Karyotyping In Prenatal Diagnosis Research Articles

Additional diagnostic value of CNV-seq over conventional karyotyping in prenatal diagnosis: A systematic review and meta-analysis.

To identify the additional diagnostic value of CNV-seq over conventional karyotyping on the part of chromosomal abnormalities in prenatal diagnosis. This was a systematic review conducted in accordance with PRISMA criteria. In order to clarify related research, PubMed, Web of Science databases (including Core Collection, BIOSIS Previews, MEDLINE, and so on), The Cochrane Library and Wiley Online Library were searched with the terms: "prenatal diagnosis," "CNV-seq," "karyotyping," published from January 2010 to May 2022. No language restrictions. RenMan 5.4 was used for the meta-analysis. Eight studies were included in this systemic review and meta-analysis, including 11 091 pregnant women with high-risk pregnancy factors or with structurally abnormal fetus under ultrasound. CNV-seq detected a 2% (95% CI, -0% to 4%) additional chromosomal anomalies over conventional karyotyping in the six series. A 4% (95% CI, 3%-6%) pooled mean incremental yield of pathogenic CNVs by CNV-seq over karyotyping was observed, with a 1%-16% range. CNV-seq, applied in prenatal diagnosis, may detect more chromosomal abnormalities when compared with karyotyping. With the advantages of wide coverage, high throughput, high resolution, no culture, good compatibility, and adjustable sequencing depth, CNV-seq has high application value in prenatal diagnosis.

Prenatal diagnosis of fetuses conceived by assisted reproductive technology by karyotyping and chromosomal microarray analysis.

Invasive prenatal evaluation by chromosomal microarray analysis (CMA) and karyotyping might represent an important option in pregnant women, but limited reports have applied CMA and karyotyping of fetuses conceived by assisted reproductive technology (ART). This study aimed to examine the value of CMA and karyotyping in prenatal diagnosis after ART. This retrospective study included all singleton fetuses conceived by ART from January 2015 to December 2021. Anomalies prenatally diagnosed based on karyotyping and CMA were analyzed. Prevalence rates for various CMA and karyotyping results were stratified based on specific testing indications including isolated-and non-isolated ART groups. The rates of CMA findings with clinical significance (pathogenic/likely pathogenic) and karyotype anomalies were assessed and compared to those of local control individuals with naturally conceived pregnancies and without medical indications. In total, 224 subjects were assessed by karyotyping and CMA. In the examined patients, chromosomal and karyotype abnormality rates were 3.57% (8/224) and 8.93% (20/224), respectively. This finding indicated a 5.35% (12/224)-incremental rate of abnormal CMA was obtained over karyotype analysis (p=0.019). The risk of CMA with pathogenic findings for all pregnancies conceived by ART (5.80%, 13/224) was markedly elevated in comparison with the background value obtained in control individuals (1.47%, 9/612; p=0.001). In addition, risk of CMA with clinically pathogenic results in isolated ART groups was significant higher compared to the background risk reported in the control cohort (p=0.037). Prenatal diagnosis including karyotyping and CMA is recommended for fetuses conceived by ART, with or without ultrasound findings.

Application of chromosome microarray analysis and karyotyping in diagnostic assessment of abnormal Down syndrome screening results

