Exome sequencing in newborns with congenital deafness as a model for genomic newborn screening: the Baby Beyond Hearing project

DNA Sequencing in Newborn Screening: Opportunities, Challenges, and Future Directions

BACKGROUND

Newborn screening is a public health system designed to identify infants at risk for conditions early in life to facilitate timely intervention and treatment to prevent or mitigate adverse health outcomes. Newborn screening programs use tandem mass spectrometry as a platform to detect several treatable inborn errors of metabolism, and the T-cell receptor excision circle assay to detect some inborn errors of the immune system. Recent advancements in DNA sequencing have decreased the cost of sequencing and allow us to consider DNA sequencing as an additional platform to complement other newborn screening methods.

CONTENT

This review provides an overview of DNA-based newborn screening, including its applications, opportunities, challenges, and future directions. We discuss the potential benefits of expanded DNA sequencing in newborn screening, such as expanding conditions screened and improved specificity and sensitivity of currently screened conditions. Additionally, we examine the ethical, legal, and social implications of implementing genomic sequencing in newborn screening programs, including issues related to consent, privacy, equity, data interpretation, scalability, and psychosocial impact on families. Additionally, we explore emerging strategies for addressing current limitations and advancing the field of newborn screening.

SUMMARY

DNA sequencing in newborn screening has the potential to improve the diagnosis and management of rare diseases but also presents significant challenges that need to be addressed before implementation at the population level.

Key informant perspectives on implementing genomic newborn screening: a qualitative study guided by the Action, Actor, Context, Target, Time framework

Newborn screening (NBS) programmes are highly successful, trusted, public health interventions. Genomic sequencing offers the opportunity to increase the benefits of NBS by screening infants for a greater number and variety of childhood-onset conditions. This study aimed to describe who needs to do what, when, and for whom to deliver genomic newborn screening (gNBS) and capture perceived implementation barriers and enablers. 'Key informants' (individuals involved in the delivery of NBS) were interviewed. The Actor, Action, Context, Time and Target framework guided data collection and analysis. Participants (N = 20) identified new Actions required to deliver gNBS (educating healthcare providers, longitudinal psychosocial support), NBS Actions needing modification (obtaining consent) and NBS Actions that could be adopted for gNBS (prompt referral pathways). Obtaining consent in a prenatal Context was a source of some disagreement. The Time to disclose high chance results was raised as a key consideration in gNBS programme design. Genetic counsellors were identified as key Actors in results management, but workforce limitations may be a barrier. Online decision support tools were an enabler to offering gNBS. The implementation of gNBS will require behaviour changes from HCPs delivering NBS. Findings can inform how to deliver gNBS at population-scale.

Offering complex genomic screening in acute pediatric settings: Family decision-making and outcomes

PURPOSE

Families of children in pediatric acute care who are offered ultrarapid genomic sequencing are making complex decisions during a high-stress period. To reduce complexity for families and clinicians, we offered genomic screening for the child and parents after the completion of diagnostic testing. We evaluated uptake, understanding, and service delivery preferences.

METHODS

A cohort of 235 families who had completed ultrarapid diagnostic genomic sequencing at 17 Australian hospitals were offered up to 3 screens on their genomic data: pediatric-onset, adult-onset, and expanded couple carrier screening. We investigated decision making, understanding, and service delivery preferences using surveys at 3 time points (pre counseling, post counseling, and post result) and performed inductive content analysis of pretest genetic counseling transcripts.

RESULTS

A total of 119 families (51%) attended genetic counseling with 115 (49%) accepting genomic screening. Survey respondents were more likely to find decisions about couple carrier screening easy (87%) compared with adult (68%; P = .002) or pediatric (71%; P = .01) screening decisions. All respondents with newly detected pathogenic variants accurately recalled this 1 month later. A delayed offer of screening was acceptable to most respondents (78%).

CONCLUSION

Separating genomic screening from the stressful diagnostic period is supported by families who demonstrate good knowledge and recall. Our results suggest delaying genomic screening should be trialed more widely.

Expanded Newborn Screening Using Genome Sequencing for Early Actionable Conditions

Importance

The feasibility of implementing genome sequencing as an adjunct to traditional newborn screening (NBS) in newborns of different racial and ethnic groups is not well understood.

Objective

To report interim results of acceptability, feasibility, and outcomes of an ongoing genomic NBS study in a diverse population in New York City within the context of the New York State Department of Health Newborn Screening Program.

