Whole-genome sequencing holds the key to the success of gene-targeted therapies.

Rare genetic disorders affect as many as 3%-5% of all babies born. Approximately 10,000 such disorders have been identified or hypothesized to exist. Treatment is supportive except in a limited number of instances where specific therapies exist. Development of new therapies has been hampered by at least two major factors: difficulty in diagnosing diseases early enough to enable treatment before irreversible damage occurs, and the high cost of developing new drugs and getting them approved by regulatory agencies. Whole-genome sequencing (WGS) techniques have become exponentially less expensive and more rapid since the beginning of the human genome project, such that return of clinical data can now be achieved in days rather than years and at a cost that is comparable to other less expansive genetic testing. Thus, it is likely that WGS will ultimately become a mainstream, first-tier NBS technique at least for those disorders without appropriate high-throughput functional tests. However, there are likely to be several steps in the evolution to this end. The clinical implications of these advances are profound but highlight the bottlenecks in drug development that still limit transition to treatments. This article summarizes discussions arising from a recent National Institute of Health conference on nucleic acid therapy, with a focus on the impact of WGS in the identification of diagnosis and treatment of rare genetic disorders.

The Progress and Future of US Newborn Screening.

Progress in newborn screening (NBS) has been driven for 60 years by developments in science and technology, growing consumer advocacy, the actions of providers involved in the care of rare disease patients, and by federal and State government funding and policies. With the current explosion of clinical trials of treatments for rare diseases, the pressure for expansion has grown, and concerns about the capacity for improvement and growth are being expressed. Genome and exome sequencing (GS/ES) have now opened more opportunities for early identification and disease prevention at all points in the lifespan. The greatest challenge facing NBS stems from the conditions most amenable to screening, and new treatment development is that we are screening for rare genetic diseases. In addition, understanding the spectrum of severity requires vast amounts of population and genomic data. We propose recommendations on improving the NBS system and addressing specific demands to grow its capacity by: better defining the criteria by which screening targets are established; financing the NBS system's responsiveness to opportunities for expansion, including engagement and funding from stakeholders; creating a national quality assurance, data, IT, and communications infrastructure; and improving intra-governmental communications. While our recommendations may be specific to the United States, the underlying issues should be considered when working to improve NBS programs globally.

Ethical Issues Surrounding Newborn Screening.

It would be difficult to overestimate the importance of persistent, thoughtful parents and their importance in the development of treatments for their children's rare disorders. Almost a century ago in Norway, observant parents led a brilliant young physician-scientist to his discovery of the underlying cause of their children's profound developmental delay-i.e., phenylketonuria, or PKU. Decades later, in a recovering war-ravaged Britain, an equally persistent mother pressed the scientists at Birmingham Children's Hospital to find a way to treat her seriously damaged daughter, Sheila, who suffered from PKU. Living on the financial edge, this mother insisted that Bickel and colleagues develop such a diet, and she volunteered Sheila to be the patient in the trial. The scientists concluded that the low phenylalanine diet helped but needed to be started very early-so, newborn screening was born to permit the implementation of this. Many steps brought us to where we are today, but these courageous parents made it all begin.

Maximizing the Benefit of Life-Saving Treatments for Pompe Disease, Spinal Muscular Atrophy, and Duchenne Muscular Dystrophy Through Newborn Screening: Essential Steps.

IMPORTANCE: Newborn screening (NBS) identifies infants with specific congenital disorders for which earlier intervention cannot only prevent a lifetime of chronic disability but also, most importantly, save lives. In this article, we discuss complexities associated with NBS processes in the United States, with a focus on challenges in neuromuscular disorders. OBSERVATIONS: As new interventions for neuromuscular disorders become available, the clinical community must prepare to overcome the challenges of adding new diseases to screening panels and understand the rigorous evidence review at the federal level and the complex process of state-level implementation. In this regard, NBS programs for Pompe disease and spinal muscular atrophy can guide the path of Duchenne muscular dystrophy and other neuromuscular disorders as future candidates for NBS. CONCLUSIONS AND RELEVANCE: The availability of advanced screening methods, the emergence of effective treatment, and the support of professional organizations may facilitate the expansion of NBS, such that an increasing number of infants can be identified in the newborn period who will benefit from life-saving interventions.

