Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Noninvasive prenatal testing”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

Identification of rare maternal copy number variants by genome-wide analysis of noninvasive prenatal screening data in 113,017 pregnant women.

OBJECTIVES: Knowledge of copy number variants (CNVs) is relevant to maternal and fetal health and can be obtained from noninvasive prenatal screening (NIPS) of pregnancy. However, genome-wide analysis of maternal CNVs using NIPS data has not been conducted in large populations. METHODS: For CNV analysis, the human genome was segmented into 10 kilobase pairs (Kb) bins, and the relative sequencing depth of each bin was calculated. The circular binary segmentation algorithm was used to estimate CNVs. Detected CNVs from two pregnancies of the same participant were compared to validate the reproducibility. All CNVs were merged into CNV regions (CNVRs) to evaluate their frequency, distributions, and relationship with disease-related genes and regions. RESULTS: In this study, 113,017 pregnant women were recruited. A total of 363,886 CNVs larger than 50 Kb were detected in 101,779 individuals and merged into 43,005 CNVRs. For evaluating the reproducibility of CNVs, 90.18% of deletions and 88.07% of duplications were consistent. In general, 78.13% of individuals carried CNVRs that overlapped protein-coding genes, while 14.76% overlapped OMIM genes. We detected 246 novel CNVRs, 134 (54.47%) involving protein-coding genes. For the perspective of maternal-fetal health, we identified 4,984 (4.41%) individuals as carriers of 5,243 CNVs containing known pathogenic or likely pathogenic regions, including 22q11.2 region and DMD gene.. CONCLUSIONS: NIPS sequencing data is a reliable source for maternal CNV detection. These CNVs constitute an integrate component in maternal-fetal health management.

Humans↗

Trophoblast Enrichment by Maternal Immune-Cell Depletion Using CD45 and CD56 Surface Markers in Trophoblast Retrieval and Isolation from the Cervix (TRIC).

Background: Trophoblast retrieval and isolation from the cervix (TRIC) has emerged as a promising alternative to invasive prenatal diagnostic procedures. However, contamination by maternal immune cells remains a major challenge that may compromise trophoblast purity and the reliability of downstream fetal genetic analyses. Methods: Maternal immune cells were selectively depleted by immunomagnetic sorting using antibodies targeting CD45 or CD56. The remaining cells were subsequently enriched for HLA-G-positive trophoblasts and characterized by immunofluorescence and gene-expression analyses using CD45, CD56, HLA-G, cytokeratin 7 (CK7), and β-human chorionic gonadotropin (β-hCG). Results: Compared with CD45-mediated depletion, CD56-mediated depletion demonstrated more efficient removal of maternal immune cells, as indicated by significantly reduced CD56 expression. CK7 expression showed an increasing trend following CD56 depletion, whereas β-hCG expression remained largely unchanged. Immunofluorescence analysis further demonstrated a significant increase in the proportion of CK7+/β-hCG+ trophoblast cells after CD56 depletion. Conclusions: Among the evaluated depletion strategies, CD56-mediated depletion demonstrated a more favorable profile for trophoblast-associated characteristics than CD45-mediated depletion, suggesting its potential contribution to further methodological optimization of trophoblast isolation in TRIC-based noninvasive prenatal genetic testing.

maternal immune cell↗

Detection of interleukin-6 in vaginal secretions of women with preterm premature rupture of membranes and its association with neonatal infection: a rapid immunochromatographic test.

OBJECTIVE: The purpose of this study was to evaluate the diagnostic value of an interleukin-6 (IL-6) bedside test of vaginal secretions for neonatal infection in cases of preterm premature rupture of membranes. STUDY DESIGN: This prospective clinical study included 73 patients. Interleukin-6 protein in vaginal secretions was determined with an immunochromatographic bedside test in <20 minutes. RESULTS: Elevated C-reactive protein level (>20 mg/dL; odds ratio, 5.1; 95% CI, 0.9-28.6) and positive interleukin-6 level (odds ratio, 4.6; 95% CI, 1.2-18.4) were both associated with neonatal infection. After adjustment, only interleukin-6 remained associated with neonatal infection (odds ratio, 4.5; 95% CI, 1.1-18.5). The sensitivity of interleukin-6 for the prediction of neonatal infection was 79% (95% CI, 65-92); its specificity was 56% (95% CI, 42-70); its positive predictive value was 30% (95% CI, 12-47), and its negative predictive value was 92% (95% CI, 84-99). CONCLUSION: Interleukin-6 protein determination by this new immunochromatographic test is a noninvasive prenatal vaginal marker of neonatal infection.

