Recent advances in prenatal genetic screening and testing

Congenital heart diseases (CHDs) and forensic investigations: Searching for the cause of death

Congenital Heart Diseases (CHDs) are a group of structural abnormalities or defects of the heart that are present at birth. CHDs could be connected to sudden death (SD), defined by the WHO (World Health Organization) as "death occurring within 24 h after the onset of the symptoms" in an apparently "healthy" subject. These conditions can range from relatively mild defects to severe, life-threatening anomalies. The prevalence of CHDs varies across populations, but they affect millions of individuals worldwide. This article aims to discuss the post-mortem investigation of death related to CHDs, exploring the forensic approach, current methodologies, challenges, and potential advancements in this challenging field. A further goal of this article is to provide a guide for understanding these complex diseases, highlighting the pivotal role of autopsy, histopathology, and genetic investigations in defining the cause of death, and providing evidence about the translational use of autopsy reports. Forensic investigations play a crucial role in understanding the complexities of CHDs and determining the cause of death accurately. Through collaboration between medical professionals and forensic experts, meticulous examinations, and analysis of evidence, valuable insights can be gained. These insights not only provide closure to the families affected but also contribute to the prevention of future tragedies.

A Case of Type 2 Diastematomyelia With Spina Bifida in a Pediatric Female Patient

This case report presents the clinical and radiological findings of a seven-year-old female with type 2 diastematomyelia and spina bifida, emphasizing the complexity of congenital spinal anomalies in pediatric patients. The patient presented with a two-month history of lower back pain, prompting diagnostic investigations. Radiographic examination revealed spina bifida at the L3-L5 levels, subsequently confirmed by magnetic resonance imaging (MRI), which disclosed bifid spinous processes, an absent posterior arch, and a split spinal cord terminating at the L3-L4 disc levels. The Vancouver classification system facilitated a standardized characterization of congenital spinal anomalies. The multidisciplinary approach involving orthopedic and neurosurgical specialists led to a conclusive diagnosis of type 2 diastematomyelia with simple spinal dysraphism. Surgical intervention, encompassing laminectomy and correction of the split spinal cord, was successfully performed, resulting in the stabilization of the patient. This case underscores the importance of early diagnosis, advanced imaging modalities, and collaborative management in addressing rare congenital spinal anomalies. The discussion delves into the clinical implications, diagnostic challenges, and the pivotal role of surgical intervention. Insights from this case contribute to the existing literature, guiding healthcare professionals in understanding and managing similar cases with potential implications for future research and treatment strategies.

Causes of death in individuals with trisomy 18 after the first year of life

Mortality in individuals with trisomy 18 has significantly decreased over the past 20 years, but there is scant literature addressing the prognosis and cause of death in individuals with trisomy 18 and survival past the first year of life (YOL). This study analyzed factors associated with mortality and cause of death in a retrospective cohort of 174 individuals with trisomy 18 and survival past the first YOL, the largest such series to date. Data were collected via retrospective survey of parents of affected individuals. Prenatal diagnosis of trisomy 18; postnatal respiratory distress; maternal age > 35 years; birthweight <2000 g; brain and spinal cord defect(s); atrial and/or ventricular septal defect(s); inability to feed orally without medical assistance; and failure to meet sitting and rolling milestones were associated with mortality in this sample. Cause of death was compared between our cohort of individuals with trisomy 18 and existing literature on those with mortality before the first YOL. Individuals with trisomy 18 with mortality after the first YOL demonstrated a predominance of infectious (n = 10/22) and postoperative (n = 6/22) contributing causes of death, in contrast to the existing literature, which shows a predominance of cardiopulmonary causes of death (e.g., cardiopulmonary arrest, pulmonary hypertension). These findings demonstrate that individuals with trisomy 18 and survival past the first YOL have unique medical needs, but further research is needed to develop clinical guidelines for this growing population.

Human Genetics of Congenital Heart Defects

Congenital heart diseases (or congenital heart defects/disorders; CHDs) are structural abnormalities of the heart and/or great vessels that are present at birth. CHDs include an extensive range of defects that may be minor and require no intervention or may be life-limiting and require complex surgery shortly after birth. This chapter reviews the current knowledge on the genetic causes of CHD.

Prenatal politics: fetal surgery, abortion and disability rights in the United States

While fetal surgery-and pregnancy termination as a possible therapeutic alternative-have been examined in a number of studies, very few have addressed the issues and tensions that arise when prenatal surgery is considered from the standpoint of Disability Studies. This article will expose these concerns by tracing the medical development of fetal surgery; the arguments for and against prenatal surgery; and the connections between fetal surgery, abortion, and disability rights. Like other dimensions of the life cycle that involve reproduction, prenatal surgery has become highly politicized in the United States which has, to a certain extent, stalled critical discussion. However, the skepticism with which many disability rights advocates and policymakers approach prenatal medical intervention in general has opened a new space for active debate concerning fetal surgery in terms of how it medicalizes pregnancy, pathologizes diversity, contributes to the valuation of life, and emphasizes 'perfect babies' at any cost.