Including ELSI research questions in newborn screening pilot studies.

BACKGROUND: The evidence review processes for adding new conditions to state newborn screening (NBS) panels rely on data from pilot studies aimed at assessing the potential benefits and harms of screening. However, the consideration of ethical, legal, and social implications (ELSI) of screening within this research has been limited. This paper outlines important ELSI issues related to newborn screening policy and practices as a resource to help researchers integrate ELSI into NBS pilot studies. APPROACH: Members of the Bioethics and Legal Workgroup for the Newborn Screening Translational Research Network facilitated a series of professional and public discussions aimed at engaging NBS stakeholders to identify important existing and emerging ELSI challenges accompanying NBS. RESULTS: Through these engagement activities, we identified a set of key ELSI questions related to (1) the types of results parents may receive through newborn screening and (2) the initiation and implementation of NBS for a condition within the NBS system. CONCLUSION: Integrating ELSI questions into pilot studies will help NBS programs to better understand the potential impact of screening for a new condition on newborns and families, and make crucial policy decisions aimed at maximized benefits and mitigating the potential negative medical or social implications of screening.

Treatment Algorithm for Infants Diagnosed with Spinal Muscular Atrophy through Newborn Screening.

BACKGROUND: Spinal muscular atrophy (SMA) is an autosomal recessive disease characterized by the degeneration of alpha motor neurons in the spinal cord, leading to muscular atrophy. SMA is caused by deletions or mutations in the survival motor neuron 1 gene (SMN1). In humans, a nearly identical copy gene, SMN2, is present. Because SMN2 has been shown to decrease disease severity in a dose-dependent manner, SMN2 copy number is predictive of disease severity. OBJECTIVE: To develop a treatment algorithm for SMA-positive infants identified through newborn screening based upon SMN2 copy number. METHODS: A working group comprised of 15 SMA experts participated in a modified Delphi process, moderated by a neutral third-party expert, to develop treatment guidelines. RESULTS: The overarching recommendation is that all infants with two or three copies of SMN2 should receive immediate treatment (n = 13). For those infants in which immediate treatment is not recommended, guidelines were developed that outline the timing and appropriate screens and tests to be used to determine the timing of treatment initiation. CONCLUSIONS: The identification SMA affected infants via newborn screening presents an unprecedented opportunity for achievement of maximal therapeutic benefit through the administration of treatment pre-symptomatically. The recommendations provided here are intended to help formulate treatment guidelines for infants who test positive during the newborn screening process.

From a Single Child to Uniform Newborn Screening: My Lucky Life in Pediatric Medical Genetics.

Mike, a memorable young patient with untreated phenylketonuria, as well as others affected by genetic disorders that could be treated if diagnosed in infancy, launched my six-decade career. This autobiographical article reflects on my childhood, early research, and professional experiences in pediatric genetics. My laboratory research focused on inborn errors of metabolism, including the glycogen storage diseases. My effort to organize newborn screening through the recommended uniform screening panel shaped and standardized newborn screening nationwide. Looking ahead, the expansion of whole-genome and whole-exome sequencing into newborn screening raises ethical and policy issues regarding informed consent procedures and the storage and use of residual blood spots.

Duchenne Muscular Dystrophy Newborn Screening, a Case Study for Examining Ethical and Legal Issues for Pilots for Emerging Disorders: Considerations and Recommendations.

Duchenne muscular dystrophy (DMD/Duchenne) is one of the ten most severe and common pediatric genetic diseases and affects an estimated 1 in every 5000 male births. While Duchenne is a 100% fatal disease, the clinical community has demonstrated that immediate identification and early clinical interventions can add years, even decades to an individual's life span. In anticipation of the changing therapeutic landscape for the Duchenne community, Parent Project Muscular Dystrophy established a newborn screening (NBS) initiative. This initiative included a Bioethics and Legal Issues Workgroup to consider the bioethics and legal issues of NBS for Duchenne. The workgroup's discussion focused only on Duchenne NBS and met through conference calls over a one-year period of time seeking consensus on various identified issues. This article reports on the findings and recommendations from that workgroup.