Adult↗

Recent advances in prenatal screening and diagnosis of genetic disorders.

In any pregnancy, there is an approximate 3% to 5% chance that a fetal complication will occur. The most familiar prenatal diagnostics cannot be performed until the fetus is well into gestation, and most involve invasive procedures along with their inherent risks. In light of these facts, many noninvasive prenatal screening and diagnostic tests have been developed, the newest using recombinant deoxyribonucleic acid (DNA) technology in the examination of fetal cells. Through these procedures, genetic coding errors and chromosomal disruptions may be detected. This article discusses the currently available prenatal and screening diagnostic tests for genetic disorders with a focus on the latest technology.

Female↗

Detection of fetal messenger ribonucleic acid in maternal blood to determine fetal RhD status as a strategy for noninvasive prenatal diagnosis.

OBJECTIVES: Our purpose was to test the hypothesis that reverse transcriptase-polymerase chain reaction for fetal messenger ribonucleic acid in maternal blood is more sensitive than polymerase chain reaction from genomic deoxyribonucleic acid in prenatal determination of fetal RhD blood type. STUDY DESIGN: Fetal nucleated erythrocytes in peripheral blood from 35 RhD-negative women were enriched by triple-density gradient centrifugation, anti-CD71 magnetic sorted, and deoxyribonucleic acid and ribonucleic acid extracted. Sensitivities of reverse transcriptase-polymerase chain reaction and polymerase chain reaction were compared to predict definitive fetal RhD blood type determined in fetal tissues. RESULTS: Reverse transcriptase-polymerase chain reaction was significantly more accurate (P = .03) than genomic-polymerase chain reaction in predicting fetal RhD blood type, both overall (28 of 35 vs 22 of 35) and when the fetus was RhD-positive (12 of 19 vs 6 of 19). CONCLUSIONS: Reverse transcriptase-polymerase chain reaction is more sensitive than genomic-polymerase chain reaction in detection of fetal RhD sequences in maternal blood.

Female↗

Circulating placental RNA in maternal plasma is associated with a preponderance of 5' mRNA fragments: implications for noninvasive prenatal diagnosis and monitoring.

BACKGROUND: The molecular characteristics of placental RNA circulating in maternal plasma are unknown. We investigated the integrity of circulating placental RNA in maternal plasma and tested the relevance of plasma RNA integrity for noninvasive prenatal diagnosis. METHODS: Six different placental transcripts and mRNA of the housekeeping gene glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were quantified for the 5' and 3' regions in maternal plasma by 1-step real-time reverse transcription-PCR (RT-PCR) assays. This quantitative strategy was validated by 2-step RT-PCR and serial dilution experiments. The rates of detection by the 5' and 3' assays for the beta-subunit of human chorionic gonadotropin (beta hCG) were assessed in maternal plasma samples collected from different gestational periods. RESULTS: For 5 of the 7 genes, the plasma mRNA concentrations measured by the 5' amplicons were significantly higher than those measured by the corresponding 3' amplicons. Every transcript under study demonstrated a higher rate of detection in the 5' assay than in the 3' assay in maternal plasma. In particular, the detection rate of beta hCG mRNA in maternal plasma was increased throughout gestation when the 5' assay was used. CONCLUSIONS: Circulating placental RNA is associated with a preponderance of 5' mRNA fragments in maternal plasma. Apart from its intrinsic biological interest, this information could have important implications for the development of new assays targeting fetal RNA markers for noninvasive prenatal diagnosis and monitoring.

Chorionic Gonadotropin↗

Prenatal diagnosis using fetal cells from the maternal circulation.