Design, Setting, and Participants

The Genomic Uniform-screening Against Rare Disease in All Newborns (GUARDIAN) study was a multisite, single-group, prospective, observational investigation of supplemental newborn genome screening with a planned enrollment of 100 000 participants. Parent-reported race and ethnicity were recorded at the time of recruitment. Results of the first 4000 newborns enrolled in 6 New York City hospitals between September 2022 and July 2023 are reported here as part of a prespecified interim analysis.

Exposure

Sequencing of 156 early-onset genetic conditions with established interventions selected by the investigators were screened in all participants and 99 neurodevelopmental disorders associated with seizures were optional.

Main Outcomes and Measures

The primary outcome was screen-positive rate. Additional outcomes included enrollment rate and successful completion of sequencing.

Results

Over 11 months, 5555 families were approached and 4000 (72.0%) consented to participate. Enrolled participants reflected a diverse group by parent-reported race (American Indian or Alaska Native, 0.5%; Asian, 16.5%; Black, 25.1%; Native Hawaiian or Other Pacific Islander, 0.1%; White, 44.7%; 2 or more races, 13.0%) and ethnicity (Hispanic, 44.0%; not Hispanic, 56.0%). The majority of families consented to screening of both groups of conditions (both groups, 90.6%; disorders with established interventions only, 9.4%). Testing was successfully completed for 99.6% of cases. The screen-positive rate was 3.7%, including treatable conditions that are not currently included in NBS.

Conclusions and Relevance

These interim findings demonstrate the feasibility of targeted interpretation of a predefined set of genes from genome sequencing in a population of different racial and ethnic groups. DNA sequencing offers an additional method to improve screening for conditions already included in NBS and to add those that cannot be readily screened because there is no biomarker currently detectable in dried blood spots. Additional studies are required to understand if these findings are generalizable to populations of different racial and ethnic groups and whether introduction of sequencing leads to changes in management and improved health outcomes.

Trial Registration

ClinicalTrials.gov Identifier: NCT05990179.

WES-based screening of 7,000 newborns: A pilot study in Russia

The effective implementation of whole-exome sequencing- and whole-genome sequencing-based diagnostics in the management of children affected with genetic diseases and the rapid decrease in the cost of next-generation sequencing (NGS) enables the expansion of this method to newborn genetic screening programs. Such NGS-based screening greatly increases the number of diseases that can be detected compared to conventional newborn screening, as the latter is aimed at early detection of a limited number of inborn diseases. Moreover, genetic testing provides new possibilities for family members of the proband, as many variants responsible for adult-onset conditions are inherited from the parents. However, the idea of NGS-based screening in healthy children raises issues of medical and ethical integrity as well as technical questions, including interpretation of the observed variants. Pilot studies have shown that both parents and medical professionals have moved forward and are enthused about these new possibilities. However, either the number of participants or the number of genes studied in previous investigations thus far has been limited to a few hundred, restricting the scope of potential findings. Our current study (NCT05325749) includes 7,000 apparently healthy infants born at our center between February 2021 and May 2023, who were screened for pathogenic variants in 2,350 genes. Clinically significant variants associated with early-onset diseases that can be treated, prevented, or where symptoms can be alleviated with timely introduced symptomatic therapy, were observed in 0.9% of phenotypically normal infants, 2.1% of the screened newborns were found to carry variants associated with reduced penetrance or monogenic diseases of adult-onset and/or variable expressivity, and 0.3% had chromosomal abnormalities. Here, we report our results and address questions regarding the interpretation of variants in newborns who were presumed to be healthy.

Perceptions of genomic newborn screening: a cross-sectional survey conducted with UK medical students

BACKGROUND

With the potential to identify a vast number of rare diseases soon after birth, genomic newborn screening (gNBS) could facilitate earlier interventions and improve health outcomes. Designing a gNBS programme will involve balancing stakeholders' opinions and addressing concerns. The views of medical students-future clinicians who would deliver gNBS-have not yet been explored.

METHODS

We conducted a nationwide online survey of UK medical students via the REDCap platform. Perceptions of gNBS, including scope of testing and potential benefits and drawbacks, were explored using a mix of multiple-choice questions, Likert scales, visual analogue scales and free-text questions.