Novel Approaches to an Integrated Route for Trisomy 21 Evaluation

Trisomy 21 (T21) is one of the most commonly occurring genetic disorders, caused by the partial or complete triplication of chromosome 21. Despite the significant progress in the diagnostic tools applied for prenatal screening, commonly used methods are still imprecise and involve invasive diagnostic procedures that are related to a maternal risk of miscarriage. In this case, novel prenatal biomarkers are still being evaluated using highly specialized techniques, which could increase the diagnostic usefulness of biochemical prenatal screening for T21. From the other hand, the T21′s pathogenesis, caused by the improper division of genetic material, disrupting many metabolic pathways, could be further evaluated with the use of omics methods, which could result in bringing relevant insights for the evaluation of potential medical targets. Accordingly, a literature search was undertaken to collect novel information about prenatal screening for Down syndrome with the use of advanced technology, with a particular emphasis on the evaluation of novel screening biomarkers and the discovery of potential medical targets. These meta-analyses are focused on novel approaches designed with the use of omics techniques, representing the most rapidly developing and promising field in research today. Considering the limitations and progress of these methods, the use of omics techniques in evaluating T21 pathogenesis could bring beneficial results in prenatal screening, simultaneously uncovering novel potential medical targets.

The Results of a Prospective Cohort Study of the Effectiveness of the Algorithm for Monitoring Pregnancies in Patients from the Group of High Perinatal Risk to Reduce Perinatal Losses and Improve Neonatal Outcome

Prenatal prognosis is an important part of obstetric care, which aims to reduce fetal and neonatal losses. A differentiated approach to the management of different risk groups allows you to optimize existing approaches. The objective: сomparison of pregnancy results in the high perinatal risk group using the proposed monitoring algorithms and the traditional method of management in a prospective cohort study. Materials and methods. The prospective cohort study was conducted from 2016 to 2018 on the basis of the medical center LLC «Uniclinica», Medical Genetics Center «Genome», Clinic of Reproductive Genetics «Victoria», Kyiv City Maternity Hospital №2. 580 women were included in the final analysis. Exclusion criteria were: low risk (0–2) according to the adapted antenatal risk scale (Alberta perinatal health program), multiple pregnancy, critical malformations and chromosomal abnormalities of the fetus, lack of complete information about the outcome of pregnancy, lack of results of all intermediate clinical and laboratory surveys. Results. The introduction of a comprehensive differentiated approach has improved the diagnosis of late forms of growth retardation (OR 4,14 [1.42–12.09]; p=0,009), reduced the frequency of urgent cesarean sections (OR 1,61 [1,03–2,49]; p=0,046) and reduced perinatal mortality [1,09–21,3]; р=0,041) due to reduction of antenatal losses (OR 2,2 [1,06–4,378]; р=0,045). There was a significant increase in the frequency of planned cesarean sections (p<0,0001, without affecting the total number of operative deliveries) and statistically insignificant, but tendentiously clear shifts to the increase in the frequency of preterm birth between 34–37 weeks of pregnancy and intensive care unit. The latter observation can be explained by better diagnosis of threatening fetal conditions and an increase in the frequency of active obstetric tactics, which in turn affects the number of premature infants, the involvement of the neonatal service, and thus the intensification of the load on intensive. Conclusions. Adequate enhanced monitoring should combine ultrasound, cardiotocography, actography and laboratory techniques, each of which will have a clearly defined purpose in a combined approach to fetal assessment.

A narrative review of in utero gene therapy: advances, challenges, and future considerations

The field of in utero gene therapy (IUGT) represents a crossroad of technologic advancements and medical ethical boundaries. Several strategies have been developed for IUGT focusing on either modifying endogenous genes, replacing missing genes, or modifying gene transcription products. The list of candidate diseases such as hemoglobinopathies, cystic fibrosis, lysosomal storage disorders continues to grow with new strategies being developed as our understanding of their respective underlying molecular pathogenesis increases. Treatment in utero has several distinct advantages to postnatal treatment. Biologic and physiologic phenomena enable the delivery of a higher effective dose, generation of immune tolerance, and the prevention of phenotypic onset for genetic diseases. Therapeutic technology for IUGT including CRISPR-Cas9 systems, zinc finger nucleases (ZFN), and peptide nucleic acids (PNAs) has already shown promise in animal models and early postnatal clinical trials. While the ability to detect fetal diagnoses has dramatically improved with developments in ultrasound and next-generation sequencing, treatment options remain experimental, with several translational gaps remaining prior to implementation in the clinical realm. Complicating this issue, the potential diseases targeted by this approach are often debilitating and would otherwise prove fatal if not treated in some manner. The leap from small animals to large animals, and subsequently, to humans will require further vigorous testing of safety and efficacy.

