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。     

Reproductive behaviour following spontaneous loss of a pregnancy after prenatal diagnosis

One hundred and fifty-eight women of advanced maternal age with complete follow up who experienced spontaneous fetal loss after prenatal diagnosis were studied for reproductive behaviour as well as prenatal diagnosis in a subsequent pregnancy. A higher rate of subsequent pregnancies amongst women who experienced an early spontaneous abortion after chorionic villus sampling (CVS) was expected compared with women who lost a pregnancy later during pregnancy after amniocentesis. Of the 92 women who underwent CVS in a previous pregnancy, 57 (62%) became pregnant again. Of the 66 women who underwent amniocentesis in the pregnancy that ended in fetal loss, 34 women (52%) had a subsequent pregnancy. The cumulative incidence of subsequent pregnancies was significantly influenced by maternal age but not by parity or the method of prenatal testing. Most women who decided on a new pregnancy opted for prenatal diagnosis. There was a preference for amniocentesis if the patient had previously undergone CVS. However, the reverse was not the case.     

Clinical application of fetal sex determination using cell-free fetal DNA in pregnant carriers of X-linked genetic disorders

As the first step in prenatal diagnosis of X-linked genetic disorders, chorionic villus sampling (CVS) for fetal sex determination is generally performed at 11-13 weeks of gestation. However, as the procedure-related miscarriage rate of CVS is 0.5-1.0%, non-invasive methods such as PCR of cell-free fetal DNA (cff-DNA) in maternal plasma are preferable. Here, we determined fetal sex at 9-12 weeks of gestation using PCR of cff-DNA in three pregnant carriers of Duchenne muscular dystrophy. The fetal sex was accurately determined in all three cases, as confirmed by ultrasound and amniocentesis at 16 weeks (for the two female fetuses) and CVS at 12 weeks (for the one male fetus). This procedure could avoid unnecessary CVS in female fetuses.     

Prenatal cystic fibrosis screening in a low-risk population undergoing chorionic villus sampling for fetal karyotyping

Screening for cystic fibrosis (CF) has been offered to pregnant women seeking chorionic villus sampling (CVS) for prenatal chromosomal abnormality investigation. The mutation panel has increased over the years to include 8 mutations and can detect 65% of abnormal CF genes in the Italian population. Testing was offered to a total of 2214 consecutive pregnant women; 45 of them declined screening (take up rate: 98%). In 1055 of the 2169 pregnancies screened, the test was at first done on the fetus, while in the remaining cases both parents were investigated. Among parents 46 carriers were identified (2.1%), in 41 of whom the mutation was delta F508. In two couples both parents were heterozygous, and in one the fetus was affected and the pregnancy was terminated. Although CF testing offered to pregnant women undergoing invasive investigation such as CVS may not be the model for a mass screening, its very high effectiveness can represent an advantageous component of more comprehensive strategies.     

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.     

唐氏综合征的产前筛查和产前诊断

目的通过研究唐氏综合征胎儿的临床特点,探讨唐氏综合征的产前筛查和产前诊断方法。方法回顾性分析我院产科4年来42例经染色体诊断为唐氏综合征的病例临床资料。结果42例孕妇其中高龄产妇20例,单纯因高龄行染色体检查12例,超声诊断畸形3例,超声异常5例。年龄小于35岁22例,其中唐氏征筛查高危8例,超声异常2例,畸形10例,超声异常伴有唐氏征筛查高危1例,1例孕期无异常发现,分娩后证实。40例患者中6例继续妊娠者,1例拒绝随访,1例发生胎死宫内,3例存活并发生胎儿宫内发育受限,1例臀位分娩生后证实。结论高龄孕妇进行染色体检查是必要的,超声检查对于唐氏综合征的筛查具有重要的指导意义,NT增厚的患者积极建议进行产前诊断。对于胎儿可治疗的畸形要求继续妊娠者需要积极除外染色体疾病的风险。对于临床晚期出现的宫内发育受限的患者亦要高度警惕发生染色体异常的风险。     

Update on the prevention,diagnosis and management of cytomegalovirus infection during pregnancy

Human cytomegalovirus (CMV) is the leading cause of congenital infection, with morbidity and mortality at birth and sequelae. Each year approximately 1–7% (Rev Med Virol 2010; 20: 311) of pregnant women acquire a primary CMV infection. Of these, about 30–40% transmit infection to their fetuses. The risk of serious fetal injury is greatest when maternal infection develops in the first trimester or early in the second trimester. Between 10 and 15% of congenitally infected infants are acutely symptomatic at birth and most of the survivors have serious long-term complications. Until a few years ago, laboratory testing was not possible to precisely define the maternal immune status, the recent development of advanced serological tests (IgG avidity test, IgM immunoblot and neutralizing antibody testing) allow us to identify, among pregnant women with suspected CMV, those with primary infection who are therefore at high risk of transmitting CMV to the fetus. This is done with the use of a screening test. As most maternal infections are asymptomatic, the only way to disclose primary infection is to implement specific serological testing as early in pregnancy as possible (before week 12–16 of gestation). Given the high risk of mother–fetus transmission and fetal damage, prenatal diagnosis is recommended to women with primary CMV infection contracted in the first half of pregnancy and in case of fetal abnormalities suggestive of infection. The correct interpretation of serological and virological tests followed by appropriate counselling by an expert physician is an effective tool to reduce the number of unnecessary pregnancy terminations by over 70% (Am J Obstet Gynecol 2007; 196: 221.e1).     