RESULTS

In total, 116 medical students across 16 universities participated. Overall, 45% supported gNBS, with a positively skewed mean support score of 3.24 (SD 1.26, range: 1.0-5.0), and 55% felt it relevant to their future practice. Almost all agreed that infant-onset and childhood-onset diseases and conditions with effective treatments should be included. Most felt that earlier interventions and personalised care would be the most important benefit of gNBS. Other perceived benefits included earlier diagnoses, diagnosing more patients and enabling research for new treatments. However, several perceived challenges were highlighted: risk of genomic discrimination, incidental or uncertain findings, data security and breaching children's future autonomy. Students expressed conflicting opinions on the psychological impact on families, but most were concerned about a lack of support due to current resource limitations in health services. Students frequently reported having insufficient knowledge to form an opinion, which may reflect gaps in genomics education at medical school and the current lack of evidence base for gNBS.

CONCLUSION

Although some support for gNBS was demonstrated, ethicolegal and social challenges were raised, emphasising a need for ongoing discussions about the implications of gNBS.

Clues for Early Diagnosis of MEN2B Syndrome Before Medullary Thyroid Carcinoma

Early onset medullary thyroid carcinoma, later pheochromocytomas, and nonspecific extra-endocrine features (hypermobility and persistent constipation) are part of the clinical phenotype of Multiple Endocrine Neoplasia type 2B (MEN2B). A de novo pathogenic M918T variant in the rearranged during transfection proto-oncogene is usually identified. Affected children are often seen by multiple clinicians over a long period before consideration of a diagnosis of MEN2B, with metastatic medullary thyroid carcinoma often the precipitator. We describe the clinical presentation and course of 5 children ultimately diagnosed with MEN2B in New South Wales and the Australian Capital Territory, Australia between 1989 and 2021. All cases had intestinal ganglioneuromatosis that could have prompted an earlier diagnosis. Population wide newborn genomic screening for rare diseases is on the horizon. We propose that MEN2B genomic screening should be included in newborn screening programs and that careful exclusion of intestinal ganglioneuromatosis would allow earlier identification leading to improved clinical outcomes.

Contiguous Gene Syndromes and Hearing Loss: A Clinical Report of Xq21 Deletion and Comprehensive Literature Review

Given the crucial role of the personalized management and treatment of hearing loss (HL), etiological investigations are performed early on, and genetic analysis significantly contributes to the determination of most syndromic and nonsyndromic HL cases. Knowing hundreds of syndromic associations with HL, little comprehensive data about HL in genomic disorders due to microdeletion or microduplications of contiguous genes is available. Together with the description of a new patient with a novel 3.7 Mb deletion of the Xq21 critical locus, we propose an unreported literature review about clinical findings in patients and their family members with Xq21 deletion syndrome. We finally propose a comprehensive review of HL in contiguous gene syndromes in order to confirm the role of cytogenomic microarray analysis to investigate the etiology of unexplained HL.

Gene selection for genomic newborn screening: Moving toward consensus?

PURPOSE

Gene selection for genomic newborn screening (gNBS) underpins the validity, acceptability, and ethical application of this technology. Existing gNBS gene lists are highly variable despite being based on shared principles of gene-disease validity, treatability, and age of onset. This study aimed to curate a gNBS gene list that builds upon existing efforts and provide a core consensus list of gene-disease pairs assessed by multiple expert groups worldwide.

METHODS

Our multidisciplinary expert team curated a gene list using an open platform and multiple existing curated resources. We included severe treatable disorders with age of disease onset <5 years with established gene-disease associations and reliable variant detection. We compared the final list with published lists from 5 other gNBS projects to determine consensus genes and to identify areas of discrepancy.

RESULTS

We reviewed 1279 genes and 604 met our inclusion criteria. Metabolic conditions comprised the largest group (25%), followed by immunodeficiencies (21%) and endocrine disorders (15%). We identified 55 consensus genes included by all 6 gNBS research projects. Common reasons for discrepancy included variable definitions of treatability and strength of gene-disease association.

CONCLUSION

We have identified a consensus gene list for gNBS that can be used as a basis for systematic harmonization efforts internationally.

Perception of genomic newborn screening among peripartum mothers

Advances in genomic technology have generated possibilities for expanding newborn screening from traditional procedures to genomic newborn screening (gNBS). However, before the implementation of gNBS, it is crucial to address various aspects, including parental attitudes, at the national level. With this aim, we analyzed the attitudes and expectations of Slovenian peripartum mothers regarding gNBS and the acceptability of its implementation into the Slovenian health system. A questionnaire-based study was conducted on a convenience sample of 1136 peripartum mothers (a response rate of 84.1%) in a hospital setting in Slovenia. We measured participants' level of general genetic knowledge, motivation to undergo gNBS, attitude toward its benefits and drawbacks, willingness to participate financially, and factors that would influence their decision to undergo gNBS. Most participants exhibited a positive attitude (83.2%) and were motivated to undertake gNBS (63.4%). They were willing to share genetic data and also contribute to the testing costs. Mothers with better genetic literacy and higher education level, and those with the familial genetic testing experiences were more supportive of gNBS. However, several emotional and socio-ethical concerns were raised regarding how the genetic information would influence family and social life.