Prenatal Exome Sequencing: Background, Current Practice and Future Perspectives-A Systematic Review

The introduction of Next Generation Sequencing (NGS) technologies has exerted a significant impact on prenatal diagnosis. Prenatal Exome Sequencing (pES) is performed with increasing frequency in fetuses with structural anomalies and negative chromosomal analysis. The actual diagnostic value varies extensively, and the role of incidental/secondary or inconclusive findings and negative results has not been fully ascertained. We performed a systematic literature review to evaluate the diagnostic yield, as well as inconclusive and negative-result rates of pES. Papers were divided in two groups. The former includes fetuses presenting structural anomalies, regardless the involved organ; the latter focuses on specific class anomalies. Available findings on non-informative or negative results were gathered as well. In the first group, the weighted average diagnostic yield resulted 19%, and inconclusive finding rate 12%. In the second group, the percentages were extremely variable due to differences in sample sizes and inclusion criteria, which constitute major determinants of pES efficiency. Diagnostic pES availability and its application have a pivotal role in prenatal diagnosis, though more homogeneity in access criteria and a consensus on clinical management of controversial information management is envisageable to reach widespread use in the near future.

Unusual Longevity of Edwards Syndrome: A Case Report

BACKGROUND

Trisomy 18, also known as Edwards syndrome, was first described in the 1960s and is now defined as the second most common trisomy. While this genetic disease has been attributed to nondisjunction during meiosis, the exact mechanism remains unknown. Trisomy 18 is associated with a significantly increased mortality rate of about 5-10% of patients surviving until 1 year of age. We present a case of a 26-year-old female diagnosed with trisomy 18, well outliving her life expectancy, maintaining a stable state of health.

CASE PRESENTATION

A 26-year-old female with non-mosaic Edwards syndrome presented to the clinic for follow up after recent hospitalization for aspiration pneumonia. The definitive diagnosis of trisomy 18 was made prenatally utilizing chromosomal analysis and G-banding and fluorescence in situ hybridization (FISH) on cells obtained via amniocentesis. Her past medical history is characterized by severe growth and intellectual limitations; recurrent history of infections, especially respiratory system infections; and a ventricular septal defect (VSD) that was never surgically repaired. She remains in good, stable health and is under close follow-up and monitoring.

CONCLUSIONS

Despite the fact that Edwards syndrome carries a significantly high mortality rate due to several comorbidities, recent literature including this case report has identified patients surviving into adulthood. Advancements in early detection and parent education have likely allowed for these findings. We aim to present a case of an adult with trisomy 18, living in stable condition, with an importance on medical follow-up.

First trimester screening for aneuploidy: may combined test and fetal DNA work together?

INTRODUCTION

The purpose of the study was to evaluate the screening performance of combined test (based on the measurement of nuchal translucency, pregnancy-associated plasma protein A, free β-human chorionic gonadotropin, and maternal age) and fetal DNA screening (NIPS) for trisomies 21 (T21), 18 (T18), and 13 (T13).

MATERIAL AND METHODS

Women who accepted screening had a first-trimester combined test (pregnancy-associated plasma protein A, free β-human chorionic gonadotropin, nuchal translucency interpreted with maternal age) and fetal DNA.

RESULTS

Among 302 women screened (including 4 with affected pregnancies), our study demonstrated that DNA screening for trisomies 21, 18, and 13 achieved a detection rate of 100% with a false-positive rate of 0.02%, overcoming the traditional combined test with 75% of sensitivity and 4.7% of false-positive rate. In particular, fetal DNA may be useful in case of intermediate risk, in order to avoid invasive diagnostic procedures such villocentesis and amniocentesis. Because of fetal DNA costs, it can be used in clinical practice as a second step screening in case of intermediate or high risk at combined test.

CONCLUSION

Fetal DNA screening may be successfully implemented in routine care, achieving a high detection rate, low false-positive rate, and, consequently, greater safety with fewer invasive diagnostic tests than other methods of screening.

Benefits and limitations of noninvasive prenatal aneuploidy screening

The introduction of noninvasive prenatal screening (NIPS) using cell-free DNA (cfDNA) is the newest option for aneuploidy screening during pregnancy. Compared with other aneuploidy screening options, NIPS offers a higher detection rate for trisomy 21 with a low false-positive rate. However, pretest and post-test patient counseling is essential and should include a discussion of the benefits and limitations, the screening rather than diagnostic nature of the test, and the association of a test failure with an increased risk of aneuploidy. Refer patients for genetic counseling when appropriate, particularly if test failure occurs due to a low fetal fraction or if maternal mosaicism or malignancy is suspected.