All current methods of fetal karyotyping are invasive and carry a definite, albeit small, procedure-related risk. Because of this and testing costs, only women older than 35 years who have a greater risk for fetal aneuploidy are currently offered prenatal testing. But this detects only 20% to 25% of fetuses with Down syndrome. It would be a tremendous advance to find a noninvasive technique for prenatal diagnosis that carries no procedure-related risk and could be offered to all pregnant women. We describe a possible technique for noninvasive prenatal diagnosis that aims to identify fetal cells in the peripheral maternal circulation and successfully garner them for prenatal testing. Early attempts at fetal karyotyping were hampered by inaccurate diagnostic methods and cumbersome cell-counting techniques. Today, improved capabilities of identifying and enriching for fetal cells, coupled with sensitive methods of analysis such as the polymerase chain reaction, bring renewed enthusiasm to this task. Many technical issues, as well as serious questions regarding the test's utility, still exist, however, and must be explored and answered before the capture of fetal cells in the maternal circulation translates into reality for noninvasive prenatal diagnosis.

Antibodies, Monoclonal↗

[The triple test].

Until the late 80s advanced maternal age was the main indication for prenatal chromosomal diagnosis. The triple test has introduced a noninvasive method for all women to determine the risk of chromosomal abnormality. Not only women aged over 35 years, but also those less than 35 years of age may benefit from the triple test. An exactly performed triple test will allow a diagnosis in 70% of all cases with trisomy 21. Additionally, a positive triple test will be found in 9% of all screened women. 1-2% of the women with a positive triple test will exhibit a fetus with trisomy 21. A false-negative result will be found in 0.1%. Beside trisomy 21, the triple test allows also the diagnosis of pregnancies with a high risk of trisomy 18 and Turner syndrome. The value of the triple test is mainly determined by the quality of the laboratory and the exactness of the determination of the gestational age, which is done mainly by means of ultrasound. Ultrasound investigation also provides information about structural abnormalities. In future the triple test will increase in accuracy and it will be performed in the first trimester.

Chromosome Aberrations↗

The search for fetal cells in the maternal circulation.

Currently, all methods of prenatal diagnosis require an invasive approach. The next step in the continuing challenge to make prenatal diagnosis more accessible is the development of a noninvasive test. The presence of fetal cells in the maternal circulation has been debated for several decades, but traditional attempts to identify the rare fetal cell within the pool of maternal cells have met with partial success at best. Today, with the aid of highly sensitive and specific techniques such as fluorescent activated cell sorting, polymerase chain reaction, and in-situ hybridization, the task of finding the "on-in-a-million" fetal cell is moving from the realm of the imagination into that of reality.

Blood Cells↗

Ionizing radiation and the developing brain.

The unique susceptibility of the central nervous system to radiation exposure is attributable to its extensive period of development, the vulnerability of its neuronal cells, the migratory activity of many of its cells, its inability to replace mature neurons, and the complexity of the system itself. Radiation effects may be due to glial or neuronal cell death, interruption of migratory activity, impaired capacity to establish correct connections among cells, and/or alterations in dendritic development. These structural changes are often manifested as behavioral alterations later in life. Sensitivity to radiation (dose-response) is markedly similar among all mammalian species when developmental periods are compared. This review compares and contrasts human and animal behavioral data. Neonatal and postnatal adult behavioral tests have been shown to be sensitive, noninvasive measures of prenatal radiation exposure, although currently their predictive validity for humans is uncertain. Additional research is needed to determine the presence and significance of postnatal morphologic and functional alterations due to prenatal exposure to low levels of ionizing radiation.

Animals↗

Glycogen storage disease type 1a in Israel: biochemical, clinical, and mutational studies.