Australian Public Perspectives on Genomic Newborn Screening: Risks, Benefits, and Preferences for Implementation

Recent dramatic reductions in the timeframe in which genomic sequencing can deliver results means its application in time-sensitive screening programs such as newborn screening (NBS) is becoming a reality. As genomic NBS (gNBS) programs are developed around the world, there is an increasing need to address the ethical and social issues that such initiatives raise. This study therefore aimed to explore the Australian public's perspectives and values regarding key gNBS characteristics and preferences for service delivery. We recruited English-speaking members of the Australian public over 18 years of age via social media; 75 people aged 23-72 participated in 1 of 15 focus groups. Participants were generally supportive of introducing genomic sequencing into newborn screening, with several stating that the adoption of such revolutionary and beneficial technology was a moral obligation. Participants consistently highlighted receiving an early diagnosis as the leading benefit, which was frequently linked to the potential for early treatment and intervention, or access to other forms of assistance, such as peer support. Informing parents about the test during pregnancy was considered important. This study provides insights into the Australian public's views and preferences to inform the delivery of a gNBS program in the Australian context.

Prenatal and postnatal genetic testing toward personalized care: The non-invasive perinatal testing

This article investigates how non-invasive prenatal testing and the incorporation of genomic sequencing into newborn screening postnatally are transforming perinatal care. They improve the accuracy of prenatal and neonatal screening, allowing for early interventions and personalized therapies. Non-invasive prenatal testing before birth and saliva-sample-based newborn genomic sequencing after birth can be collectively referred to as non-invasive perinatal testing. Non-invasive prenatal testing is particularly useful for aneuploidy, whereas performance markers worsen as DNA abnormalities shrink in size. Screening for clinically actionable diseases in childhood would be crucial to personalized medical therapy, as the postnatal period remains appropriate for screening for the great majority of monogenic disorders. While genomic data can help diagnose uncommon diseases, challenges like ethics and equity necessitate joint approaches for appropriate integration in this revolutionary journey toward personalized care.

Genomic newborn screening for rare diseases

Rare diseases are a leading cause of infant mortality and lifelong disability. To improve outcomes, timely diagnosis and effective treatments are needed. Genomic sequencing has transformed the traditional diagnostic process, providing rapid, accurate and cost-effective genetic diagnoses to many. Incorporating genomic sequencing into newborn screening programmes at the population scale holds the promise of substantially expanding the early detection of treatable rare diseases, with stored genomic data potentially benefitting health over a lifetime and supporting further research. As several large-scale newborn genomic screening projects launch internationally, we review the challenges and opportunities presented, particularly the need to generate evidence of benefit and to address the ethical, legal and psychosocial issues that genomic newborn screening raises.

Parental Preferences for Expanded Newborn Screening: What Are the Limits?

The use of next-generation sequencing technologies such as genomic sequencing in newborn screening (NBS) could enable the detection of a broader range of conditions. We explored parental preferences and attitudes towards screening for conditions for which varying types of treatment exist with a cross-sectional survey completed by 100 parents of newborns who received NBS in Ontario, Canada. The survey included four vignettes illustrative of hypothetical screening targets, followed by questions assessing parental attitudes. Chi-square tests were used to compare frequency distributions of preferences. Results show that most parents supported NBS for conditions for which only supportive interventions are available, but to a significantly lesser degree than those with disease-specific treatments (99% vs. 82-87%, p ≤ 0.01). For conditions without an effective treatment, the type of supportive care and age of onset of the condition did not significantly alter parent perceptions of risks and benefits. Parents are interested in expanded NBS for conditions with only supportive interventions in childhood, despite lower levels of perceived benefit for the child and greater anticipated anxiety from screen-positive results. These preferences suggest that the expansion of NBS may require ongoing deliberation of perceived benefits and risks and enhanced approaches to education, consent, and support.

Are We Ready for Whole Population Genomic Sequencing of Asymptomatic Newborns?