BackgroundDown syndrome (DS) is the most common congenital cause of intellectual disability and also leads to numerous metabolic and structural problems. This study aims to explore the application value of chromosomal microarray analysis (CMA) and karyotyping in prenatal diagnosis for pregnant women with abnormal DS screening results.MethodsThe study recruited 1452 pregnant women with abnormal DS screening results including 493 with an enlarged nuchal translucency thickness (NT ≥ 2.5 mm) and 959 with an abnormal second-trimester maternal serum biomarker screening results. They underwent amniocentesis to obtain amniotic fluid for CMA and karyotyping.ResultsCMA identified 74/1452 abnormal results, which was more efficient than karyotyping (51/1452, P < 0.05.) CMA is equivalent to traditional karyotyping for identifying aneuploidies. Compared to karyotyping CMA identified 1.90% more copy number variants (CNVs) ranging from 159Kb to 6496Kb. However, 34.4% of them were recurrent pathogenic CNVs associated with risk of neurodevelopmental disorders. CMA identified 13 variants of uncertain significance (VUS) results and 1 maternal uniparental disomy (UPD) of chromosome 7. Karyotyping identified 3 mosaic sex chromosome aneuploidy and 4 balanced translocation which could not be identified by CMA. In enlarged NT group, karyotyping identified 80.9% abnormal results while in serum screening group karyotyping identified 35.7%. However, the incidence of pathogenic/likely pathogenic (P/LP) CNVs was nearly the same in both groups. That was because aneuploidies and gross duplication/deletion were previously screened out by NT scan.ConclusionsCMA and karyotyping have both advantages and disadvantages in prenatal diagnosis of pregnant women with abnormal DS screening results. However, there was not enough evidence to support routine CMA in pregnant women with abnormal DS screening results.

Application of the BACs-on-Beads assay for the prenatal diagnosis of chromosomal abnormalities in Quanzhou, China

BackgroundAn increasing number of techniques have been used for prenatal diagnosis of genetic abnormalities. Our initial objective was to explore the value of the BACs-on-Beads (BoBs) assay for the prenatal diagnosis of aneuploidies and microdeletion/microduplication syndromes in Quanzhou, Southeast China.MethodsA total of 1409 pregnant women with high-risk factors for chromosomal abnormalities admitted to Quanzhou Women’s and Children’s Hospital were enrolled in this study. BoBs assays and karyotype analyses were conducted for all subjects. Subsequently, chromosome microarray analysis (CMA) or fluorescence in situ hybridization (FISH) was performed to validate the findings.ResultsIn this study, karyotype analysis and BoBs assay failed in 4 cases, and 2 cases, respectively. A total of 1403 cases were successfully analyzed, with success rates of 99.72% (1405/1409) and 99.85% (1407/1409) for karyotype analysis and Bobs assay, respectively. BoBs assay rapidly detected chromosomal aneuploidies in line with the karyotyping data. Additionally, 23 cases of microdeletions/microduplications were detected by BoBs assay but missed by karyotyping, including 22q11.2 microdeletions/microduplications, 5p15.32p15.33 microdeletion, Xp22.31 microdeletions/microduplications, Xq27.3 microdeletion, and Yp11.2 and Yq11.22q11.222 microduplication. In comparison with karyotyping, fewer mosaicisms were identified by BoBs assay. A high detection rate of chromosomal abnormalities was observed in the high-risk group during noninvasive prenatal testing (NIPT) (41.72%) and the abnormal ultrasound group (13.43%).ConclusionsBoBs assay can be used for the rapid and efficient prenatal diagnosis of common aneuploidies and microdeletion/microduplication syndromes. Moreover, the combined use of BoBs assay and karyotyping in prenatal diagnosis may allow for a more effective detection of chromosomal abnormalities.

Clinical Utility of SNP Array Analysis in Prenatal Diagnosis: A Cohort Study of 5000 Pregnancies.

BackgroundSingle nucleotide polymorphism array (SNP-array) has been introduced for prenatal diagnosis. We aimed to evaluate the clinical value of SNP-array in the diagnosis of fetal chromosomal anomalies.MethodsA retrospective study was conducted on 5000 cases tested by SNP-array, and the results of 4022 cases analyzed by both karyotyping and SNP-array were compared.ResultsSNP-array analysis of 5000 samples revealed that the overall abnormality detection rate by SNP-array was 12.3%, and the overall detection rate of clinically significant copy number variations (CNVs) by SNP-array was 2.6%. SNP-array identified clinically significant submicroscopic CNVs in 4.5% fetuses with anomaly on ultrasonography, in 1.6% of fetuses with advanced maternal age (AMA), in 2.5% of fetuses with abnormal result on maternal serum screening, in 2.9% of fetuses with abnormal non-invasive prenatal testing (NIPT) results and in 3.0% of fetuses with other indications. Of the 4022 samples analyzed by both karyotyping and SNP-array, SNP-array could identify all the aneuploidy and triploidy detected by karyotyping but did not identify balanced structural chromosomal abnormalities and low-level mosaicism detected by karyotyping.ConclusionSNP-array could additionally identify clinically significant submicroscopic CNVs, and we recommend the combination of SNP-array analysis and karyotyping in prenatal diagnosis.

