Can incorporating molecular testing improve the accuracy of newborn screening for congenital adrenal hyperplasia?

BACKGROUND: Single-tier newborn screening (NBS) for CAH using 17-hydroxyprogesterone (17OHP) measured by fluoroimmunoassay (FIA) in samples collected at 24-48 hours produces a high false-positive rate (FPR). 2nd tier steroid testing can reduce the FPR and has been widely implemented. We investigated the accuracy of an alternative multi-tier CAH NBS protocol that incorporates molecular testing of the CYP21A2 gene and reduces the 1st tier 17OHP cutoff to minimize missed cases. METHODS: Created a Minnesota-specific CYP21A2 pathogenic variants panel; develop a rapid, high-throughput multiplex, allele-specific-primer-extension assay; perform 1-year retrospective analysis of Minnesota NBS results comparing metrics between a conventional steroid-based two-tier protocol and a molecular-based multi-tier NBS protocol, applied post-hoc. RESULTS: CYP21A2 gene sequencing of 103 Minnesota families resulted in a Minnesota-specific panel of 21 pathogenic variants. Centers for Disease Control and Prevention (CDC) created a molecular assay with 100% accuracy and reproducibility. Two-tier steroid-based screening of 68,659 live births during 2015 resulted in 2 false negatives (FNs), 91 FPs, and 1 true positive (TP). A three-tier protocol with a lower 1st-tier steroid cutoff, 2nd-tier 21-variant CYP21A2 panel and 3rd-tier CYP21A2 sequencing would have resulted in 0 FNs, 52 FPs and 3 TPs. CONCLUSIONS: Incorporation of molecular testing could improve the accuracy of CAH NBS, although some distinct challenges of molecular testing may need to be considered before implementation by NBS programs.

Consensus guidelines for the monitoring and management of metachromatic leukodystrophy in the United States.

Metachromatic leukodystrophy (MLD) is a fatal, progressive neurodegenerative disorder caused by biallelic pathogenic mutations in the ARSA (Arylsulfatase A) gene. With the advent of presymptomatic diagnosis and the availability of therapies with a narrow window for intervention, it is critical to define a standardized approach to diagnosis, presymptomatic monitoring, and clinical care. To meet the needs of the MLD community, a panel of MLD experts was established to develop disease-specific guidelines based on healthcare resources in the United States. This group developed a consensus opinion for best-practice recommendations, as follows: (i) Diagnosis should include both genetic and biochemical testing; (ii) Early diagnosis and treatment for MLD is associated with improved clinical outcomes; (iii) The panel supported the development of newborn screening to accelerate the time to diagnosis and treatment; (iv) Clinical management of MLD should include specialists familiar with the disease who are able to follow patients longitudinally; (v) In early onset MLD, including late infantile and early juvenile subtypes, ex vivo gene therapy should be considered for presymptomatic patients where available; (vi) In late-onset MLD, including late juvenile and adult subtypes, hematopoietic cell transplant (HCT) should be considered for patients with no or minimal disease involvement. This document summarizes current guidance on the presymptomatic monitoring of children affected by MLD as well as the clinical management of symptomatic patients. Future data-driven evidence and evolution of these recommendations will be important to stratify clinical treatment options and improve clinical care.

Newborn Screening for Severe Combined Immunodeficiency: Lessons Learned from Screening and Follow-Up of the Preterm Newborn Population.

Newborn screening (NBS) for Severe Combined Immunodeficiency (SCID) by measurement of T-cell receptor excision circles (TRECs) successfully identifies newborns with SCID and severe T-cell lymphopenia, as intended. At the same time, NBS programs face the challenge of false positive results, with a disproportionately high number in the premature newborn population. This study evaluates TREC values and SCID screening outcomes in premature newborns and elucidates evidence-based SCID screening practices that reduce unnecessary follow-up activities in this population. De-identified individual SCID newborn screening data and aggregate SCID screening data were obtained from seven states across the US for babies born between 2018 and 2020. Relevant statistics were performed on data pooled from these states to quantify screening performance metrics and clinical impact on various birth and gestational age categories of newborns. The data were normalized using multiples-of-the-median (MoM) values to allow for the aggregation of data across states. The aggregation of NBS data across a range of NBS programs highlighted the trajectory of TREC values over time, both between and within newborns, and provides evidence for improved SCID screening recommendations in the premature and low birth weight population.