The introduction of genomic sequencing technologies into routine newborn screening programs in some form is not only inevitable but also already occurring in some settings. The question is therefore not "if" but "when and how" genomic newborn screening (GNBS) should be implemented. In April 2022, the Centre for Ethics of Paediatric Genomics held a one-day symposium exploring ethical issues relating to the use of genomic sequencing in a range of clinical settings. This review article synthesises the panel discussion and presents both the potential benefits of wide-scale implementation of genomic newborn screening, as well as its practical and ethical issues, including obtaining appropriate consent, and health system implications. A more in-depth understanding of the barriers associated with implementing genomic newborn screening is critical to the success of GNBS programs, both from a practical perspective and also in order to maintain public trust in an important public health initiative.

Australian parental perceptions of genomic newborn screening for non-communicable diseases

Background: Newborn bloodspot screening (NBS) programs have improved neonatal healthcare since the 1960s. Genomic sequencing now offers potential to generate polygenic risk score (PRS) that could be incorporated into NBS programs, shifting the focus from treatment to prevention of future noncommunicable disease (NCD). However, Australian parents' knowledge and attitudes regarding PRS for NBS is currently unknown. Methods: Parents with at least one Australian-born child under 18 years were invited via social media platforms to complete an online questionnaire aimed at examining parents' knowledge of NCDs, PRS, and precision medicine, their opinions on receiving PRS for their child, and considerations of early-intervention strategies to prevent the onset of disease. Results: Of 126 participants, 90.5% had heard the term "non-communicable disease or chronic condition," but only 31.8% and 34.4% were aware of the terms "polygenic risk score" and "precision medicine" respectively. A large proportion of participants said they would consider screening their newborn to receive a PRS for allergies (77.9%), asthma (81.0%), cancer (64.8%), cardiovascular disease (65.7%), mental illness (56.7%), obesity (49.5%), and type 2 diabetes (66.7%). Additionally, participants would primarily consider diet and exercise as interventions for specific NCDs. Discussion: The results from this study will inform future policy for genomic NBS, including expected rate of uptake and interventions that parents would consider employing to prevent the onset of disease.

Two-step offer and return of multiple types of additional genomic findings to families after ultrarapid trio genomic testing in the acute care setting: a study protocol

INTRODUCTION

As routine genomic testing expands, so too does the opportunity to look for additional health information unrelated to the original reason for testing, termed additional findings (AF). Analysis for many different types of AF may be available, particularly to families undergoing trio genomic testing. The optimal model for service delivery remains to be determined, especially when the original test occurs in the acute care setting.

METHODS AND ANALYSIS

Families enrolled in a national study providing ultrarapid genomic testing to critically ill children will be offered analysis for three types of AF on their stored genomic data: paediatric-onset conditions in the child, adult-onset conditions in each parent and reproductive carrier screening for the parents as a couple. The offer will be made 3-6 months after diagnostic testing. Parents will have access to a modified version of the Genetics Adviser web-based decision support tool before attending a genetic counselling appointment to discuss consent for AF. Parental experiences will be evaluated using qualitative and quantitative methods on data collected through surveys, appointment recordings and interviews at multiple time points. Evaluation will focus on parental preferences, uptake, decision support use and understanding of AF. Genetic health professionals' perspectives on acceptability and feasibility of AF will also be captured through surveys and interviews.

ETHICS AND DISSEMINATION

This project received ethics approval from the Melbourne Health Human Research Ethics Committee as part of the Australian Genomics Health Alliance protocol: HREC/16/MH/251. Findings will be disseminated through peer-review journal articles and at conferences nationally and internationally.

Expanding the Australian Newborn Blood Spot Screening Program using genomic sequencing: do we want it and are we ready?

Since the introduction of genome sequencing in medicine, the factors involved in deciding how to integrate this technology into population screening programs such as Newborn Screening (NBS) have been widely debated. In Australia, participation in NBS is not mandatory, but over 99.9% of parents elect to uptake this screening. Gauging stakeholder attitudes towards potential changes to NBS is vital in maintaining this high participation rate. The current study aimed to determine the knowledge and attitudes of Australian parents and health professionals to the incorporation of genomic sequencing into NBS programs. Participants were surveyed online in 2016 using surveys adapted from previous studies. The majority of parents (90%) self-reported some knowledge of NBS, with 77% expressing an interest in NBS using the new technology. This was significantly lower than those who would utilise NBS using current technologies (99%). Although, many health professionals (62%) felt that new technologies should currently not be used as an adjunct to NBS, 79% foresaw the use of genomic sequencing in NBS by 2026. However, for genomic sequencing to be considered, practical and technical challenges as well as parent information needs were identified including the need for accurate interpretation of data; pre-and post-test counselling; and appropriate parental consent and opt-out process. Therefore, although some support for implementing genomic sequencing into Australian NBS does exist, there is a need for further investigation into the ethical, social, legal and practical implications of introducing this new technology as a replacement to current NBS methods.

