Parental motivations for and adaptation to trio-exome sequencing in a prospective prenatal testing cohort: Beyond the diagnosis

Incremental yield of prenatal exome sequencing in fetuses with skeletal system abnormalities: A systematic review and meta-analysis

INTRODUCTION

Fetal skeletal abnormalities can be caused by various factors and genetic cause plays an important role. Prenatal exome sequencing (ES) has been shown to be a powerful approach for accurate prenatal molecular diagnoses. Diagnostic yield of ES in fetal skeletal abnormalities varies significantly across studies. This study aimed to perform a systematic review of the literature and meta-analysis to assess the incremental yield of ES in fetuses with different kinds of skeletal abnormalities and a negative result on chromosome microarray or karyotyping.

MATERIAL AND METHODS

The PubMed, Embase, Web of Science, and Cochrane Library databases were systematically searched up to November 26, 2022. Relevant data were collected from observational studies containing five or more cases of skeletal abnormalities who underwent ES. The incremental yield of ES was evaluated by single proportion analysis and 95% confidence interval (CI), both according to the article features and individual phenotypes. This study was registered on PROSPERO as CRD42022382800.

RESULTS

Twenty-six studies including 524 individuals met the inclusion criteria. The pooled incremental yield was 60.2% (95% CI, 53.4%-66.9%) for all fetuses with skeletal abnormalities. In subgroup analysis, the additional diagnostic yield was 83.9% (95% CI, 76.4%-90.4%) in isolated dysplasia cases (group I), 52.0% (95% CI, 32.9%-70.9%) in dysplasia with non-skeletal abnormalities cases (group II), 33.3% (95% CI, 19.3%-48.6%) in isolate dysostoses cases (group III), 47.8% (95 % CI, 35.8%-60.0%) in dysostoses with non-skeletal abnormalities cases (group IV), 83.0% (95% CI, 63.7%-97.1%) in combination of the two phenotypes without non-skeletal abnormalities cases (group V), 74.5% (95% CI, 54.9%-90.9%) in combination of the two phenotypes with non-skeletal abnormalities cases (group VI). The origin of the pathogenic variations differed among the groups. Most causative variants were de novo in groups I (97/133, 72.9%), V (14/23, 60.9%), and VI (15/26, 57.7%). Meanwhile, pathogenic variations in III (18/25, 72.0%) and IV (37/67, 55.2%) were more often inherited from a parent.

CONCLUSIONS

ES had a favorable incremental yield in fetuses with skeletal abnormalities. The common pathogenic variations and genetic patterns of skeletal abnormalities vary among different subtypes. Interpreting this difference is beneficial for personalized clinical consultation.

Beyond the Diagnosis: Valuing Genome-Wide Sequencing for Rare Disease Diagnosis Using Contingent Valuation

BACKGROUND AND OBJECTIVE

The utility of genome-wide sequencing is often quantified in terms of its diagnostic yield. Although obtaining a diagnosis is a fundamental aspect of value, service users also value broader clinical, informational, process and psychological factors in the provision of genomic testing. This study aims to value genome-wide sequencing from the user perspective in Scotland.

METHODS

A survey was developed and administered to 1014 patients and families with experience of genome-wide sequencing to diagnose a rare condition in Scotland. Participants' willingness to pay for genomic testing was elicited using a contingent valuation payment card. The survey included two genomic-related patient-reported outcome measures: (i) the Personal Utility Scale (PrU) to generate scores for the personal utility of genome-wide sequencing; and (ii) a subscale of the Feelings About Genomic Testing Results (FACTOR) questionnaire to measure negative psychological outcomes. Data were also collected on participants' prior experiences of genomic testing services. A double-hurdle regression model investigated the predictors of patients' willingness to pay for genomic testing.

RESULTS

Of the 1014 invitations sent, 171 contingent valuation questionnaires were returned. Diagnosed participants reported higher personal utility on PrU than undiagnosed participants. However, both groups reported similar negative psychological outcomes on FACTOR. Diagnosed participants were willing to pay £2043 for genome-wide sequencing, compared with £835 for undiagnosed participants. Diagnostic status, waiting time for results and FACTOR scores (negative psychological outcomes) influenced users' valuations of genome-wide sequencing.

CONCLUSIONS

Obtaining a diagnosis is a fundamental component of utility in the provision of genomic testing. However, there is still value to those who do not receive a diagnosis. These results have implications for service delivery, such as providing targeted pre-test and post-test genetic counselling, and investing in efficient genome sequencing pipelines to reduce waiting times. Valuing the user experience of genomic testing aligns with patient-centred approaches to the provision of healthcare.