CGH Array and Karyotype as Complementary Tools in Prenatal Diagnosis: Prenatal Diagnosis of a 4q Derivative Chromosome from Maternal 4q;11q Translocation

ABSTRACTBackground: There is controversy whether chromosomal microarray (CMA) can replace karyotyping in prenatal diagnosis. Chromosomal microarray may detect more clinically significant chromosomal imbalances than karyotyping in a shorter time but does not detect inversions, triploidies or low mosaicisms. Case report: Amniocentesis was performed in the late second trimester based on ultrasound abnormalities. A CMA, obtained at 10 days, demonstrated a terminal deletion in 4q34.3-q35.2 and a duplication in 11q21-q25. The karyotype results, obtained 1 week later, showed a derivative chromosome 4 inherited from a maternal balanced 4;11 translocation. Conclusion: CMA and karyotype were complementary in this case, together permitting a more accurate diagnosis and genetic counseling than if only one method was used.

Rapid Prenatal Diagnosis of Common Numerical Chromosomal Abnormalities by High-Resolution Melting Analysis of Segmental Duplications

Rapid aneuploidy detection (RAD) methods constitute important complements to karyotyping in prenatal diagnosis. We evaluated the effectiveness of a method called high-resolution melting analysis of segmental duplications (SD-HRM) to serve as an alternative RAD method in prenatal diagnosis of common numerical chromosomal abnormalities (NCAs). We designed eight primary SD-HRM assays for the detection of chromosomes 13, 18, 21, X, and Y; 50 chorionic villus, 1105 amniotic fluid, and 395 cord blood samples were examined using these eight assays. For diagnosing samples that could not be diagnosed using primary assays, additional assays were designed for each target chromosome. The success rate of eight primary SD-HRM assays ranged from 99.7% to 100%. For the distinguishable analyses, these eight assays attained high diagnostic sensitivities (100%) and specificities (99.9-100%). We differentiated 53 cases of NCAs from 1550 clinical samples; subsequent reference tests revealed that these assays attained 100% clinical sensitivity and specificity. The mosaic ratio of a 45,X/46,XX sample was also precisely calculated. The SD-HRM method was able to effectively detect common NCAs in 1550 prenatal samples. We propose that SD-HRM could serve as an effective alternative option to the currently used prenatal RAD methods.

De la observación microscópica de los cromosomas en el cariotipo a los array-CGH en el diagnóstico prenatal

Introducción: el cariotipo ha sido la prueba de oro para el análisis cromosómico en el diagnóstico prenatal en los últimos cuarenta años; sin embargo, a partir del 2011 se publican múltiples artículos y los primeros meta-análisis que muestran posibles ventajas de los array-CGH (del inglés array-comparative genomic hibridization) sobre el cariotipo en el diagnóstico prenatal.Objetivo: hacer una reflexión acerca del uso de array-CGH en el diagnóstico prenatal y mostrar algunas de las potenciales ventajas y desventajas de esta prueba molecular con relación al cariotipo, así como su aplicación por obstetras, perinatólogos y especialistas en medicina materno-fetal.Conclusión: los a-CGH son una nueva alternativa en el análisis cromosómico en el diagnóstico prenatal en fetos con anomalías anatómicas; pueden usarse en todos los casos en que se justifique una intervención invasiva en el diagnóstico prenatal de alteraciones cromosómicas, y es probable que los array-CGH reemplacen al cariotipo en el diagnóstico prenatal en esta década.