Offering and Returning Secondary Findings in the Context of Exome Sequencing for Hearing Loss: Clinicians' Views and Experiences

BACKGROUND

There is ongoing debate regarding whether and under which circumstances secondary findings (SF) should be offered in the pediatric context. Although studies have examined patient perspectives on receiving SF, little research has been conducted examining the experiences of clinicians offering SF to parents of newborns receiving genomic sequencing for a recently diagnosed medical condition.

METHODS

To address this, we conducted qualitative interviews exploring the views and experiences of 12 clinicians who offered SF to parents of infants who had diagnostic exome sequencing (ES) to identify the cause of their hearing loss. Interviews explored clinicians' accounts of parents' choices and decision-making about receiving SF, their views on whether and when to offer SF, their experiences returning SF, and any ethical challenges they encountered. Interviews were audio-recorded, transcribed and analyzed using inductive content analysis.

RESULTS

Clinicians reported parents who declined all SF often felt finding out about future conditions unrelated to their child's hearing loss may be unhelpful, or even harmful, or were overwhelmed by their child's diagnosis. Clinicians also reported that some parents chose SF because they felt obliged to, even if they did not want to receive them. They explained that while some parents experienced decision-making regarding SF as positive, for others, this process was challenging or distressing. While clinicians generally agreed SF should be offered, mainly to promote parental choice, most felt SF should be offered after disclosing diagnostic results, primarily to avoid overwhelming parents. Clinicians encountered several ethical challenges, including balancing parental autonomy with non-maleficence, wanting to report or not report certain SF, and questioning whether parents can make an autonomous choice regarding SF.

CONCLUSIONS

Our findings, which are novel as they relate to parents of young infants with a recent diagnosis of hearing loss, add new insights into clinicians' and parents' decision-making regarding SF in pediatrics.

Non-Syndromic Hearing Loss in a Romanian Population: Carrier Status and Frequent Variants in the GJB2 Gene

The genetic causes of autosomal recessive nonsyndromic hearing loss (ARNSHL) are heterogeneous and highly ethnic-specific. We describe GJB2 (connexin 26) variants and carrier frequencies as part of our study and summarize previously reported ones for the Romanian population. In total, 284 unrelated children with bilateral congenital NSHL were enrolled between 2009 and 2018 in northwestern Romania. A tiered diagnostic approach was used: all subjects were tested for c.35delG, c.71G>A and deletions in GJB6 (connexin 30) using PCR-based methods. Furthermore, 124 cases undiagnosed at this stage were analyzed by multiplex-ligation-dependent probe amplifications (MLPA), probe mix P163, and sequencing of GJB2 exon 2. Targeted allele-specific PCR/restriction fragment length polymorphism (RFLP) established definite ethio-pathogenical diagnosis for 72/284 (25.35%) of the cohort. Out of the 124 further analyzed, in 12 cases (9.67%), we found compound heterozygous point mutations in GJB2. We identified one case of deletion of exon 1 of the WFS1 (wolframin) gene. Carrier status evaluation used Illumina Infinium Global Screening Array (GSA) genotyping: the HINT cohort-416 individuals in northwest Romania, and the FUSE cohort-472 individuals in southwest Romania. GSA variants yielded a cumulated risk allele presence of 0.0284. A tiered diagnostic approach may be efficient in diagnosing ARNSHL. The summarized contributions to Romanian descriptive epidemiology of ARNSHL shows that pathogenic variants in the GJB2 gene are frequent among NSHL cases and have high carrier rates, especially for c.35delG and c.71G>A. These findings may serve in health strategy development.

Precision medicine via the integration of phenotype-genotype information in neonatal genome project

The explosion of next-generation sequencing (NGS) has enabled the widespread use of genomic data in precision medicine. Currently, several neonatal genome projects have emerged to explore the advantages of NGS to diagnose or screen for rare genetic disorders. These projects have made remarkable achievements, but still the genome data could be further explored with the assistance of phenotype collection. In contrast, longitudinal birth cohorts are great examples to record and apply phenotypic information in clinical studies starting at the neonatal period, especially the trajectory analyses for health development or disease progression. It is obvious that efficient integration of genotype and phenotype benefits not only the clinical management of rare genetic disorders but also the risk assessment of complex diseases. Here, we first summarize the recent neonatal genome projects as well as some longitudinal birth cohorts. Then, we propose two simplified strategies by integrating genotypic and phenotypic information in precision medicine based on current studies. Finally, research collaborations, sociological issues, and future perspectives are discussed. How to maximize neonatal genomic information to benefit the pediatric population remains an area in need of more research and effort.

