕妇随访妊娠结局。结果 1115例样本中,提示胎儿高风险有14例,其中21-三体高风险3例,18三体高风险4例,13三体高风险2例,性染色体异常2例,低风险为1101例;高风险孕妇行羊水或脐血穿刺及染色体核型分析,以其为金标准进行结果对照,结果显示存在2例13-三体高风险患者为假阳性,1例X染色体高风险患者,其羊水细胞核型分析结果为47,XYY;其余11例染色体核型分析结果均与无创产前DNA检测的结果相符。对检查结果为低风险的孕妇进行产后随访,无漏诊病例。胎儿游离DNA高通量基因测序技术的敏感度为100%(12/12),特异度为99.82%(1103/1105)。结论应用无创产前DNA检测技术对孕妇血浆游离DNA进行胎儿染色体非整倍体检测,具有无创、快速、敏感度高、特异度高等优势,具有重要的临床应用价值。     

Non-invasive exclusion of fetal aneuploidy in an at-risk couple with a balanced translocation

A pregnant woman who was a carrier for a balanced chromosome translocation [46,XX, t(1;6) (p31;q14)] and who had had six miscarriages, declined invasive testing but agreed to non-invasive prenatal diagnosis by analysis of fetal cells in maternal blood. Monoclonal antibody (Mab) against the zeta (z) and gamma (gamma) chains of embryonic and fetal haemoglobin were used to identify fetal nucleated erythrocytes (FNRBC). There were no FNRBC detected at 7 weeks, one anti-z-positive FNRBC was detected at 11 weeks, and 12 anti-gamma-positive FNRBC were detected at 20 weeks. Fluorescent in-situ hybridization was performed using probes for chromosomes X, Y, 1 and 6 to identify fetal gender and the presence of an unbalanced chromosomal translocation. A tentative prenatal diagnosis was made of a female fetus disomic for chromosomes 1 and 6. A female infant with a 46,XX karyotype was born at term. This is the first attempt of exclusion of a chromosome translocation using fetal cells isolated from maternal blood. There is an advantage of using fetal cells isolated from maternal blood for non-invasive prenatal diagnosis in couples who have a history of multiple miscarriages due to a parental translocation, and who decline invasive testing in a pregnancy that continues to the second trimester.     

Noninvasive whole-genome sequencing of a human fetus

Analysis of cell-free fetal DNA in maternal plasma holds promise for the development of noninvasive prenatal genetic diagnostics. Previous studies have been restricted to detection of fetal trisomies, to specific paternally inherited mutations, or to genotyping common polymorphisms using material obtained invasively, for example, through chorionic villus sampling. Here, we combine genome sequencing of two parents, genome-wide maternal haplotyping, and deep sequencing of maternal plasma DNA to noninvasively determine the genome sequence of a human fetus at 18.5 weeks of gestation. Inheritance was predicted at 2.8 × 10(6) parental heterozygous sites with 98.1% accuracy. Furthermore, 39 of 44 de novo point mutations in the fetal genome were detected, albeit with limited specificity. Subsampling these data and analyzing a second family trio by the same approach indicate that parental haplotype blocks of ~300 kilo-base pairs combined with shallow sequencing of maternal plasma DNA is sufficient to substantially determine the inherited complement of a fetal genome. However, ultradeep sequencing of maternal plasma DNA is necessary for the practical detection of fetal de novo mutations genome-wide. Although technical and analytical challenges remain, we anticipate that noninvasive analysis of inherited variation and de novo mutations in fetal genomes will facilitate prenatal diagnosis of both recessive and dominant Mendelian disorders.     

Fetal cells in the maternal circulation: isolation by multiparameter flow cytometry and confirmation by polymerase chain reaction.

During pregnancy, nucleated fetal erythrocytes enter the maternal circulation and can be isolated efficiently from the maternal cells by multiparameter flow cytometry. Male DNA, implying presence of a male fetus, can be identified in flow-sorted maternal blood by polymerase chain reaction with oligonucleotide primers flanking single-copy Y-specific DNA sequences. Among flow-sorted samples, we correctly identified fetal sex in 17/18 (94%) pregnancies of 10-21 weeks gestation. Maternal blood thus provides a potential opportunity for prenatal diagnosis that could preclude the need for invasive procedures in current use.     