Infants with Congenital Diseases Identified through Newborn Screening-United States, 2018-2020.

Newborn screening (NBS) is a state or territory-based public health system that screens newborns for congenital diseases that typically do not present with clinical symptoms at birth but can cause significant mortality and morbidity if not detected or treated quickly. NBS continues to be one of the most successful public health interventions in the US, providing early detection and intervention to all infants. The increase in overall birth prevalence of core Recommended Uniform Screening Panel (RUSP) diseases detected via dried blood spot (DBS) specimens from 2015-2017 (17.50-18.31 per 10,000) to 2018-2020 (20.07 per 10,000), as reported into the APHL NewSTEPs database, affirms the importance and impact of NBS programs. This report presents aggregate numbers and birth prevalence of diseases detected by DBS on the RUSP from 2018-2020, including data from fifty US states and two territories.

Gene-targeted therapies: Towards equitable development, diagnosis, and access.

Genomic and gene-targeted therapies hold great promise in addressing the global issue of rare diseases. To achieve this promise, however, it is critical the twin goals of equity in access to testing and diagnosis, and equity in access to therapy be considered early in the life cycle of development and implementation. Rare disease researchers and clinicians must simultaneously recognize the life-altering potential of early diagnosis and administration of gene-targeted therapeutics while acknowledging that not everyone who experiences a rare disease and needs these therapies will be able to afford or access them. Achieving equity in the development of and access to gene-targeted therapies will not only require innovations in research, clinical, regulatory, and reimbursement frameworks, but will also necessitate increased attention to the ethical, legal, and social implications when establishing research paradigms and the translation of research results into novel interventions for rare genetic diseases. This article highlights and discusses the growing importance and recognition of health equity across the spectrum of rare disease research and care delivery.

Scaling genetic resources: New paradigms for diagnosis and treatment of rare genetic disease.

Development of genetic tests for rare genetic diseases has traditionally focused on individual diseases. Similarly, development of new therapies occurred one disease at a time. With >10,000 rare genetic diseases, this approach is not feasible. Diagnosis of genetic disorders has already transcended old paradigms as whole exome and genome sequencing have allowed expedient interrogation of all relevant genes in a single test. The growth of newborn screening has allowed identification of diseases in presymptomatic babies. Similarly, the ability to develop therapies is rapidly expanding due to technologies that leverage platform technology that address multiple diseases. However, movement from the basic science laboratory to clinical trials is still hampered by a regulatory system rooted in traditional trial design, requiring a fresh assessment of safe ways to obtain approval for new drugs. Ultimately, the number of nucleic acid-based therapies will challenge the ability of clinics focused on rare diseases to deliver them safely with appropriate evaluation and long-term follow-up. This manuscript summarizes discussions arising from a recent National Institutes of Health conference on nucleic acid therapy, with a focus on scaling technologies for diagnosis of rare disorders and provision of therapies across the age and disease spectrum.

Population-Based Screening of Newborns: Findings From the NBS Expansion Study (Part One).

Each year, through population-based newborn screening (NBS), 1 in 294 newborns is identified with a condition leading to early treatment and, in some cases, life-saving interventions. Rapid advancements in genomic technologies to screen, diagnose, and treat newborns promise to significantly expand the number of diseases and individuals impacted by NBS. However, expansion of NBS occurs slowly in the United States (US) and almost always occurs condition by condition and state by state with the goal of screening for all conditions on a federally recommended uniform panel. The Newborn Screening Translational Research Network (NBSTRN) conducted the NBS Expansion Study to describe current practices, identify expansion challenges, outline areas for improvement in NBS, and suggest how models could be used to evaluate changes and improvements. The NBS Expansion Study included a workshop of experts, a survey of clinicians, an analysis of data from online repositories of state NBS programs, reports and publications of completed pilots, federal committee reports, and proceedings, and the development of models to address the study findings. This manuscript (Part One) reports on the design, execution, and results of the NBS Expansion Study. The Study found that the capacity to expand NBS is variable across the US and that nationwide adoption of a new condition averages 9.5 years. Four factors that delay and/or complicate NBS expansion were identified. A companion paper (Part Two) presents a use case for each of the four factors and highlights how modeling could address these challenges to NBS expansion.