The Genomics of Auditory Function and Disease

Current estimates suggest that nearly half a billion people worldwide are affected by hearing loss. Because of the major psychological, social, economic, and health ramifications, considerable efforts have been invested in identifying the genes and molecular pathways involved in hearing loss, whether genetic or environmental, to promote prevention, improve rehabilitation, and develop therapeutics. Genomic sequencing technologies have led to the discovery of genes associated with hearing loss. Studies of the transcriptome and epigenome of the inner ear have characterized key regulators and pathways involved in the development of the inner ear and have paved the way for their use in regenerative medicine. In parallel, the immense preclinical success of using viral vectors for gene delivery in animal models of hearing loss has motivated the industry to work on translating such approaches into the clinic. Here, we review the recent advances in the genomics of auditory function and dysfunction, from patient diagnostics to epigenetics and gene therapy.

A framework for reporting secondary and incidental findings in prenatal sequencing: When and for whom?

As the use of genomic sequencing (GS) in the prenatal setting becomes more widespread, laboratories and clinicians will be tasked with making decisions about whether to offer incidental and secondary findings to expectant parents and, if so, which ones. Unfortunately, few guidelines or position statements issued by professional bodies address the return of secondary findings specifically in the context of prenatal GS, nor do they offer clear guidance on whether, and which types of incidental findings should be reported. Laboratories and clinicians will also need to navigate other challenges, such as how to obtain sufficiently informed consent, workload burdens for both laboratories and clinicians, and funding. Here we discuss these, and other challenges associated with offering incidental and secondary findings in the context of prenatal GS. We outline existing guidelines for return of these findings, prenatally and in children. We review the existing literature on stakeholder perspectives on return of incidental and secondary findings and discuss the main practical and ethical challenges that require consideration. We then propose a framework to help guide decision-making, suggesting a baseline routine analysis, with additional layers of analysis that could be offered, according to local laboratory policy, with additional opt-in consent from the parents.

Clinicians' Views and Experiences with Offering and Returning Results from Exome Sequencing to Parents of Infants with Hearing Loss

Exome sequencing (ES) is an effective method for identifying the genetic cause of hearing loss in infants diagnosed through newborn hearing screening programs. ES has the potential to be integrated into routine clinical care, yet little is known about the experiences of clinicians offering this test to families. To address this gap, clinicians involved in a clinical study using ES to identify the cause of infants' hearing loss were interviewed to explore their experiences with offering and returning results to parents. Interview transcripts were analysed using inductive content analysis. Twelve clinicians participated: seven genetic counsellors, four clinical geneticists, and one paediatrician. Most clinicians were supportive of offering ES to infants with hearing loss, primarily because results may inform the child's clinical management. However, some expressed concerns, questioning the utility of this information, particularly for isolated hearing loss. Clinicians had differing views regarding the optimal time to offer ES to families; while some felt that families can manage everything at once, others recommended delaying testing until parents have come to terms with their child's diagnosis. These findings show the complexity involved in determining how ES should be offered to families following the diagnosis of a child with hearing loss, particularly with regards to when testing is suggested.

Genetics of Childhood Hearing Loss

Compelling evidence indicates that some newborns harboring genetic variants associated with hearing loss might not be identified by current physiologic newborn hearing screening (NBHS) rendering current NBHS protocols suboptimal. Incorporating genomic sequencing into NBHS would improve clinical diagnosis and decrease time to early intervention efforts.

Principles of Genomic Newborn Screening Programs: A Systematic Review

IMPORTANCE

Genomic newborn screening (gNBS) may optimize the health and well-being of children and families. Screening programs are required to be evidence based, acceptable, and beneficial.

OBJECTIVES

To identify what has been discovered following the reporting of the first gNBS pilot projects and to provide a summary of key points for the design of gNBS.

EVIDENCE REVIEW

A systematic literature review was performed on April 14, 2021, identifying 36 articles that addressed the following questions: (1) what is the interest in and what would be the uptake of gNBS? (2) what diseases and genes should be included? (3) what is the validity and utility of gNBS? and (4) what are the ethical, legal, and social implications? Articles were only included if they generated new evidence; all opinion pieces were excluded.