Recognition of Smith-Lemli-Opitz syndrome (RSH) in the fetus: utility of ultrasonography and biochemical analysis in pregnancies with low maternal serum estriol

Smith-Lemli-Opitz syndrome (SLOS), or RSH, is an autosomal recessive disorder caused by mutations of the gene encoding 7-dehydrocholesterol reductase (DHCR7). The utility of maternal serum screens and ultrasound as prenatal screening methods for SLOS is presently undetermined. We report the clinical, cytogenetic, biochemical, and molecular findings of a stillborn with SLOS. The diagnosis was made postnatally on the basis of physical findings and confirmed by biochemical and DNA analyses of fetal tissue. Although abnormalities were detected by maternal serum triple screen and prenatal ultrasonography, a diagnosis of SLOS was not suspected before delivery. This study demonstrates that patients with SLOS may escape prenatal diagnosis despite the presence of multiple anomalies and abnormal maternal serum screen results, and lends support for consideration of prenatal biochemical testing for SLOS in pregnancies with these findings. As SLOS is a severe autosomal recessive disorder with a recurrence risk of 25%, ultrasonographic, cytogenetic, and biochemical analyses in the second trimester should be considered if abnormal maternal serum screening results, specifically low levels of unconjugated estriol, are detected.     

Recent developments in fetal nucleic acids in maternal plasma: implications to noninvasive prenatal fetal blood group genotyping.

The discovery of circulating cell-free fetal DNA in maternal plasma has opened up new possibilities for noninvasive prenatal diagnosis. Fetal DNA in maternal plasma has been used for the noninvasive prenatal determination of the RhD status of fetuses carried by RhD-negative pregnant women. In such analysis, the possible need of an internal control for the presence of detectable amounts of fetal DNA in a particular maternal plasma sample has been actively discussed. Recently, the development of a robust method for discriminating single nucleotide differences in plasma DNA using single allele base extension reaction (SABER) followed by matrix-assisted laser-desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS) has opened up the possibilities of using a panel of single nucleotide polymorphisms as such a positive control. A second approach is the recent successful development of fetal epigenetic markers which can be developed into universal fetal DNA markers. These developments hold promise to allow the eventual widespread utilization of maternal plasma DNA analysis for the noninvasive prenatal diagnosis of blood group mismatches between the mother and fetus.     

石家庄地区无创胎儿染色体非整倍体产前DNA测序临床研究

目的探讨无创胎儿染色体非整倍体产前DNA测序临床应用价值。方法采用孕妇外周血生化筛查,高危孕妇进行无创高通量DNA检测,阳性的孕妇采取羊水进行诊断。结果963例高危孕妇无创筛查发现阳性病例13例,其中98．65％孕妇避免了羊膜腔穿刺。结论）胎儿基因检测是采用孕妇血液检测,对胎儿没有创伤并可在孕早期做出诊断,是传统筛查和诊断方法的补充。     

Prenatal diagnosis and 47,XXY

In this contribution, we consider detection of 47,XXY by a variety of available methods. These include traditional invasive procedures, screening with maternal serum analytes and fetal ultrasound, and most recently cell-free fetal DNA. Since its introduction in the late 1960s, prenatal genetic diagnosis has evolved greatly. Serendipitious detection of 47,XXY was not infrequent when prenatal genetic diagnosis routinely involved testing by the invasive procedures CVS and amniocentesis. In 2013 this is much less common and relatively few pregnancies in the U.S. and Europe are tested without prior screening protocols, traditionally maternal serum analyte and fetal ultrasound (NT). These protocols are not designed to identify 47,XXY or other X-chromosome aneuploides and with screening by analysis of cell-free DNA in maternal blood, this situation may or may not be altered. Increased numbers of cases could be detected if intake increases and vendors offer information on 47,XXY. A further consideration is that ability of array CGH to detect microdeletions or microduplications below resolution of a karyotype could make return to direct testing using an invasive procedure attractive. © 2013 Wiley Periodicals, Inc.     