Equity and timeliness as factors in the effectiveness of an ethical prenatal sequencing service: reflections from parents and professionals

Prenatal sequencing tests are being introduced into clinical practice in many developed countries. In part due to its greater ability to detect genetic variation, offering prenatal sequencing can present ethical challenges. Here we review ethical issues arising following the implementation of prenatal sequencing in the English National Health Service (NHS). We analysed semi structured interviews conducted with 48 parents offered prenatal sequencing and 63 health professionals involved in delivering the service to identify the ethical issues raised. Two main themes were identified: (1) Equity of access (including issues around eligibility criteria, laboratory analytical processes, awareness and education of clinicians, fear of litigation, geography, parental travel costs, and access to private healthcare), and (2) Timeliness and its impact on parental decision-making in pregnancy (in the context of the law around termination of pregnancy, decision-making in the absence of prenatal sequencing results, and the "importance" of prenatal sequencing results). Recognising both the practical and systemic ethical issues that arise out of delivering a national prenatal sequencing service is crucial. Although specific to the English context, many of the issues we identified are applicable to prenatal sequencing services more broadly. Education of health professionals and parents will help to mitigate some of these ethical issues.

'Something that helped the whole picture': Experiences of parents offered rapid prenatal exome sequencing in routine clinical care in the English National Health Service

OBJECTIVES

In October 2020, rapid prenatal exome sequencing (pES) was introduced into routine National Health Service (NHS) care in England. This study aimed to explore parent experiences and their information and support needs from the perspective of parents offered pES and of health professionals involved in its delivery.

METHODS

In this qualitative study, semi-structured interviews were conducted with 42 women and 6 male partners and 63 fetal medicine and genetic health professionals. Interviews were transcribed verbatim and analysed using thematic analysis.

RESULTS

Overall views about pES were positive and parents were grateful to be offered the test. Highlighted benefits of pES included the value of the additional information for pregnancy management and planning for future pregnancies. An anxious wait for results was common, often associated with the need to make decisions near to 24 weeks in pregnancy when there are legal restrictions for late termination. Descriptions of dealing with uncertainty were also common, even when results had been returned. Many parents described pES results as informing decision-making around whether or not to terminate pregnancy. Some professionals were concerned that a non-informative result could be overly reassuring and highlighted that careful counselling was needed to ensure parents have a good understanding of what the result means for their pregnancy. Emotional support from professionals was valued; however, some parents felt that post-test support was lacking.

CONCLUSION

Parents and professionals welcomed the introduction of pES. Results inform parents' decision-making around the termination of pregnancy. When there are no diagnostic findings or uncertain findings from pES, personalised counselling that considers scans and other tests are crucial. Directing parents to reliable online sources of information and providing emotional support throughout could improve their experiences of care.

Access to prenatal exome sequencing for fetal malformations: A qualitative landscape analysis in the US

OBJECTIVE

There is increasing evidence supporting the clinical utility of next generation sequencing for identifying fetal genetic disorders. However, there are limited data on the demand for and accessibility of these tests, as well as payer coverage in the prenatal context. We sought to identify clinician perspectives on the utility of prenatal exome sequencing (ES) and on equitable access to genomic technologies for the care of pregnancies complicated by fetal structural anomalies.

METHOD

We conducted two focus group discussions and six interviews with a total of 13 clinicians (11 genetic counselors; 2 Maternal Fetal Medicine/Geneticists) from U.S. academic centers and community clinics.

RESULTS

Participants strongly supported ES for prenatal diagnostic testing in pregnancies with fetal structural anomalies. Participants emphasized the value of prenatal ES as an opportunity for a continuum of care before, during, and after a pregnancy, not solely as informing decisions about abortions. Cost and coverage of the test was the main access barrier, and research was the main pathway to access ES in academic centers.

CONCLUSION

Further integrating the perspectives of additional key stakeholders are important for understanding clinical utility, developing policies and practices to address access barriers, and assuring equitable provision of prenatal diagnostic testing.

Piloting a multidisciplinary approach to improve outcomes of fetal whole exome sequencing: An overview of workflow and case example

INTRODUCTION

Whole exome sequencing (WES) has increasingly become integrated into prenatal care and genetic testing pathways. Current studies of prenatal WES have focused on diagnostic yield. The possibility of obtaining a variant of uncertain significance and lack of provider expertise are frequently described as common barriers to clinical integration of prenatal WES. We describe the implementation and workflow for a multidisciplinary approach to effectively integrate prenatal WES into maternal-fetal care to overcome these barriers.