Glycogen storage disease type 1a (von Gierke disease, GSD 1a) is caused by the deficiency of microsomal glucose-6-phosphatase (G6Pase) activity which catalyzes the final common step of glycogenolysis and gluconeogenesis. The recent cloning of the G6Pase cDNA and characterization of the human G6Pase gene enabled the characterization of the mutations causing GSD 1a. This, in turn, allows the introduction of a noninvasive DNA-based diagnosis that provides reliable carrier testing and prenatal diagnosis. In this study, we report the biochemical and clinical characteristics as well as mutational analyses of 12 Israeli GSD 1a patients of different families, who represent most GSD 1a patients in Israel. The mutations, G6Pase activity, and glycogen content of 7 of these patients were reported previously. The biochemical data and clinical findings of all patients were similar and compatible with those described in other reports. All 9 Jewish patients, as well as one Muslim Arab patient, presented the R83C mutation. Two Muslim Arab patients had the V166G mutation which was not found in other patients' populations. The V166G mutation, which was introduced into the G6Pase cDNA by site-directed mutagenesis following transient expression in COS-1 cells, was shown to cause complete inactivation of the G6Pase. The characterization of all GSD 1a mutations in the Israeli population lends itself to carrier testing in these families as well as to prenatal diagnosis, which was carried out in 2 families. Since all Ashkenzai Jewish patients harbor the same mutation, our study suggests that DNA-based diagnosis may be used as an initial diagnostic step in Ashkenazi Jews suspected of having GSD 1a, thereby avoiding liver biopsy.

Arabs↗

Peroxisomal disorders.

Disorders of peroxisome function result in severe and progressive neurologic deficits. Knowledge of these disorders and their role in neurodegenerative disorders has been growing rapidly over the last 40 years. Noninvasive diagnostic tests can identify all of the peroxisomal disorders, many of them prenatally. The genetic basis of some of these peroxisomal disorders is being established, which will advance understanding of their pathobiology and provide clues for therapeutic interventions.

Adolescent↗

Noninvasive determination of fetal RhD status using fetal DNA in maternal serum and PCR.

OBJECTIVE: Because prenatal testing of fetal RhD status by amniocentesis carries small yet finite risks to the fetus and mother, this study sought to determine whether fetal DNA in maternal serum could be used to detect fetal RhD status by polymerase chain reaction (PCR). METHODS: A retrospective analysis was made of frozen serum specimens from 20 sensitized RhD-negative pregnant women (ranging from 15.0 to 36.0 weeks' gestation) who were confirmed by serology at birth to have been carrying RhD-positive fetuses. Eleven serum specimens from RhD-negative individuals served as controls. DNA was isolated from serum and used in two PCR-based methods to detect a 99 base pair (bp) DNA fragment specific for the RhD gene and a 113 bp fragment specific for the RhCE gene as control. RESULTS: Overall, in 14 (70%) of 20 RhD-positive fetuses the 99 base pair RhD-specific PCR product was detected. There was no false positive detection among the 11 control serum specimens. CONCLUSION: The results illustrate the ability to detect fetal RhD sequences in maternal serum of sensitized women. Moreover, the findings demonstrate that fetal single-gene disorders can be detected prenatally by using DNA isolated only from maternal serum.

Blood Grouping and Crossmatching↗

Prenatal diagnosis and fetal therapy.

The protective effect of folic acid supplementation has been demonstrated in patients at risk of neural tube defects by a large, randomized double-blind study. The feasibility of second-trimester screening for Down syndrome, based on the combination of maternal and biochemical markers on maternal blood, has also been verified in two large series from both the United Kingdom and the United States. These results represent major advances in the field of prenatal diagnosis, which, in the future, is likely to rely more and more on better selection by noninvasive testing of high-risk patients. The emphasis has moved away from very early invasive testing due to concerns related to the safety of both early chorionic villus sampling and amniocentesis. Evaluation of renal damage in fetuses with obstructive uropathy by analysis of urinary biochemistry may constitute the basis for more efficient selection of cases amenable to antenatal treatment. Twin-to-twin transfusion syndrome remains a challenge for the future.

Congenital Abnormalities↗

Interleukin-8 mRNA in vaginal secretions: a prenatal marker of congenital infection in case of preterm labor with intact membranes.