Newborn Screening for Cystic Fibrosis: A Qualitative Study of Successes and Challenges from Universal Screening in the United States.

Cystic fibrosis (CF) newborn screening (NBS) was universally adopted in 2009 in the United States. Variations in NBS practices between states may impact the timing of diagnosis and intervention. Quantitative metrics can provide insight into NBS programs (NBSP), but the nuances cannot be elucidated without additional feedback from programs. This study was designed to determine facilitators and barriers to timely diagnosis and intervention following NBS for CF. The median age at the first CF event for infants with CF within each state was used to define early and late states (n = 15 per group); multiple CF centers were invited in states with more than two CF centers. Thirty states were eligible, and 61 NBSP and CF centers were invited to participate in structured interviews to determine facilitators and barriers. Once saturation of themes was reached, no other interviews were conducted. Forty-five interviews were conducted (n = 16 early CF center, n = 12 late CF center, n = 11 early NBSP, and n = 6 late NBSP). Most interviewees reported good communication between CF centers and NBSP. Communication between primary care providers (PCPs) and families was identified as a challenge, leading to delays in referral and subsequent diagnosis. The misperception of low clinical risk in infants from racial and ethnic minority groups was a barrier to early diagnostic evaluation for all groups. NBSP and CF centers have strong relationships. Early diagnosis may be facilitated through more engagement with PCPs. Quality improvement initiatives should focus on continuing strong partnerships between CF centers and NBS programs, improving education, communication strategies, and partnerships with PCPs, and improving CF NBS timeliness and accuracy.

Newborn screening for neurodevelopmental diseases: Are we there yet?

In the US, newborn screening (NBS) is a unique health program that supports health equity and screens virtually every baby after birth, and has brought timely treatments to babies since the 1960's. With the decreasing cost of sequencing and the improving methods to interpret genetic data, there is an opportunity to add DNA sequencing as a screening method to facilitate the identification of babies with treatable conditions that cannot be identified in any other scalable way, including highly penetrant genetic neurodevelopmental disorders (NDD). However, the lack of effective dietary or drug-based treatments has made it nearly impossible to consider NDDs in the current NBS framework, yet it is anticipated that any treatment will be maximally effective if started early. Hence there is a critical need for large scale pilot studies to assess if and how NDDs can be effectively screened at birth, if parents desire that information, and what impact early diagnosis may have. Here we attempt to provide an overview of the recent advances in NDD treatments, explore the possible framework of setting up a pilot study to genetically screen for NDDs, highlight key technical, practical, and ethical considerations and challenges, and examine the policy and health system implications.

COVID-19 Pandemic-Related Impacts on Newborn Screening Public Health Surveillance.

Newborn screening (NBS) is an essential public health service that performs screening to identify those newborns at increased risk for a panel of disorders, most of which are genetic. The goal of screening is to link those newborns at the highest risk to timely intervention and potentially life-saving treatment. The global COVID-19 pandemic led to disruptions within the United States public health system, revealing implications for the continuity of newborn screening laboratories and follow-up operations. The impacts of COVID-19 across different states at various time points meant that NBS programs impacted by the pandemic later could benefit from the immediate experiences of the earlier impacted programs. This article will review the collection, analysis, and dissemination of information during the COVID-19 pandemic facilitated by a national, centralized technical assistance and resource center for NBS programs.

Common Challenges and Identified Solutions for State Newborn Screening Programs during COVID-19 Pandemic.

During the COVID-19 pandemic, state newborn screening programs faced challenges to ensure this essential public health program continued to function at a high level. In December 2020, the EveryLife Foundation for Rare Diseases held a workshop to discuss these common challenges and solutions. Newborn screening officials described challenges including short staffing across the entire program, collection and transport of specimens, interrupted follow-up activities, and pilot study recruitment. To address these challenges, state programs implemented a wide variety of solutions to maintain the high standards of newborn screening. To address staffing issues, newborn screening programs, public health laboratories, and hospitals all cross-trained personnel, worked to manage staff stress, and established essential functions. Other solutions included working with courier companies to ensure the timely pick-up of specimen, creating educational materials for hospital staff, and the creation of hybrid recruitment models for pilot studies. Implementing the lessons discussed throughout this paper can help to prepare for the next public health emergencies to ensure that a program that interacts with millions of families every year and saves the lives of thousands of children every year is minimally impacted.