0.5 Mb Array as a First-Line Prenatal Cytogenetic Test in Cases without Ultrasound Abnormalities and Its Implementation in Clinical Practice

Using whole-genome array testing instead of karyotyping in prenatal diagnosis for all indications may be desirable because of the higher diagnostic yield and shorter reporting time. The goal of this research was finding the optimal array resolution that could replace routine prenatal karyotyping in cases without ultrasound abnormalities, for example, referred for advanced maternal age or abnormal first trimester screening. As variants of unknown clinical significance (VOUS), if reported, might complicate decision-making about continuation of pregnancy, such an optimal array resolution should have a high abnormality detection rate and reveal a minimal amount of VOUS. The array data of 465 fetuses were retrospectively evaluated with several resolution levels, and the Decipher microdeletion/microduplication syndrome list was reviewed to assess what could be theoretically missed with a lower resolution. A 0.5-Mb resolution showed a high diagnostic yield potential and significantly minimized the number of VOUS. Based on our experience, we recommend genomic SNP array as a first-tier test in prenatal diagnosis. The resolution should be chosen based on the indication. In cases of fetal ultrasound abnormalities or intrauterine fetal death (IUFD), high-resolution analysis should be done. In other cases, we advise replacing karyotyping by SNP array analysis with 0.5 Mb resolution.

The future of prenatal diagnosis: karyotype, microarray or both? Technical and ethical considerations

Evaluation of: Wapner RJ, Martin CL, Levy B et al. Chromosomal microarray versus karyotyping for prenatal diagnosis. N. Engl. J. Med. 367(23), 2175–2184 (2012).Prenatal diagnosis is now offered to high-risk pregnancies, including advanced maternal age, ultrasound anomalies and positive Down’s syndrome screening, and karyotype on cultured fetal material is the test of choice to screen these pregnancies. However, microscope analysis can only detect gross chromosome abnormalities, highlighting the need for more sensitive techniques. It has recently been established that the higher resolution of microarray-based platforms can increase the diagnostic yield, offering more information to couples, and it is being discussed as a replacement to the standard karyotype. Conversely, the very high sensitivity of microarray-based analysis allows us to detect small microdeletions/microduplications (copy number variations) with unknown functional role and difficult genotype/phenotype correlation. In addition, the new copy number variation syndromes are often associated with variable outcomes, ranging from normal to severely affected individuals. This means that the microarray-based analysis introduced routinely in prenatal diagnosis needs to answer the question: are laboratory staff, clinical geneticists and counselors really experienced enough to manage these new scenarios?

725: A retrospective study of BACs-on-Beads (BoBs) technology for identification of chromosome abnormalities compared with QF-PCR and karyotyping in prenatal diagnosis

sion was performed to control for confounding variables. RESULTS: 309 women had CVS performed and also had pregnancy outcomes available in our database. Absence of villi buds was associated with preterm birth (p .001) and GDM (p .005). 92.6% of samples had composite scores of 2-6. High composite score (7-9) was associated with gestational hypertension (p 0.038) and 5 minute Apgar less than 7 (p 0.032). Both high (7-9) and low (0-1) composite scores were associated with preterm delivery (p 0.002). Low composite score was associated with GDM (p 0.003). Gestational age at procedure was associated with morphology (p 0.00). The association of high or low composite morphology score with these outcomes remained significant in the logistic regression analysis. CONCLUSION: Morphologic characteristics of chorionic villi already demonstrate abnormal features in the late first trimester in some pregnancies destined for poorer obstetric outcomes. Identifying the underlying molecular etiology responsible for underor overdeveloped chorionic villi may aid in a greater understanding of the molecular mechanisms leading to these adverse pregnancy outcomes.