Comparison of next generation sequencing-based and methylated DNA immunoprecipitation-based approaches for fetal aneuploidy non-invasive prenatal testing

Over the past few years, many researchers have attempted to develop non-invasive prenatal testing methods in order to investigate the genetic status of the fetus. The aim is to avoid invasive procedures such as chorionic villus and amniotic fluid sampling, which result in a significant risk for pregnancy loss. The discovery of cell free fetal DNA circulating in the maternal blood has great potential for the development of non-invasive prenatal testing (NIPT) methodologies. Such strategies have been successfully applied for the determination of the fetal rhesus status and inherited monogenic disease but the field of fetal aneuploidy investigation seems to be more challenging. The main reason for this is that the maternal cell free DNA in the mother’s plasma is far more abundant, and because it is identical to half of the corresponding fetal DNA. Approaches developed are mainly based on next generation sequencing (NGS) technologies and epigenetic genetic modifications, such as fetal-maternal DNA differential methylation. At present, genetic services for non-invasive fetal aneuploidy detection are offered using NGS-based approaches but, for reasons that are presented herein, they still serve as screening tests which are not readily accessed by the majority of couples. Here we discuss the limitations of both strategies for NIPT and the future potential of the methods developed.     

Fetal cells in transcervical samples at an early stage of gestation

Several investigations are in progress with the aim of performing prenatal diagnosis of inherited disorders by noninvasive or minimally invasive techniques. The most important approaches are based on the detection of fetal nucleated cells in maternal blood, the analysis of fetal DNA present in maternal plasma, and the identification and isolation of fetal trophoblastic cellular elements shed into the uterine cavity and the endocervical canal. In this review, we discuss the methods that have been employed for the collection of the transcervical samples at an early stage of gestation and the techniques used for the identification of fetal cells. We also report the results of using endocervical cells for the detection of fetal chromosomal disorders by fluorescent in-situ hybridization and for performing prenatal diagnosis of fetal Rh(D) phenotypes. Recent investigations have also shown that — after the isolation of trophoblastic cells from maternal contaminants by micromanipulation — transcervical samples can be employed for the prenatal diagnosis of single gene defects, such as those causing thalassemia and sickle cell anemia. Although the present results are promising, further investigations are required to demonstrate the feasibility of performing accurate diagnosis of fetal diseases by this minimally invasive approach in all transcervical samples retrieved at an early stage of gestation. Received: November 7, 2000 / Accepted: November 27, 2000     

Investigation of maternal blood enriched for fetal cells: role in screening and diagnosis of fetal trisomies.

Prenatal diagnosis of chromosomal abnormalities relies on assessment of risk followed by invasive testing in the group with highest risk. Assessment of risk by a combination of maternal age and fetal nuchal translucency and invasive testing in the 5% of the population with the highest risk would identify about 80% of trisomy 21 pregnancies. Preliminary reports suggest that chromosomal abnormalities can also be diagnosed by fluorescent in situ hybridization (FISH) in maternal blood enriched for fetal cells. This study examines the potential role of this method on the prenatal diagnosis of fetal trisomies. Maternal blood was obtained before invasive testing in 230 pregnancies at 10-14 weeks of gestation. After enrichment for fetal cells, by triple density centrifugation and anti-CD71 magnetic cell sorting, FISH was performed and the proportion of cells with positive signals in the chromosomally normal and abnormal groups was determined. Fetal karyotype was normal in 150 cases and abnormal in 80 cases, including 36 with trisomy 21. Using a 21 chromosome-specific probe, three-signal nuclei were present in at least 5% of the enriched cells from 61% of the trisomy 21 pregnancies and in none of the normal pregnancies. For a cut-off of 3% of three-signal nuclei the sensitivity for trisomy 21 was 97% for a false positive rate of 13%. Similar values were obtained in trisomies 18 and 13 using the appropriate chromosome-specific probe. Examination of fetal cells from maternal blood may provide a noninvasive prenatal diagnostic test for trisomy 21 with the potential of identifying about 60% of affected pregnancies. Alternatively, this technique can be combined with maternal age and fetal nuchal translucency as a method of selecting the high-risk group for invasive testing. Potentially, 80% of trisomy 21 pregnancies could be identified after invasive testing in less than 1% of the pregnant population.