Evaluating the implementation of the rapid prenatal exome sequencing (pES) service in England.

Introduction In October 2020, a national rapid prenatal exome sequencing (pES) service was rolled out across the English National Health Service (NHS). This service is delivered by multiple clinical and two laboratory teams. Whilst there was high level national guidance to support implementation, it was unclear how the service has been delivered in practice.

Parental Somatic Mosaicism Detected During Prenatal Diagnosis.

Objective: Accurate recurrence risks are essential for genomic counselling and parental reproductive choices. Historically, Sanger sequencing was used to test parental samples, which has a limited sensitivity of ∼ 10% for detecting somatic mosaicism. Next generation sequencing (NGS) methods, utilised for non-invasive prenatal diagnosis (NIPD) and trio prenatal exome sequencing in our laboratory, have greater sensitivity.

Implementation of a National Prenatal Exome Sequencing Service in England: Cost-Effectiveness Analysis.

Objective: Prenatal exome sequencing (pES) for diagnosing fetal structural anomalies commenced in the English National Health Service (NHS) in 2020. We evaluated cost-effectiveness to the healthcare system, and costs to families, of pES in addition to standard testing, compared to standard testing alone.

Design: A cost-effectiveness analysis combining costs, outcomes, parent and professional interview and professional survey data.

"I'm quite proud of how we've handled it": health professionals' experiences of returning additional findings from the 100,000 genomes project.

Participants in the 100,000 Genomes Project (100kGP) could consent to receive additional finding (AF) results, individual variants relating to genes associated with susceptibility to cancer and familial hypercholesterolemia (FH). In the study reported here, qualitative interviews were used to explore the experiences of National Health Service (NHS) professionals from across England who were tasked with returning over 80,000 "no AF" results and 700 positive AF results to 100kGP participants. Interviews were conducted with 45 professionals from a range of backgrounds, including Genetic Counsellors, Clinical Geneticists, FH Clinical Nurse Specialists and Clinical Scientists.

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).

Delivery of a national prenatal exome sequencing service in England: a mixed methods study exploring healthcare professionals' views and experiences.

Introduction: In October 2020, rapid prenatal exome sequencing (pES) was introduced into routine National Health Service (NHS) care in England, requiring the coordination of care from specialist genetics, fetal medicine (FM) and laboratory services. This mixed methods study explored the experiences of professionals involved in delivering the pES service during the first 2 years of its delivery in the NHS.

Methods: A survey ( = 159) and semi-structured interviews ( = 63) with healthcare professionals, including clinical geneticists, FM specialists, and clinical scientists (interviews only) were used to address: 1) Views on the pES service; 2) Capacity and resources involved in offering pES; 3) Awareness, knowledge, and educational needs; and 4) Ambitions and goals for the future.

An exploratory open-label multicentre phase I/II trial evaluating the safety and efficacy of postnatal or prenatal and postnatal administration of allogeneic expanded fetal mesenchymal stem cells for the treatment of severe osteogenesis imperfecta in infants and fetuses: the BOOSTB4 trial protocol.

Introduction: Severe osteogenesis imperfecta (OI) is a debilitating disease with no cure or sufficiently effective treatment. Mesenchymal stem cells (MSCs) have good safety profile, show promising effects and can form bone. The Boost Brittle Bones Before Birth (BOOSTB4) trial evaluates administration of allogeneic expanded human first trimester fetal liver MSCs (BOOST cells) for OI type 3 or severe type 4.

Expanding Access to Noninvasive Prenatal Diagnosis for Monogenic Conditions to Consanguineous Families.

Background: Cell-free fetal DNA exists within the maternal bloodstream during pregnancy and provides a means for noninvasive prenatal diagnosis (NIPD). Our accredited clinical service offers definitive NIPD for several autosomal recessive (AR) and X-linked conditions using relative haplotype dosage analysis (RHDO). RHDO involves next-generation sequencing (NGS) of thousands of common single nucleotide polymorphism (SNPs) surrounding the gene of interest in the parents and an affected or unaffected offspring to conduct haplotype phasing of the high- and low-risk alleles.

'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.

Monogenic conditions and central nervous system anomalies: A prospective study, systematic review and meta-analysis.