Economic evaluation of multiplex ligation-dependent probe amplification and karyotyping in prenatal diagnosis: a cost-minimization analysis

PurposeTo assess the cost-effectiveness of Multiplex Ligation-dependent Probe Amplification (MLPA, P095 kit) compared to karyotyping.MethodsA cost-minimization analysis alongside a nationwide prospective clinical study of 4,585 women undergoing amniocentesis on behalf of their age (≥36 years), an increased risk following first trimester prenatal screening or parental anxiety.ResultsDiagnostic accuracy of MLPA (P095 kit) was comparable to karyotyping (1.0 95% CI 0.999–1.0). Health-related quality of life did not differ between the strategies (summary physical health: mean difference 0.31, p = 0.82; summary mental health: mean difference 1.91, p = 0.22). Short-term costs were lower for MLPA: mean difference €315.68 (bootstrap 95% CI €315.63–315.74; −44.4%). The long-term costs were slightly higher for MLPA: mean difference €76.42 (bootstrap 95% CI €71.32–81.52; +8.6%). Total costs were on average €240.13 (bootstrap 95% CI €235.02–245.23; −14.9%) lower in favor of MLPA. Cost differences were sensitive to proportion of terminated pregnancies, sample throughput, individual choice and performance of tests in one laboratory, but not to failure rate or the exclusion of polluted samples.ConclusionFrom an economic perspective, MLPA is the preferred prenatal diagnostic strategy in women who undergo amniocentesis on behalf of their age, following prenatal screening or parental anxiety.Electronic supplementary materialThe online version of this article (doi:10.1007/s00404-011-1921-y) contains supplementary material, which is available to authorized users.

Array technology in prenatal diagnosis

Array technology, here termed molecular karyotyping, is an attractive alternative to conventional karyotyping for prenatal diagnosis given the increase in resolution as well as faster report times. We review the benefits and limitations of this technique for the detection of pathogenic genomic imbalances, address the challenges raised in the interpretation of copy number variations, discuss practical considerations for the routine implementation of molecular karyotyping in prenatal diagnosis, and identify areas where more research is desired to enable large scale introduction of the technique(s).

Additional information from array comparative genomic hybridization technology over conventional karyotyping in prenatal diagnosis: a systematic review and meta-analysis

Additional information from array comparative genomic hybridization technology over conventional karyotyping in prenatal diagnosis: a systematic review and meta-analysis

Additional information from array comparative genomic hybridization technology over conventional karyotyping in prenatal diagnosis: a systematic review and meta‐analysis

Array comparative genomic hybridization (CGH) is transforming clinical cytogenetics with its ability to interrogate the human genome at increasingly high resolution. The aim of this study was to determine whether array CGH testing in the prenatal population provides diagnostic information over conventional karyotyping. MEDLINE (1970 to December 2009), EMBASE (1980 to December 2009) and CINAHL (1982 to December 2009) databases were searched electronically. Studies were selected if array CGH was used on prenatal samples or if array CGH was used on postnatal samples following termination of pregnancy for structural abnormalities that were detected on an ultrasound scan. Of the 135 potential articles, 10 were included in this systematic review and eight were included in the meta-analysis. The pooled rate of extra information detected by array CGH when the prenatal karyotype was normal was meta-analyzed using a random-effects model. The pooled rate of receiving an array CGH result of unknown significance was also meta-analyzed. Array CGH detected 3.6% (95% CI, 1.5-8.5) additional genomic imbalances when conventional karyo-typing was 'normal', regardless of referral indication. This increased to 5.2% (95% CI, 1.9-13.9) more than karyotyping when the referral indication was a structural malformation on ultrasound. There appears to be an increased detection rate of chromosomal imbalances, compared with conventional karyotyping, when array CGH techniques are employed in the prenatal population. However, some are copy number imbalances that are not clinically significant. This carries implications for prenatal counseling and maternal anxiety.

Additional information from array comparative genomic hybridisation technology over conventional karyotyping in prenatal diagnosis–a systematic review and meta-analysis

BackgroundArray comparative genomic hybridisation (array CGH) is transforming clinical cytogenetics with its ability to interrogate the human genome at increasingly high resolution.ObjectiveTo determine whether array CGH testing in the prenatal...