产前超声诊断胎儿肢体畸形的技术探讨

目的　探讨通过产前超声提高胎儿肢体畸形诊断率的操作技巧。 方法　采用连续顺序追踪法对2014年1月至2015年1月142,17例孕16～37周孕妇常规行胎儿肢体超声成像。 结果　全部胎儿中发现肢体畸形41例,检出率为0.28%,其中包括肢体大部分缺失1例,肢体部分缺失4例,桡骨缺失6例,马蹄内翻足9 例,裂手畸形2例,腓骨缺失2例,多指（趾）2例,羊膜束带综合征2例,手姿势异常4例,先天性多发性关节挛缩2例,并腿畸形3例,严重短肢畸形4例。漏诊16例,占所有畸形的28%,包括7例并指畸形,5例多指（趾）畸形,4例重叠指,误诊2例马蹄内翻足,均经引产或出生后证实。 结论　产前超声能直观显示胎儿肢体结构,是诊断胎儿肢体畸形的首选方法,熟练的操作技术及操作技巧是产前超声诊断胎儿肢体畸形的关键。     

Diagnostic techniques: Rapid genetic diagnosis at 7-9 weeks gestation: diagnosis of sex, single gene defects and DNA fingerprint from coelomic samples

Prenatal diagnosis (chorionic villus sampling (CVS) or amniocentesis)is performed at a relatively late stage of pregnancy (11–18weeks). Such tests have significant disadvantages includingincreased risk of miscarriage and delay before results are known.Earlier prenatal diagnosis (<11 weeks) has been discontinuedbecause of the risk of fetal abnormalities. Recently fetal cellshave been recovered from the coelomic cavity at 7–12 weeksgestation (coelocent-esis). This study has established thathighly sensitive fluorescent polymerase chain reaction (PCR)can provide rapid (4–5 h), reliable and accurate multiplegenetic diagnoses (sexing and single-gene diagnosis) from coelomiccells. As prenatal diagnosis has a significant risk of contamination,we have also shown that coelomic cells can be simultaneouslyDNA fingerprinted to determine that contamination has not occurred.This earlier method of prenatal diagnosis would be very valuable,as it may overcome some problems of later conventional prenataldiagnosis and allow reassurance/treatment to be undertaken ata much earlier stage. Successful application of these techniquesmay supersede alternative methods of prenatal diagnosis. Althoughthese techniques appear very promising, extensive clinical trialsmust be undertaken to determine safety of coelocentesis, diagnosticreliability and accuracy in a clinical setting.     

基于游离DNA单分子标签检测技术的眼皮肤白化病Ⅰ型的无创产前检测

目的探讨基于游离DNA单分子标签检测技术(cfDNA barcode-enabled single-molecule test,cfBEST)的无创产前检测方法对于眼皮肤白化病Ⅰ型产前诊断的价值。方法采用cfBEST方法为1个眼皮肤白化病Ⅰ型家系提供无创产前检测,之后通过羊膜腔穿刺产前诊断进行验证,并随访妊娠的结局。结果cfBEST的无创产前检测结果显示,胎儿游离DNA浓度为6.6%,眼皮肤白化病Ⅰ型相关的TYR基因c.929_930insC(p.Arg311Lysfs*7)变异占比为45.7%,c.1037-7T>A变异占比为0%,且2个变异未检出的后验概率均为1,提示胎儿未携带这两个变异。经羊膜腔穿刺产前诊断验证,结果一致,随访提示胎儿正常。结论基于cfBEST技术的无创产前检测方法可用于检测血浆游离DNA中的母婴基因型组合,具有临床可行性。     

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.     

超声在出生缺陷产前诊断中的临床应用

目的 探讨超声在产前诊断胎儿缺陷的临床价值。方法 对4927例孕16～40周的妇女采用实时彩色多普勒超声仪进行系统检查，对胎儿畸形进行筛查和诊断。结果 在4927例孕妇中，共发现先天性缺陷58例，产前共诊断出48例胎儿畸形，漏诊10例。漏诊病例主要表现为较小畸形和缺陷。结论 妊娠中晚期进行系统超声检查可以对胎儿形态结构方面的明显畸形进行产前诊断，对于降低出生缺陷发生率，提高人口素质具有重要意义。     

染色体微阵列分析技术在高龄孕妇产前诊断中的应用价值

目的:探讨染色体微阵列分析(chromosomal microarray analysis,CMA)对于高龄孕妇异常妊娠的检测价值。方法:回顾分析562例高龄孕妇的CMA检测结果、妊娠结局及新生儿的随访结果。结果:在562份羊水样本中,共检出胎儿染色体异常73例(12.99%),包括21例(3.73%)染色体非整倍体和...     