Genomics and Newborn Screening: Perspectives of Public Health Programs.

This study assesses the benefits and challenges of using genomics in Newborn Screening Programs (NBS) from the perspectives of State program officials. This project aims to help programs develop policies that will aid in the integration of genomic technology. Discussion groups were conducted with the NBS Program and Laboratory Directors in the seven HRSA Regional Genomics Collaboratives (August 2014-March 2016). The discussion groups addressed expected uses of genomics, potential benefits, and challenges of integrating genomic technology, and educational needs for parents and other NBS stakeholders: Twelve focus groups were conducted, which included participants from over 40 state programs. Benefits of incorporating genomics included improving screening modalities, supporting diagnostic procedures, and screening for a wider spectrum of disorders. Challenges included the costs of genomics, the ability to educate parents and health care providers about results, and the potential negative psychosocial impact of genomic information. Attempts to address the challenges of integrating genomics must focus on preserving the child welfare goals of NBS programs. Health departments will need to explore how genomics could be used to enhance programs while maintaining universal access to screening.

Development of an Implementation Framework for Overcoming Underdiagnoses of Familial Hypercholesterolemia in the USA.

Familial hypercholesterolemia (FH) is a genetic condition which causes elevated low-density lipoprotein cholesterol from birth. With a prevalence of 1 in 250 and the availability of effective treatments, the diagnostic rate of <1 to 10% is unacceptably low. Screening for FH is supported by multiple organizations, but it has not been broadly adopted and implemented across the USA. To investigate the implementation of FH screening, key informants were recruited from across the USA for their expertise in FH-related literature, guidelines, public health, and/or advocacy to complete -semistructured interviews guided by implementation science (RE-AIM framework). Sixteen semistructured interviews were analyzed with directed content and thematic analyses, yielding specific barriers and recommendations to improve FH screening. Barriers to FH screening included patient recruitment and participation, equitable access to healthcare, provider discomfort with screening and treating FH, provider burden, lack of public health and legislative support, FH awareness, guideline complexity, facilitation of genetic testing and cascade screening, and lack of coordination between stakeholders. Awareness, engagement, communication, and collaboration between stakeholders is integral to successful FH screening. Individualized plans will be required at national, regional, and institutional levels. FH screening implementation can be achieved through practice facilitation, streamlined screening approaches, electric medical record tools, and consensus guidelines to increase screening adoption and consistent delivery. Reliable funding and established lines of communication between stakeholders can maintain efforts as FH screening progresses.

Updated Strategies for Pulse Oximetry Screening for Critical Congenital Heart Disease.

Seven years after its addition to the US Recommended Uniform Screening Panel, newborn screening for critical congenital heart disease (CCHD) using pulse oximetry became mandatory in the United States. Although CCHD newborn screening reduces morbidity and mortality, there remain important opportunities to improve. An expert panel convened for a 1-day meeting in September 2018, including subject matter experts and representatives from stakeholder organizations. Presentations on CCHD outcomes, variations in approach to screening, and data and quality improvement helped identify improvement opportunities. The expert panel concluded that sufficient evidence exists to recommend modifying the current American Academy of Pediatrics algorithm by (1) requiring an oxygen saturation of at least 95% in both (formerly either) the upper and lower extremities to pass and (2) requiring only 1 repeat screen instead of 2 for cases that neither pass nor fail initially. The panel underscored the importance of improving public health reporting by further specifying the targets of screening and criteria for reporting outcomes (false-negative and false-positive cases). The panel also highlighted the need to ensure sufficient public health funding for CCHD newborn screening and opportunities for education and global implementation. Newborn screening for CCHD using pulse oximetry has led to significant improvements in child health outcomes. However, further important work is required to understand and improve the effectiveness and efficiency of screening.

A report on state-wide implementation of newborn screening for X-linked Adrenoleukodystrophy.