FINDINGS

In the 36 articles included, there was high concordance, except for gene disease inclusion, which was highly variable. Key findings were the need for equitable access, appropriate educational materials, and informed and flexible consent. The process for selecting genes for testing should be transparent and reflect that parents value the certainty of prediction over actionability. Data should be analyzed in a way that minimizes uncertainty and incidental findings. The expansion of traditional newborn screening (tNBS) to identify more life-threatening and treatable diseases needs to be balanced against the complexity of consenting parents of newborns for genomic testing as well as the risk that overall uptake of tNBS may decline. The literature reflected that the right of a child to self-determination should be valued more than the possibility of the whole family benefiting from a newborn genomic test.

CONCLUSIONS AND RELEVANCE

The findings of this systematic review suggest that implementing gNBS will require a nuanced approach. There are gaps in our knowledge, such as the views of diverse populations, the capabilities of health systems, and health economic implications. It will be essential to rigorously evaluate outcomes and ensure programs can evolve to maximize benefit.

Personal utility of genomic sequencing for infants with congenital deafness

Decisions about genetic testing have traditionally been based on clinical utility and cost, but personal utility is increasingly recognized when assessing the value of testing. Whole exome sequencing (WES) was offered to a population cohort of 106 infants diagnosed with congenital hearing loss. Parents could choose to receive results relating to hearing loss only or also learn additional information about childhood-onset conditions (medically nonactionable and/or actionable). This study aimed to quantify the personal utility of WES for parents after a diagnosis of hearing loss in their child. Parents completed surveys pretest (63/106), after hearing loss results (52/106) and after receiving additional information (47/72). Open-ended responses from all three surveys (N = 67) were analyzed using inductive content analysis. Answers to questions regarding the value of sequencing to parents were analyzed and collated. Parents placed high value on diagnostic WES for hearing loss but had different perspectives on the personal utility of additional information. Diagnostic results provided certainty while the choice to learn additional information about childhood-onset disorders was associated with empowerment. WES also represented an opportunity to promote their child's best interests. Results provide insights into the utility of WES for the indication of congenital deafness and for genomic newborn screening broadly.

A decision aid for additional findings in genomic sequencing: Development and pilot testing

OBJECTIVE

To describe the development of a web-based, patient-facing decision aid to support patients and research participants to make an informed, values-based decision about whether to receive additional results from genomic sequencing.

METHODS

We developed the decision aid following the multi-step process described in the International Patient Decision Aids Standards. This utilized literature review, focus groups, and alpha testing with research participants undergoing clinical genomic sequencing.

RESULTS

The decision aid, the Optional Results Choice Aid (ORCA), includes a seven-question "values clarification exercise," illustrative patient quotes, and summative guidance for the user. The decision aid was found to be highly readable, acceptable and relevant in alpha testing.

CONCLUSION

We developed a decision aid to support informed, values-based decision making for patients and research participants considering whether to receive additional results from genomic sequencing. ORCA is being implemented in the NHGRI-funded Cancer Health Assessment Reaching Many (CHARM) study, where we are measuring informed values-choice congruence.

PRACTICE IMPLICATIONS

ORCA was designed to support patients and research participants to make an informed, values-based decision about whether to receive additional results from genomic sequencing.

Exome Sequencing for Isolated Congenital Hearing Loss: A Cost-Effectiveness Analysis

OBJECTIVES/HYPOTHESIS

To assess the relative cost-effectiveness of exome sequencing for isolated congenital deafness compared with standard care.

STUDY DESIGN

Incremental cost-effectiveness and cost-benefit analyses were undertaken from the perspective of the Australian healthcare system using an 18-year time horizon.

METHODS

A decision tree was used to model the costs and outcomes associated with exome sequencing and standard care for infants presenting with isolated congenital deafness.

RESULTS

Exome sequencing resulted in an incremental cost of AU$1,000 per child and an additional 30 diagnoses per 100 children tested. The incremental cost-effectiveness ratio was AU$3,333 per additional diagnosis. The mean societal willingness to pay for exome sequencing was estimated at AU$4,600 per child tested relative to standard care, resulting in a positive net benefit of AU$3,600. Deterministic and probabilistic sensitivity analyses confirmed the cost-effectiveness of exome sequencing.

CONCLUSIONS

Our findings demonstrate the cost-effectiveness of exome sequencing in congenital hearing loss, through increased diagnostic rate and consequent improved process of care by reducing or ceasing diagnostic investigation or facilitating targeted further investigation. We recommend equitable funding for exome sequencing in infants presenting with isolated congenital hearing loss.

LEVEL OF EVIDENCE

N/A. Laryngoscope, 131:E2371-E2377, 2021.