METHODS

A multidisciplinary team reviews and approves potential cases for WES. This team reviews WES results, reclassifying variants as appropriate and provides recommendations for postnatal care. A detailed description of this workflow is provided, and a case example is included to demonstrate effectiveness of this approach. Our team has approved 62 cases for WES with 45 patients ultimately pursuing WES. We have achieved a diagnostic yield of 40% and the multidisciplinary team has played a role in variant interpretation in 50% of the reported variants of uncertain significance.

CONCLUSIONS

This approach facilitates communication between prenatal and postnatal care teams and provides accurate interpretation and recommendations for identified fetal variants. This model can be replicated to ensure appropriate patient care and effective integration of novel genomic technologies into prenatal settings.

Information is power: The experiences, attitudes and needs of individuals who chose to have prenatal genomic sequencing for fetal anomalies

OBJECTIVE

This study sought to evaluate the experiences of individuals who chose to participate in a study and receive prenatal genomic sequencing (pGS) for fetuses with congenital structural anomalies.

METHOD

Individuals who received research results of prenatal sequencing were invited to participate in semi-structured interviews about their experiences. A constructivist grounded theory approach was used to code and analyze interviews.

RESULTS

Thirty-three participants from 27 pregnancies were interviewed. Participants were motivated to enroll in the study to find out more about their fetus' condition and prepare for the future. The waiting period was a time of significant anxiety for participants. Most participants felt relief and closure upon receiving results, regardless of the category of result, and had a clear understanding of the implications of the results.

CONCLUSION

Participants' experiences with pGS were often intertwined with the experience of having a fetus with an abnormality. Participants were satisfied with the decision to participate in research and the support they received from the healthcare team, although waiting for results was associated with anxiety. The healthcare team plays an integral role in setting expectations and validating feelings of anxiety, fear and uncertainty.

Implementing a rapid fetal exome sequencing service: What do parents and health professionals think?

OBJECTIVES

Prenatal exome sequencing (pES) for the diagnosis of fetal abnormalities is being introduced more widely in clinical practice. Here we explore parents' and professionals' views and experiences of pES, to identify perceived benefits, concerns, and support needs.

METHODS

Semi-structured interviews were conducted with 11 parents and 20 health professionals (fetal medicine and clinical genetics) with experience of rapid pES prior to implementation in the English National Health Service. Interviews were transcribed verbatim and analysed thematically.

RESULTS

Parents and professionals were largely positive about pES, emphasising clinical and psychosocial benefits of a timely, definitive diagnosis in pregnancy. Concerns included parental anxiety related to the timing of pES results or uncertain findings, a need for guidelines for case selection and reporting, and ensuring sufficient capacity for counselling, phenotyping and variant interpretation. Professionals were concerned non-genetics professionals may not be equipped to counsel parents on the complexities of pES.

CONCLUSION

These findings highlight important issues for clinical implementation of pES. Expert counselling is required to enable parents to make informed decisions during a stressful time. To achieve this, professionals need further education and training, and fetal medicine and genetics services must work closely together to ensure parental understanding and appropriate support.

Implementation of Exome Sequencing in Prenatal Diagnosis and Impact on Genetic Counseling: The Polish Experience

Background: Despite advances in routine prenatal cytogenetic testing, most anomalous fetuses remain without a genetic diagnosis. Exome sequencing (ES) is a molecular technique that identifies sequence variants across protein-coding regions and is now increasingly used in clinical practice. Fetal phenotypes differ from postnatal and, therefore, prenatal ES interpretation requires a large amount of data deriving from prenatal testing. The aim of our study was to present initial results of the implementation of ES to prenatal diagnosis in Polish patients and to discuss its possible clinical impact on genetic counseling. Methods: In this study we performed a retrospective review of all fetal samples referred to our laboratory for ES from cooperating centers between January 2017 and June 2021. Results: During the study period 122 fetuses were subjected to ES at our institution. There were 52 abnormal ES results: 31 in the group of fetuses with a single organ system anomaly and 21 in the group of fetuses with multisystem anomalies. The difference between groups was not statistically significant. There were 57 different pathogenic or likely pathogenic variants reported in 33 different genes. The most common were missense variants. In 17 cases the molecular diagnosis had an actual clinical impact on subsequent pregnancies or other family members. Conclusions: Exome sequencing increases the detection rate in fetuses with structural anomalies and improves genetic counseling for both the affected couple and their relatives.