Minnesota became the fourth state to begin newborn screening (NBS) for X-linked adrenoleukodystrophy (X-ALD) in 2017. As there is limited retrospective data available on NBS for X-ALD, we analyzed Minnesota's NBS results from the first year of screening. C26:0 lysophosphatidylcholine (C26:0-LPC) screening results of 67,836 infants and confirmatory testing (ABCD1 gene and serum VLCFA analysis) for screen positives were obtained. Fourteen infants (nine males, five females) screened positive for X-ALD and all were subsequently confirmed to have X-ALD, with zero false positives. The birth prevalence of X-ALD in screened infants was 1 in 4,845 and 1 in 3,878 males, more than five times previous reported incidences. Pedigrees of affected infants were analyzed, and 17 male (mean age of 17) and 24 female relatives were subsequently diagnosed with X-ALD. Phenotypes of these family members included self-reported mild neuropathy symptoms in two males and seven females, and childhood cerebral disease (ccALD) and adrenal insufficiency in one male. We observed fewer cases of ccALD and adrenal insufficiency than expected in male family members (5.9% of males for both) compared to previous observations. Together, these findings suggest that the spectrum of X-ALD may be broader than previously described and that milder cases may previously have been underrepresented. Other challenges included a high frequency of variants of uncertain significance in ABCD1 and an inability to predict phenotypic severity. We posit that thoughtful planning to address these novel challenges and coordination by dedicated specialists will be imperative for successful implementation of population-based screening for X-ALD.

Actions in Support of Newborn Screening for Critical Congenital Heart Disease - United States, 2011-2018.

In 2011, the U.S. Department of Health and Human Services added critical congenital heart disease (CCHD), which occurs in two of every 1,000 births, to the list of conditions recommended to states for universal newborn screening (1). Without early detection, infants with CCHD are at risk for substantial morbidity and death in the first weeks and months of life (2). Based on 2007-2013 data, deaths from CCHD and other cardiac causes in infants aged <6 months significantly declined in infants born in eight states after they had fully implemented mandated newborn CCHD screening policies by June 2013 (3). CDC collaborated with the American Academy of Pediatrics (AAP) and the Association of Public Health Laboratories' Newborn Screening Technical Assistance and Evaluation Program (NewSTEPs) to update a 2015 report (4) on states' actions toward adopting and implementing policies supporting CCHD newborn screening. In 2018, all 50 states and the District of Columbia (DC) had implemented CCHD screening policies, and, with one exception, all states mandated that screening be done (California mandates that screening be offered). However, not all states had data systems in place for tracking all screening results and outcomes. Ongoing evaluation activities, which rely on screening data, could help identify program improvement opportunities and monitor the impact of early identification of CCHD.

A Newborn Screening Education Best Practices Framework: Development and Adoption.

Newborn screening is a process-based public health service. Newborn screening staff and families alike are essential to maintaining the timeliness of the screening process. Newborn screening education must be accurate and accessible. Past newborn screening conferences have highlighted gaps in best practice and evidence-based guidance on newborn screening education. Sharing successful strategies across programs mitigates the scarcity of resources by cutting costs and reducing the burden of work. These factors illustrate the need for an education framework to guide newborn screening education efforts. The Newborn Screening Education Best Practices Framework responds to these issues by outlining guidance for newborn screening education approaches. Experts in the fields of newborn screening, genetics, and bioethics as well as previous research on best practice guidelines have contributed to the development of this framework. The framework outlines a process for users to evaluate newborn screening education approaches as best practices. This framework reviews best practices using a two-step approach, looking at guiding questions, implementation of the newborn screening issue, and evaluation. The framework helps the user define the characteristics of the newborn screening issue, intended audience, and practical steps to implementation, and then decide whether or not it can be used as a best practice.

Introduction to the Special Issue: Public Health Genetics and Genomics.

This special issue of the Journal of Genetic Counseling is dedicated to public health genetics and genomics. The seventeen papers featured in this issue span such topics as genetic counselors in public health roles, newborn screening, population screening, ethics, and health beliefs and behaviors. In this introduction to the special issue, we review some history of public health genetics and genomics, present the Centers for Disease Control and Prevention's "10 Essential Public Health Services" with associated genetics specific recommendations and priorities, and briefly overview how each article ties into the world of public health genetics and genomics. We hope this issue encourages genetic counselors to visualize their ever expanding and important roles in public health genetics and genomics, as well as their contributions to improving population health.