A cross-sectional survey of pregnant women's knowledge of chromosomal aneuploidy and microdeletion and microduplication syndromes

OBJECTIVE

The purpose of this survey is to evaluate the knowledge of Chinese pregnant women about fetal chromosomal aneuploidy and microdeletion and microduplication syndromes, and Non-invasive prenatal testing (NIPT).

STUDY DESIGN

Written questionnaires were distributed to pregnant women who visited the fetal medicine clinic of the third affiliated hospital of Guangzhou medical university. A total of 330 questionnaires were given. Twenty-two questionnaires with incomplete information were excluded from further analysis. The remaining 308 cases were incorporated into the final analysis. Data were analyzed using IBM SPSS Statistics 26. Comparisons between categorical variables were tested by the use of crosstabs and χ 2 test.

RESULTS

Among pregnant women, the recognition of Down syndrome was the highest (93.5 %), followed by maternal serum screening (74.0 %) and NIPT (69.2 %) for chromosomal aneuploidy. The awareness rates of chromosomal microdeletions and microduplications (18.2 %) and monogenic disorders (13.3 %) were the lowest. There were no significant differences in age, education, and conception way between pregnant women (P > 0.05). When asked the opinion on increasing the testing range of NIPT, more than 50 % of pregnant women chose to follow the provider's advice.

CONCLUSION

More than half of pregnant women lacked knowledge of screening methods for fetal chromosomal abnormalities. Less than 20 % of pregnant women knew microdeletion microduplication syndromes. To enhance the understanding of chromosomal abnormalities can ensure that women can actively choose tests rather than passively agreeing to their provider's recommendations so as to avoid missing the optimal prenatal screening time.

The effect of maternal body mass index and gestational age on circulating trophoblast yield in cell-based noninvasive prenatal testing

OBJECTIVE

To examine the effects of maternal body mass index (BMI) and gestational age (GA) on the number of single circulating trophoblasts (SCT).

METHODS

Maternal blood was collected in 20 to 40 mL. All singleton pregnant women at any gestation were recruited. Trophoblasts were recovered by immunomagnetic enrichment and stained for cytokeratin and CD45. Candidate trophoblasts were identified by fluorescence microscopy.

RESULTS

Blood samples were collected from 425 singleton pregnancies from April 2018 to December 2019. At least one candidate cell was identified in 88% (373/425). There was an inverse correlation between trophoblasts yield and increasing BMI (r = -0.19, P < .001). The mean ± SD number of trophoblasts/mL was 0.12  ± 0.22 in the underweight group (n = 5), 0.23 ± 0.25 in the normal weight (n = 169), 0.18 ± 0.19 in the overweight (n = 114), and 0.13 ± 0.15 in the obese (n = 109). Significantly more cells were identified in the normal weight than those in the obese (P = .001). In addition, the mean ± SD number of cells/mL was 0.21  ± 0.21 at GA of 10 to 14 weeks (n = 260), 0.14 ± 0.23 at GA ≥15 (n = 102) and 0.12 ± 0.12 at GA <10 (n = 63); P < .001.

CONCLUSION

The lower number of SCT was identified from the samples of women with a high BMI. Cell recovery for SCT testing seems optimal at GA of 10 to 14 weeks, but earlier and later testing is still possible.

Use of sound-elicited fetal heart rate accelerations to assess fetal hearing in the second and third trimester

OBJECTIVES

We previously reported that fetal heart rate (FHR) accelerations could be obtained after fetal sound stimulation. We examined FHR accelerations during 20-37 weeks gestational age (GA) in order to assess the optimal time for the test.

METHODS

The fetus was stimulated from the maternal abdomen with pure tone 2000 Hz, 90 dB, 5 s. Changes in the FHR before and after the sound stimulation were measured by a cardiotocometer.

RESULTS

Compared with the positive rate of FHR accelerations at 20-21 weeks GA, significant increases were recognized in 26-27, 28 to 29, 30 to 31, and 34-35 weeks GA. Comparing the positive rate of FHR accelerations between the minimal and moderate variability of FHR baseline, no significant differences were observed at 20-27 weeks GA. On the other hand, at 28-37 weeks GA, the positive rate to detect FHR accelerations due to sound stimulation was 100% in moderate FHR baseline variability.

CONCLUSION

Considering development of human fetal hearing, the method should be performed between 28 and 37 weeks GA and during moderate FHR variability corresponding to active sleep conditions. The method developed in the present study may provide a promising tool for evaluating the fetal hearing.