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.     

Prenatal diagnosis of sickle-cell anemia in the first trimester of pregnancy

To investigate the usefulness of chorionic biopsy for prenatal diagnosis of sickle-cell anemia by restriction-endonuclease analysis of fetal DNA, we studied 30 pregnancies before elective abortion. When the reproducibility of the technique for obtaining adequate DNA samples was established, we successfully applied the test to five pregnancies at risk for sickle-cell anemia. In two cases, sickle-cell disease of the fetus led to a decision to terminate the pregnancy. In three other cases, a normal or AS genotype was demonstrated. One normal infant has been born, and one other pregnancy is continuing normally. In one case in which fetal death was observed three weeks after sampling, placental abnormalities found on histologic examination were compatible with a chromosomal aberration. Our study shows that chorionic biopsy is feasible for the prenatal diagnosis of sickle-cell disease before the 10th gestational week. If subsequent experience demonstrates this technique to be safe enough for mother and fetus, the ability to test in early pregnancy may make prenatal diagnosis acceptable to more couples at risk for serious genetic disorders.     

黏多糖病Ⅱ型的产前诊断

目的 应用胎儿羊水细胞艾杜糖-2-硫酸酯酶(iduronate-2-sulfatase,IDS)活性测定和基因突变检测的方法,对2例黏多糖病Ⅱ型(mucopolysaccharidosis typeⅡ,MPSⅡ)高危妊娠孕妇进行产前诊断.方法 胎儿羊水细胞培养,测定其IDS活性,并抽取羊水细胞基因组DNA,做胎儿性别鉴定和IDS基因突变检测.结果 2例胎儿羊水细胞IDS活性均明显下降,基因测序发现1例男性胎儿为IDS突变半合子,另1例女性胎儿为IDS基因突变携带者.结论 胎儿羊水细胞酶活性测定结合基因突变分析是一种准确、可靠、灵敏的MPSⅡ产前诊断方法,可对高危妊娠孕妇作出快速的产前诊断.     

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. Am. J. Med. Genet. 85:66–75, 1999. © 1999 Wiley-Liss, Inc.     

怀化地区7859例孕中期唐氏筛查和产前诊断结果分析

目的探讨孕中期唐氏筛查和产前诊断对检出胎儿染色体异常和妊娠不良结局的临床价值。方法应用时间分辨荧光免疫法对7859例孕中期(14-20周)妇女进行血清标记物三联方案(hA;FP+free-β-hCG+uE3)检测。筛查结果应用Multical软件计算21三体、18三体综合征和开放性神经管畸形的风险(rish)概率。对于高风险孕妇经遗传咨询,知情同意,自愿选择行产前诊断,于孕18-24周左右在超声引导下进行羊膜腔穿刺,抽取羊水培养进行胎儿染色体核型分析。并继续追踪胎儿和孕妇情况。结果在7859例孕妇中,筛查到高风险732例,唐氏筛查阳性率为7.65%(601/7859)。其中367例接受羊水或脐血穿刺产前诊断,占筛查高风险孕妇的50.13%(367/732);发现胎儿染色体异常16例,异常检出率4.36(16/367),其中6例唐氏综合征、5例18-三体综合征、4例Turner’s综合征、1例9号染色体臂间倒位。唐氏筛查高风险和低风险组不良妊娠结局分别为6.15%和1.46%,呈显著性差异(<0.05)。结论孕中期产前筛查是预测异常胎儿和不良妊娠结局的有效指标。结合羊水培养或脐血培养等产前诊断技术和方法,对预防先天缺陷儿出生、提高人口素质有重要临床应用价值。     

产前系统超声检查与三维/四维在胎儿畸形诊断中的意义

目的探讨二维产前系统筛查联合四维超声对产前诊断胎儿畸形的临床价值。方法我院2010年1月～2011年2月采用二维超声对11 230例孕妇,在孕22-26周进行产前系统筛查,其中汉族6170人,维吾尔族5060人,对疑似有胎儿畸形的孕妇联合应用四维超声进行诊断,并根据引产或胎儿出生后的随访结果评价其诊断率。结果 11 230例孕妇共娩出11 280(其中双胎50例)胎儿,经单纯二维超声发现畸形365例,二维与四维联合诊断的畸形391例,该组经临床证实共有的畸形407例,联合诊断的符合率为96.1%,显著高于单纯二维89.6%,P<0.05。结论二维超声是诊断胎儿畸形的首选检查方法,四维超声可动态观察胎儿体表畸形的部位,两者联合应用可以大大提高产前胎儿畸形的诊断率,有效降低出生缺陷,值得临床推广。