Comparison of Multiplex Ligation-Dependent Probe Amplification and Karyotyping in Prenatal Diagnosis

To estimate whether multiplex ligation-dependent probe amplification (MLPA), a molecular technique used for detecting the most common chromosomal aneuploidies, is comparable with karyotyping for the detection of aneuploidies of chromosomes X, Y, 13, 18, and 21 in routine clinical practice and to estimate the costs differences of both techniques. In this prospective, nationwide cohort study, we consecutively included 4,585 women who had an amniocentesis because of their age (36 years or older), increased risk after prenatal screening, or maternal anxiety. Amniotic fluid samples were tested independently with both MLPA and karyotyping. The primary outcome was diagnostic accuracy of MLPA to detect aneuploidies of chromosomes X, Y, 13, 18, and 21. Secondary outcome measures were turnaround time for test results and costs. A sample size was calculated using a critical noninferiority margin of 0.002; therefore, at least 4,497 paired test results were needed (one-sided alpha 0.05, power 0.90). Diagnostic accuracy of MLPA was 1.0 (95% confidence interval [CI] 0.99-1.0), sensitivity was 100% (95% CI 0.96-1.0) and specificity was 100% (95% CI 0.999-1.0). Diagnostic accuracy of MLPA was statistically similar (noninferior) to that of karyotyping (P<.001). In 75 cases, MLPA failed (1.6%); karyotyping failed once (0.02%). Compared with karyotyping, MLPA shortened the waiting time by 14.5 days (P<.001, 95% CI 14.3-14.6) and cost less (-47, P<.001). In routine clinical practice, diagnostic accuracy of MLPA for detection of trisomies X, Y, 13, 18, and 21 is comparable with that of karyotyping, and it reduces waiting time at lower costs. II.

P247: Rapid karyotyping or full karyotyping for prenatal diagnosis: results of a prospective study in a London teaching hospital

P247: Rapid karyotyping or full karyotyping for prenatal diagnosis: results of a prospective study in a London teaching hospital

Rapid karyotyping in prenatal diagnosis: A comparative study of the ‘pipette method’ and the ‘in situ’ technique for chromosome harvesting

Rapid karyotyping in the second and third trimesters has important implications for the management of pregnancies at risk. From September 1985 to March 1992, 735 amniotic fluid samples sent to our laboratory for rapid karyotyping from 64 different diagnostic centres of the Federal Republic of Germany were included in a comparative study on harvesting for chromosome analysis using the 'pipette method' or the 'in situ' technique. The average time between preparation of the amniotic fluid and verbal notification of the analysed karyotype was 5.41 days. The 'pipette method' needed on average 4.65 days, and the 'in situ' technique 5.97 days. In comparison with other more invasive techniques available for rapid karyotyping such as cordocentesis and placental biopsy, amniocentesis and subsequent chromosome harvesting using the 'pipette method' and/or the 'in situ' technique proved very useful and efficient. The overall incidence of chromosome aberrations was 15.3 per cent. The high rate of structural chromosome aberrations and uncommon aneuploidies found in our investigation (12 per cent) indicates that for rapid karyotyping in the second and third trimesters, conventional cytogenetic techniques cannot be replaced by faster techniques based on fluorescent in situ hybridization on interphase cells in the near future.

A pipette method for rapid karyotyping in prenatal diagnosis.

The "pipette method' is introduced as a method of prenatal diagnosis which is in competition with the "in situ' and the "trypsinization' technique. It is sufficiently standardized for routine diagnosis and the banding techniques currently used in prenatal diagnosis (G, Q, C-banding and NOR) have been adapted for it. In 180 cases from 27 different centres, the "pipette method' was employed for chromosomal harvesting in order to save time. An average of 6 X 6 days was taken to achieve a result. There was a pathological karyotype in 28 cases (16.1 per cent) and this high proportion can be related to cases where ultrasound scan has led to a diagnosis of "suspected chromosomal abnormality.' This technique is also of use in advanced stages of pregnancy. The early recognition of the fetal karyotype can contribute to the future management of the pregnancy. The "pipette method' can also be used in chromosomal harvesting of tumour cells and fibroblast cultures.