The decline of amniocentesis and the increase of chorionic villus sampling in modern perinatal medicine

Objective The aims of this study were to determine the rate of change by type of diagnosis by transabdominal chorionic villus sampling (TA-CVS) vs. amniocentesis for aneuploidy and to describe a successful and intensive international training program for TA-CVS in ongoing pregnancies. Methods We conducted a retrospective cohort study of all deliveries from 2010 to 2018 in Sardinia. All invasive diagnostic procedures are conducted at a single regional perinatal referral center. Descriptive statistics were used to compare data across groups, and inter-correlations between variables were investigated by Pearson's correlation coefficient. We subsequently describe the international trainee experiences in TA-CVS over a 35-year period. Results A total of 101,025 deliveries occurred over 9 years. The number of deliveries (13,413-9143, P < 0.0001) and total invasive diagnostic procedures (1506-858 per year, P = 0.019) declined over this period. The percentage of deliveries undergoing invasive diagnostic procedures remained steady (mean: 12.2%). In 2010, TA-CVS made up 32.3% of all invasive diagnostic procedures, while amniocentesis made up 67.7%. By 2018, TA-CVS made up 61.3% of the invasive diagnostic procedures, and amniocentesis, only 38.7%. The rate of TA-CVS increased over 9 years, while the rate of amniocentesis declined. A total of 236 trainees from 39 different countries and 5 different continents rotated through this site. The average length of stay was 2.4 weeks. Conclusion We demonstrate an increasing prevalence of TA-CVS vs. amniocentesis in the current era of prenatal testing and underscore the importance of continuing to train specialists skilled in TA-CVS. Our global operative experience is feasible and sustainable and will have a lasting impact on physicians conducting invasive fetal procedures.

Undiagnosed and Rare Diseases in Perinatal Medicine: Lessons in Context and Cognitive Diagnostic Error

Critically ill neonates experience high rates of morbidity and mortality. Major diagnostic errors are identified in up to 20% of autopsied neonatal intensive care unit deaths. Neonates with undiagnosed or rare congenital disorders may mimic critically ill neonates with more common acquired conditions. The context of the diagnostic evaluation can introduce unique biases that increase the likelihood of diagnostic error. Herein is presented a framework for understanding diagnostic errors in perinatal medicine, and individual, team, and systems-based solutions for improving diagnosis learned through the implementation and administration of an undiagnosed and rare disease program.

Evaluation of host-based molecular markers for the early detection of human sepsis

We have identified 24 molecular markers, based on circulating nucleic acids (CNA) originating from the human genome, which in combination can be used in a quantitative real-time PCR (qPCR) assay to identify the presence of human sepsis, starting two to three days before the first clinical signs develop and including patients who meet the SEPSIS-3 criteria. The accuracy was more than 87 % inside of the same patient cohort for which the markers were developed and up to 81 % in blind studies of patient cohorts which were not included in the marker development. As our markers are host-based, they can be used to capture bacterial as well as fungal sepsis, unlike the current PCR-based tests, which require species-specific primer sets for each organism causing human sepsis. Our assay directly uses an aliquot of cell-free blood as the substrate for the PCR reaction, thus allowing to obtain the diagnostic results in three to four hours after the collection of the blood samples.

Shared decision aids in pregnancy care: A scoping review

BACKGROUND

Shared decision making in pregnancy, labour, and birth is vital to woman-centred care and despite strong evidence for the effectiveness of shared decision making in pregnancy care, practical uptake has been slow.

DESIGN AND AIM

This scoping review aimed to identify and describe effective and appropriate shared decision aids designed to be provided to women in the antenatal period to assist them in making informed decisions for both pregnancy and birth. Two questions guided the enquiry: (i) what shared decision aids for pregnancy and perinatal care are of appropriate quality and feasibility for application in Australia? (ii) which of these decision aids have been shown to be effective and appropriate for Aboriginal and Torres Strait Islander peoples, culturally diverse women, or those with low literacy?

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for scoping reviews (PRISMA-ScR) was used to conduct the review. Five key databases and selected grey literature sources were examined. English language evidence from Australia, Europe, Canada, United Kingdom, New Zealand, and United States of America produced from 2009 was eligible for inclusion, checked against apriori inclusion criteria, and assessed for quality and usability using the International Patient Decision Aid Standards.

RESULTS

From a total of 5,209 search results, 35 sources of evidence reporting on 27 decision aids were included following title/abstract and full-text review. Most of the decision aids concerned decisions around birth (52%, n = 14) or antenatal screening 37% (n = 10). The quality of the decision aids was moderate to high, with most communicating risks, benefits, and choice pathways via a mix of Likert-style scales, quizzes, and pictures or graphs. Use of decision aids resulted in significant reductions in decisional conflict and increased knowledge. The format of decision aids appeared to have no effect on these outcomes, indicating that paper-based are as effective as video- or audio-based decision aids. Eleven decision aids were suitable for low literacy or low health literacy women, and six were either developed for culturally diverse groups or have been translated into other languages. No decision aids found were specific to Aboriginal and Torres Strait Islander peoples.

CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

The 27 decision aids are readily adoptable into westernised healthcare settings and can be used by midwives or multidisciplinary teams in conjunction with women. Decision aids are designed to support women, and families to arrive at informed choices and supplement the decision-making process rather than to replace consumer-healthcare professional interaction. If given before an appointment, high quality decision aids can increase a woman's familiarity with medical terminology, options for care, and an insight into personal values, thereby decreasing decisional conflict and increasing knowledge.

Cell-Free Fetal DNA: A Novel Biomarker for Early Prediction of Pre-eclampsia and Other Obstetric Complications

Hypertensive disorder of pregnancy, especially Pre-eclampsia is one of the major causes of increased maternal and perinatal morbidity and mortality all over the world. Early prediction of pre-eclampsia is the need of modern obstetrics, as this can timely prevent the progress of disease as well as related fetal and maternal morbidity and mortality. In addition to the screening of fetal aneuploidies, Rhesus-D status, fetal sex, single gene disorders, the cell-free fetal Deoxyribonucleic acid (DNA) quantification has emerged as a promising biomarker for the prediction of pre-eclampsia. Hence, its use can help in the early prediction of hypertensive disorders of pregnancy, especially pre-eclampsia even before the appearance of symptoms. Furthermore, in future, it can also help in the determination of the complete DNA sequence of every gene of the fetus. The present review focuses on recent literature concerning the use of cell-free fetal DNA in early prediction of preeclampsia as well as for non-invasive prenatal genetic screening of fetus for various disorders. Methods: The recent literature related to cell-free fetal DNA was searched from numerous English language journals and published peer-reviewed articles on Pubmed, Google Scholar, MEDLINE and various government agencies till 2016.

What you need to know about maternal-fetal medicine

The field of pediatric Surgery now encompasses fetal Surgery. The purpose of this article is to review aspects of antepartum care pertinent to the fetal and pediatric surgeon. We summarize antepartum screening, methods to assess the fetus, gestational disorders and variants of umbilical cord insertion sites and the placenta.

Prenatally diagnosed developmental abnormalities of the central nervous system and genetic syndromes: A practical review

Developmental brain abnormalities are complex and can be difficult to diagnose by prenatal imaging because of the ongoing growth and development of the brain throughout pregnancy and the limitations of ultrasound, often requiring fetal magnetic resonance imaging as an additional tool. As for all major structural congenital anomalies, amniocentesis with chromosomal microarray and a karyotype is the first-line recommended test for the genetic work-up of prenatally diagnosed central nervous system (CNS) abnormalities. Many CNS defects, especially neuronal migration defects affecting the cerebral and cerebellar cortex, are caused by single-gene mutations in a large number of different genes. Early data suggest that prenatal diagnostic exome sequencing for fetal CNS defects will have a high diagnostic yield, but interpretation of sequencing results can be complex. Yet a genetic diagnosis is important for prognosis prediction and recurrence risk counseling. The evaluation and management of such patients is best done in a multidisciplinary team approach. Here, we review general principles of the genetic work-up for fetuses with CNS defects and review categories of genetic causes of prenatally diagnosed CNS phenotypes.

Noninvasive prenatal testing: the aspects of its introduction into clinical practice

The last couple of years have witnessed the rapid development of prenatal molecular-based screening for fetal aneuploidies that utilizes the analysis of cell-free DNA circulating in the bloodstream of a pregnant woman. The present review looks at the potential and limitations of such testing and the possible causes of false-positive and false-negative results. The review also describes the underlying principles of data acquisition and analysis the testing involves. In addition, we talk about the opinions held by the expert community and some aspects of legislation on the use of noninvasive prenatal testing (NIPT) in clinical practice in the countries where NIPT is much more widespread than in Russia.

Combined use of bacterial artificial chromosomes-on-beads with karyotype detection improves prenatal diagnosis

Background

This study evaluated the individual and combined diagnostic performance of the bacterial artificial chromosomes (BACs)-on-Beads (BoBs™) assay and conventional karyotyping for the prenatal detection of chromosomal abnormalities in pregnant women who were 35 or more years-old.

Method

The primary outcome was concordance of any numerical, structural, or submicroscopic chromosomal abnormalities between BoBs™ and conventional karyotyping of amniotic fluid specimens from pregnant women at 17 to 22 weeks gestation.