Newborn screening for Duchenne muscular dystrophy in China: follow-up diagnosis and subsequent treatment.

BACKGROUND: Newborn screening for Duchenne muscular dystrophy (DMD) is currently being initiated in Zhejiang Province, China and is under consideration in other countries, including the United States. As China begins to implement DMD newborn screening (DMD-NBS), there is ongoing discussion regarding the steps forward for follow up care of positively identified patients as well as false positive and false negative results. DATA SOURCES: Relevant papers related to DMD-NBS, and NBS in China were reviewed in PubMed. RESULTS: The current state of DMD-NBS is discussed, along with the steps needed to effectively screen infants for this disease in China, recommendations for establishment of follow up care in patients with positive and negative screens, and measurement of patient outcomes. CONCLUSIONS: Zhejiang Province, China is ready to implement DMD-NBS. Future challenges that exist for this program, and other countries, include the ability to track patients, assist with access to care, and ensure adequate follow-up care according to evidence-based guidelines. In addition, China's large rural population, lack of specialty providers, and difficulty in educating patients regarding the benefits of treatment create challenges that will need to be addressed.

Phenylketonuria Scientific Review Conference: state of the science and future research needs.

New developments in the treatment and management of phenylketonuria (PKU) as well as advances in molecular testing have emerged since the National Institutes of Health 2000 PKU Consensus Statement was released. An NIH State-of-the-Science Conference was convened in 2012 to address new findings, particularly the use of the medication sapropterin to treat some individuals with PKU, and to develop a research agenda. Prior to the 2012 conference, five working groups of experts and public members met over a 1-year period. The working groups addressed the following: long-term outcomes and management across the lifespan; PKU and pregnancy; diet control and management; pharmacologic interventions; and molecular testing, new technologies, and epidemiologic considerations. In a parallel and independent activity, an Evidence-based Practice Center supported by the Agency for Healthcare Research and Quality conducted a systematic review of adjuvant treatments for PKU; its conclusions were presented at the conference. The conference included the findings of the working groups, panel discussions from industry and international perspectives, and presentations on topics such as emerging treatments for PKU, transitioning to adult care, and the U.S. Food and Drug Administration regulatory perspective. Over 85 experts participated in the conference through information gathering and/or as presenters during the conference, and they reached several important conclusions. The most serious neurological impairments in PKU are preventable with current dietary treatment approaches. However, a variety of more subtle physical, cognitive, and behavioral consequences of even well-controlled PKU are now recognized. The best outcomes in maternal PKU occur when blood phenylalanine (Phe) concentrations are maintained between 120 and 360 µmol/L before and during pregnancy. The dietary management treatment goal for individuals with PKU is a blood Phe concentration between 120 and 360 µmol/L. The use of genotype information in the newborn period may yield valuable insights about the severity of the condition for infants diagnosed before maximal Phe levels are achieved. While emerging and established genotype-phenotype correlations may transform our understanding of PKU, establishing correlations with intellectual outcomes is more challenging. Regarding the use of sapropterin in PKU, there are significant gaps in predicting response to treatment; at least half of those with PKU will have either minimal or no response. A coordinated approach to PKU treatment improves long-term outcomes for those with PKU and facilitates the conduct of research to improve diagnosis and treatment. New drugs that are safe, efficacious, and impact a larger proportion of individuals with PKU are needed. However, it is imperative that treatment guidelines and the decision processes for determining access to treatments be tied to a solid evidence base with rigorous standards for robust and consistent data collection. The process that preceded the PKU State-of-the-Science Conference, the conference itself, and the identification of a research agenda have facilitated the development of clinical practice guidelines by professional organizations and serve as a model for other inborn errors of metabolism.