OBJECTIVE: To study whether interleukin-8 (IL-8) mRNA in vaginal secretions is associated with congenital infection and preterm delivery in the case of preterm labor with intact membranes. METHODS: This prospective clinical study in a tertiary referral center included 280 patients who gave birth to 360 infants from 1997 through 1999. IL-8 mRNA in vaginal secretions was determined with reverse transcriptase polymerase chain reaction. Logistic regression was used to examine the association between vaginal IL-8 mRNA and congenital infection independently of the time of birth. Main outcome measures were congenital infection and delivery before 37 and 33 weeks' gestation. RESULTS: A total of 100 women (100/280 (35.7%)) gave birth before 37 weeks. A total of 54 children (54/360 (15%)) had congenital infection. IL-8 mRNA in vaginal secretions was associated with delivery within 14 days of the sampling (24 (15.6%) vs. 7 (5.6%) p < 0.01), but not with delivery within 48 h, 7 days (p = 0.07) or before 37 or 33 weeks. There were more congenital infections in the group with detectable IL-8 mRNA (37 (19.3%) than in the negative group (17 (10.1%); p < 0.05). IL-8 mRNA was associated with congenital infection independently of the time of birth (OR: 2.6 (1.3-5.1)). This test had a sensitivity for predicting neonatal infection of 69%. Its specificity was 49%, its positive predictive value 19%, and its negative predictive value 90%. CONCLUSION: IL-8 mRNA could be a prenatal noninvasive vaginal marker of congenital infection.

Adult↗

Molecular genetic testing for prenatal diagnosis.

In the past few decades, enormous progress has been made in the field of prenatal molecular genetic testing. Based on the inheritance patterns of the disease and type of mutation, prenatal diagnosis is possible using direct or indirect methods of detection. Although direct mutation analysis is highly accurate, accuracy of indirect mutation analysis depends on the distance of the DNA marker to the disease locus. In the past decade, the discovery of new concepts--such as atypical inheritance patterns due to UPD and imprinting and triplet repeat disorders--have helped to increase understanding of the molecular basis of these unusual genetic disorders. Prenatal diagnosis using a single cell from a blastomere is rapidly becoming routine in clinical practice. Noninvasive procedures to obtain fetal DNA for molecular testing also are progressing very rapidly. With the completion of the genome project, resources now are available for developing new technologies, such as microarrays (DNA chips), for accurate, simultaneous, mutation detection. The next few decades hold the promise of many more advances in genetic testing, drug discovery, and therapy.

Adult↗

Depressive reactions and stress related to prenatal medicine procedures.

OBJECTIVE: The experience of pregnancy is mainly influenced by the availability of prenatal screening procedures. Previous screening studies focus on somatic abnormalities. The psychological experience of the parents-to-be recedes into the background. The purpose of the present study was to analyze the emotional mood of pregnant women and their partners before and their psychological stress before and after different prenatal screening procedures (ultrasound, chorionic villus sampling or amniocentesis). METHODS: In the study, 140 pregnant women, and, in 108 cases, their partners, were asked to complete questionnaires before and immediately after the prenatal testing. Depending on the applied prenatal procedure, the subjects were assigned to: the invasive group (amniocentesis or chorionic villus sampling) and the noninvasive group (ultrasound group). We used the German version of the Centre for Epidemiological Studies-Depression Scale of Hautzinger and the short questionnaire of actual situative perceived stress of Müller. RESULTS: Before the prenatal examination, the mean level of depression of pregnant women was the highest in the noninvasive group compared to the invasive group, although the between-group difference was not significant. However, for their male partners, the mean level of depression was significantly different between the noninvasive and the invasive groups. Furthermore, women undergoing invasive diagnostic or noninvasive diagnostic procedures were significantly more depressed than their partners. The analysis of the actual stress ratings showed a significant reduction from the prescreening to the postscreening stress for pregnant women and their partners in both groups. CONCLUSIONS: This study reveals that the individual experience of prenatal diagnosis is not determined by the invasiveness of the procedure. Immediate visual presentation of the fetus and confirmation of a normal test result reduce stress that has previously been induced by the prenatal test itself. This contradiction should be discussed with the parents.

Adult↗

Noninvasive means of identifying fetuses with possible Down syndrome: a review.

Women who are 35 years or older are offered invasive prenatal testing because of the increased risk of chromosomal abnormalities, especially Down syndrome. In an attempt to increase the number of Down syndrome fetuses being detected and decrease the number of invasive procedures being performed on pregnancies not affected with a chromosome abnormality, both biochemical and ultrasound screening methods are being studied and are summarized in this article. The ultrasound markers reviewed include increased nuchal thickness, increased nuchal lucency, shortened femur, shortened humerus, pyelectasis, hypoplastic ears, echogenic intracardiac focus, hypoplasia of the fifth middle phalanx, and echogenic bowel.

Adult↗