Results

We examined samples from 4852 pregnant women. BoBs™ indicated that 4708 samples were normal (97.03%), and 144 were abnormal (2.97%); conventional karyotyping indicated that 4656 (95.96%) samples were normal and 196 (4.04%) were abnormal. The combined use of both methods indicated that 4633 of 4852 samples were normal (95.49%) and 219 of 4852 samples (4.51%) were abnormal. The kappa coefficient of the combined test was 0.70, indicating substantial consistency between BoBs™ and conventional karyotyping (95% CI = 0.65–0.76, P < 0.001).

Conclusions

Our results indicate that the combined use of BoBs™ and conventional karyotyping detected more fetal abnormalities than either test alone.

A Reappraisal of Circulating Fetal Cell Noninvasive Prenatal Testing

New tools for higher-resolution fetal genome analysis including microarray and next-generation sequencing have revolutionized prenatal screening. This article provides commentary on this rapidly advancing field and a future perspective emphasizing circulating fetal cell (CFC) utility. Despite the tremendous technological challenges associated with their reliable and cost-effective isolation from maternal blood, CFCs have a strong potential to bridge the gap between the diagnostic sensitivity of invasive procedures and the desirable noninvasive nature of cell-free fetal DNA (cffDNA). Considering the rapid advances in both rare cell isolation and low-input DNA analysis, we argue here that CFC-based noninvasive prenatal testing is poised to be implemented clinically in the near future.

Noninvasive Prenatal Diagnosis of Single-Gene Disorders by Use of Droplet Digital PCR

BACKGROUND

Prenatal diagnosis in pregnancies at risk of single-gene disorders is currently performed using invasive methods such as chorionic villus sampling and amniocentesis. This is in contrast with screening for common aneuploidies, for which noninvasive methods with a single maternal blood sample have become standard clinical practice.

METHODS

We developed a protocol for noninvasive prenatal diagnosis of inherited single-gene disorders using droplet digital PCR from circulating cell-free DNA (cfDNA) in maternal plasma. First, the amount of cfDNA and fetal fraction is determined using a panel of TaqMan assays targeting high-variability single-nucleotide polymorphisms. Second, the ratio of healthy and diseased alleles in maternal plasma is quantified using TaqMan assays targeting the mutations carried by the parents. Two validation approaches of the mutation assay are presented.

RESULTS

We collected blood samples from 9 pregnancies at risk for different single-gene disorders, including common conditions and rare metabolic disorders. We measured cases at risk of hemophilia, ornithine transcarbamylase deficiency, cystic fibrosis, β-thalassemia, mevalonate kinase deficiency, acetylcholine receptor deficiency, and DFNB1 nonsyndromic hearing loss. We correctly differentiated affected and unaffected pregnancies (2 affected, 7 unaffected), confirmed by neonatal testing. We successfully measured an affected pregnancy as early as week 11 and with a fetal fraction as low as 3.7% (0.3).

CONCLUSIONS

Our method detects single-nucleotide mutations of autosomal recessive diseases as early as the first trimester of pregnancy. This is of importance for metabolic disorders in which early diagnosis can affect management of the disease and reduce complications and anxiety related to invasive testing.

Interpretations of autonomous decision-making in antenatal genetic screening among women in China, Hong Kong and Pakistan

The concept of informed choice for antenatal screening consists of Western ideologies, encapsulating individualistic approaches, and may be valued differently by people from countries with more collectivist cultures. This study aimed to explore perceptions of informed choice in antenatal screening in women from China, Hong Kong and Pakistan. A Q-methodology study was conducted during June 2016 to February 2017, in China (Shanghai and Duyun), Hong Kong and Pakistan (Lahore). A total of 299 women rank ordered 41 statements. Following by-person factor analysis, five distinct viewpoints were identified: choice as a maternal responsibility entrusted to doctors; choice as a shared decision led by the mother; choice as a shared decision led by the partner; choice as a responsibility delegated to the partner and doctors; and choice within a religious discourse. The findings highlight ethical dilemmas for healthcare professionals in facilitating informed choice for antenatal screening where policy and practice guidelines adapt predominantly individualistic approaches. Women's preferences for decision-making with health professionals and/or their partner, with minimal emphasis on individual rights, suggest the need for clarification of the role of health professionals in supporting and facilitating decision-making to enhance women's autonomy. Policy and practice guidelines need to be (re)framed to facilitate decision-making processes for antenatal screening using relational approaches to autonomy.