Appropriateness of newborn screening for α1-antitrypsin deficiency.

OBJECTIVE: The Alpha-1 Foundation convened a workshop to consider the appropriateness of newborn screening for α-1-antitrypsin (AAT) deficiency. METHODS: A review of natural history and technical data was conducted. RESULTS: Homozygous ZZ AAT deficiency is a common genetic disease occurring in 1 in 2000 to 3500 births; however, it is underrecognized and most patients are undiagnosed. AAT deficiency can cause chronic liver disease, cirrhosis, and liver failure in children and adults, and lung disease in adults. The clinical course is highly variable. Some neonates present with cholestatic hepatitis and some children require liver transplantation, but many patients remain well into adulthood. Some adults develop emphysema. There is no treatment for AAT liver disease, other than supportive care and liver transplant. There are no data on the effect of early diagnosis on liver disease. Avoidance of smoking is of proven benefit to reduce future lung disease, as is protein replacement therapy. Justifying newborn screening with the aim of reducing smoking and reducing adult lung disease-years in the future would be a significant paradigm shift for the screening field. Recent passage of the Genetic Information Nondiscrimination Act (GINA) and the Affordable Care Act may have a major effect on reducing the psychosocial and financial risks of newborn screening because many asymptomatic children would be identified. Data on the risk-benefit ratio of screening in the new legal climate are lacking. CONCLUSIONS: Workshop participants recommended a series of pilot studies focused on generating new data on the risks and benefits of newborn screening.

Expanding research to provide an evidence base for nutritional interventions for the management of inborn errors of metabolism.

A trans-National Institutes of Health initiative, Nutrition and Dietary Supplement Interventions for Inborn Errors of Metabolism (NDSI-IEM), was launched in 2010 to identify gaps in knowledge regarding the safety and utility of nutritional interventions for the management of inborn errors of metabolism (IEM) that need to be filled with evidence-based research. IEM include inherited biochemical disorders in which specific enzyme defects interfere with the normal metabolism of exogenous (dietary) or endogenous protein, carbohydrate, or fat. For some of these IEM, effective management depends primarily on nutritional interventions. Further research is needed to demonstrate the impact of nutritional interventions on individual health outcomes and on the psychosocial issues identified by patients and their families. A series of meetings and discussions were convened to explore the current United States' funding and regulatory infrastructure and the challenges to the conduct of research for nutritional interventions for the management of IEM. Although the research and regulatory infrastructure are well-established, a collaborative pathway that includes the professional and advocacy rare disease community and federal regulatory and research agencies will be needed to overcome current barriers.

Strategies for implementing screening for critical congenital heart disease.

BACKGROUND: Although newborn screening for critical congenital heart disease (CCHD) was recommended by the US Health and Human Services Secretary's Advisory Committee on Heritable Disorders in Newborns and Children to promote early detection, it was deemed by the Secretary of the HHS as not ready for adoption pending an implementation plan from HHS agencies. OBJECTIVE: To develop strategies for the implementation of safe, effective, and efficient screening. METHODS: A work group was convened with members selected by the Secretary's Advisory Committee on Heritable Disorders in Newborns and Children, the American Academy of Pediatrics, the American College of Cardiology Foundation, and the American Heart Association. RESULTS: On the basis of published and unpublished data, the work group made recommendations for a standardized approach to screening and diagnostic follow-up. Key issues for future research and evaluation were identified. CONCLUSIONS: The work-group members found sufficient evidence to begin screening for low blood oxygen saturation through the use of pulse-oximetry monitoring to detect CCHD in well-infant and intermediate care nurseries. Research is needed regarding screening in special populations (eg, at high altitude) and to evaluate service infrastructure and delivery strategies (eg, telemedicine) for nurseries without on-site echocardiography. Public health agencies will have an important role in quality assurance and surveillance. Central to the effectiveness of screening will be the development of a national technical assistance center to coordinate implementation and evaluation of newborn screening for CCHD.