Objectives: Determine the incremental diagnostic yield of prenatal exome sequencing (pES) over chromosome microarray (CMA) or G-banding karyotype in fetuses with central nervous system (CNS) abnormalities.

Methods: Data were collected via electronic searches from January 2010 to April 2022 in MEDLINE, Cochrane, Web of Science and EMBASE. The NHS England prenatal exome cohort was also included.

Experiences of coordinated care for people in the UK affected by rare diseases: cross-sectional survey of patients, carers, and healthcare professionals.

Background: Poorly coordinated care can have major impacts on patients and families affected by rare conditions, with negative physical health, psychosocial and financial consequences. This study aimed to understand how care is coordinated for rare diseases in the United Kingdom.

Methods: We undertook a national survey in the UK involving 760 adults affected by rare diseases, 446 parents/carers of people affected by rare diseases, and 251 healthcare professionals who care for people affected by rare diseases.

Knowledge, attitudes and decision regret: a longitudinal survey study of participants offered genome sequencing in the 100,000 Genomes Project.

We used cross-sectional surveys to compare the knowledge, attitudes, and decision regret of participants who had consented for genome sequencing (GS) for rare disease diagnosis in the 100,000 Genomes Project (100kGP) across two timepoints (at the time of consenting for GS (T1) and 12-18 months later (T2)). At T1, participants (n = 504) completed a survey that included measures of general knowledge of GS ("Knowledge of Genome Sequencing" (KOGS)), specific knowledge of GS and attitudes towards GS ("General attitudes" and "Specific attitudes"). At T2, participants (n = 296) completed these same assessments (apart from the specific knowledge scale) together with an assessment of decision regret towards GS ("Decisional Regret Scale").

Enhanced mitochondrial genome analysis: bioinformatic and long-read sequencing advances and their diagnostic implications.

Introduction: Primary mitochondrial diseases (PMDs) comprise a large and heterogeneous group of genetic diseases that result from pathogenic variants in either nuclear DNA (nDNA) or mitochondrial DNA (mtDNA). Widespread adoption of next-generation sequencing (NGS) has improved the efficiency and accuracy of mtDNA diagnoses; however, several challenges remain.

Areas Covered: In this review, we briefly summarize the current state of the art in molecular diagnostics for mtDNA and consider the implications of improved whole genome sequencing (WGS), bioinformatic techniques, and the adoption of long-read sequencing, for PMD diagnostics.

Non-invasive fetal genotyping for maternal alleles with droplet digital PCR: A comparative study of analytical approaches.

Objectives: To develop a flexible droplet digital PCR (ddPCR) workflow to perform non-invasive prenatal diagnosis via relative mutation dosage (RMD) for maternal pathogenic variants with a range of inheritance patterns, and to compare the accuracy of multiple analytical approaches.

Methods: Cell free DNA (cfDNA) was tested from 124 archived maternal plasma samples: 88 cases for sickle cell disease and 36 for rare Mendelian conditions. Three analytical methods were compared: sequential probability ratio testing (SPRT), Bayesian and z-score analyses.

Variability in Fetal Fraction Estimation: Comparing Fetal Fractions Reported by Noninvasive Prenatal Testing Providers Globally.

Background: Fetal fraction (FF) measurement is considered important for reliable noninvasive prenatal testing (NIPT). Using minimal FF threshold as a quality parameter is under debate. We evaluated the variability in reported FFs of individual samples between providers and laboratories and within a single laboratory.

Non-invasive prenatal diagnosis (NIPD): how analysis of cell-free DNA in maternal plasma has changed prenatal diagnosis for monogenic disorders.

Cell-free fetal DNA (cffDNA) is released into the maternal circulation from trophoblastic cells during pregnancy, is detectable from 4 weeks and is representative of the entire fetal genome. The presence of this cffDNA in the maternal bloodstream has enabled clinical implementation of non-invasive prenatal diagnosis (NIPD) for monogenic disorders. Detection of paternally inherited and de novo mutations is relatively straightforward, and several methods have been developed for clinical use, including quantitative polymerase chain reaction (qPCR), and PCR followed by restriction enzyme digest (PCR-RED) or next-generation sequencing (NGS).