Recent developments in genetics and medically assisted reproduction: from research to clinical applications

Two leading European professional societies, the European Society of Human Genetics and the European Society for Human Reproduction and Embryology, have worked together since 2004 to evaluate the impact of fast research advances at the interface of assisted reproduction and genetics, including their application into clinical practice. In September 2016, the expert panel met for the third time. The topics discussed highlighted important issues covering the impacts of expanded carrier screening, direct-to-consumer genetic testing, voiding of the presumed anonymity of gamete donors by advanced genetic testing, advances in the research of genetic causes underlying male and female infertility, utilisation of massively parallel sequencing in preimplantation genetic testing and non-invasive prenatal screening, mitochondrial replacement in human oocytes, and additionally, issues related to cross-generational epigenetic inheritance following IVF and germline genome editing. The resulting paper represents a consensus of both professional societies involved.

Promises, pitfalls and practicalities of prenatal whole exome sequencing

Prenatal genetic diagnosis provides information for pregnancy and perinatal decision-making and management. In several small series, prenatal whole exome sequencing (WES) approaches have identified genetic diagnoses when conventional tests (karyotype and microarray) were not diagnostic. Here, we review published prenatal WES studies and recent conference abstracts. Thirty-one studies were identified, with diagnostic rates in series of five or more fetuses varying between 6.2% and 80%. Differences in inclusion criteria and trio versus singleton approaches to sequencing largely account for the wide range of diagnostic rates. The data suggest that diagnostic yields will be greater in fetuses with multiple anomalies or in cases preselected following genetic review. Beyond its ability to improve diagnostic rates, we explore the potential of WES to improve understanding of prenatal presentations of genetic disorders and lethal fetal syndromes. We discuss prenatal phenotyping limitations, counselling challenges regarding variants of uncertain significance, incidental and secondary findings, and technical problems in WES. We review the practical, ethical, social and economic issues that must be considered before prenatal WES could become part of routine testing. Finally, we reflect upon the potential future of prenatal genetic diagnosis, including a move towards whole genome sequencing and non-invasive whole exome and whole genome testing. © 2017 John Wiley & Sons, Ltd.

Recent developments in genetics and medically-assisted reproduction: from research to clinical applications†‡

Two leading European professional societies, the European Society of Human Genetics and the European Society for Human Reproduction and Embryology, have worked together since 2004 to evaluate the impact of fast research advances at the interface of assisted reproduction and genetics, including their application into clinical practice. In September 2016, the expert panel met for the third time. The topics discussed highlighted important issues covering the impacts of expanded carrier screening, direct-to-consumer genetic testing, voiding of the presumed anonymity of gamete donors by advanced genetic testing, advances in the research of genetic causes underlying male and female infertility, utilisation of massively-parallel sequencing in preimplantation genetic testing and non-invasive prenatal screening, mitochondrial replacement in human oocytes, and additionally, issues related to cross-generational epigenetic inheritance following IVF and germline genome editing. The resulting paper represents a consensus of both professional societies involved.

Medical genetics and genomic medicine in the United States. Part 2: Reproductive genetics, newborn screening, genetic counseling, training, and registries

Review of genetics in the United States with emphasis on the prenatal, metabolic, genetic counseling, and training aspects of the field.

Liquid Biopsy: From Basic Research to Clinical Practice

Liquid biopsy refers to the molecular analysis in biological fluids of nucleic acids, subcellular structures, especially exosomes, and, in the context of cancer, circulating tumor cells. In the last 10 years, there has been an intensive research in liquid biopsy to achieve a less invasive and more precise personalized medicine. Molecular assessment of these circulating biomarkers can complement or even surrogate tissue biopsy. Because of this research, liquid biopsy has been introduced in clinical practice, especially in oncology, prenatal screening, and transplantation. Here we review the biology, methodological approaches, and clinical applications of the main biomarkers involved in liquid biopsy.

[Training of residents in amniocentesis: Effectiveness of a craft simulator]

OBJECTIVE

This prospective study aims to assess a low fidelity simulation device for learning amniocentesis to gynecology-obstetrics residents.

METHODS

From 2013 to 2016, gynecology-obstetrics residents of all levels, from the maternity of Nancy hospital, which have already performed amniocentesis or not, participated in amniocentesis training on an artisanal simulator. Residents were evaluated on the amniocentesis simulator according to seven quality criteria. Three scores were assigned: the first (S1) at the beginning of the first training session, the second (S2) at the end of the first session after individualized personal training and the third (S3) two months after the first simulation.

RESULTS

A total of 40 residents were included. The scores obtained by the residents were 3.2±1.8 points for S1 versus 6.2±0.9 points for S2 (P<0.001). Two months after, the residents' performances remained significantly improved compared to the initial assessment with a score (S3) of 5.8±1.3 points at S3 (P<0.001).

CONCLUSION

Amniocentesis craft simulator is effective for performance improvement and allows a persistence of acquired skills two months after the training. At the time of "never the first time on the patient", it should be part of the curriculum of gynecology-obstetrics residents in order to guarantee patients quality care and optimum safety.