Screening of Newborns for Disorders with High Benefit-Risk Ratios Should Be Mandatory

Newborn Screening by DNA-First: Systematic Evaluation of the Eligibility of Inherited Metabolic Disorders Based on Treatability

The biomarker-based Dutch Newborn Screening (NBS) panel (as of 2024) comprises 19 inherited metabolic disorders (IMDs). With the use of next-generation sequencing (NGS) as a first-tier screen, NBS could expand to include IMDs that lack a reliable biochemical footprint in dried blood spots, while also reducing secondary findings. To be eligible for inclusion in NBS, an IMD needs to fulfill the Wilson and Jungner criteria, with treatability being one of the most important criteria. In this study, we aimed to identify IMDs eligible for DNA-first NBS when considering only treatability in the context of NBS as a prerequisite. First, three independent reviewers performed a systematic literature review of the 1459 genotypic IMDs and their causative gene(s), as described in the International Classification of Inherited Metabolic Disorders (dated 1 February 2021), applying 16 criteria to exclude non-treatable disorders. Eligible disorders were then discussed in three online meetings with a project group of clinical laboratory geneticists, medical laboratory specialists specialized in IMD, and pediatricians with expertise in IMDs. Based on treatability, we identified 100 genes, causing 95 IMDs, as eligible for NBS, including 42 causal genes for the IMDs in the current biomarker-based NBS. The other 58 genes are primarily associated with treatable defects in amino acid metabolism and fatty acid oxidation. Other IMDs were excluded, most often because of insufficient literature. As the evaluation of treatability was not straightforward, we recommend the development of standardized treatability scores for the inclusion of IMDs in NBS.

"Using dried blood spots beyond newborn screening - is Hong Kong ready?": navigating the intersection of innovation readiness, privacy concerns, and Chinese parenting culture

BACKGROUND

Newborn screening programmes offer an opportunity to obtain dried blood spots (DBS) cards that contain a wealth of biological information that can be stored for long periods and have potential benefits for research and quality assurance. However, the storage and secondary uses of DBS cards pose numerous ethical, clinical, and social challenges. Empirical research exploring public attitudes is central to public policy planning as it can indicate whether or not there is broad public support, define public concerns, and ascertain the circumstances required to alleviate concerns and ensure support. This study aims to describe the clinical experience and attitudes towards newborn screening and investigate the perceptions and expectations of Hong Kong parents and healthcare providers regarding the retention of DBS cards and their usage for research.

METHODS

We conducted semi-structured in-person interviews with 20 parents and healthcare providers in Hong Kong. Thematic analysis was conducted.

RESULTS

Awareness of the significant research value of secondary uses of dried blood spot cards is low. Parents and healthcare providers support the storage and secondary uses of DBS cards with some concerns, including privacy and confidentiality breaches, the risk of discrimination or stigmatisation based on genetic information, and their inability to oversee the use of their child's biospecimen. Parents, however, prioritise their child's health over privacy concerns and support identifiable storage using pseudonymity to gain more information about their children's health.

CONCLUSION

Child information takes precedence over potential concerns over privacy, underscoring the significance of engaging patients and the public in shaping public policy related to biobanking and healthcare research, in line with cultural and social values.

Do young adults complete health care proxies before anesthesia?

Background

Health care proxy (HCP) completion rates by older adults are relatively low; however, not much is known about proxy completion rates by younger adults.

Objectives

This study aimed to identify HCP completion rates amongst 18-21 year old young adults without intellectual disabilities admitted to a pediatric hospital peri-anesthesia care unit (PACU) and determine whether there was an association with any demographic factors.

Methods

Retrospective chart review was performed to describe demographic variables, presence of HCP, and relationship to proxy. The relationship between demographic groups and HCP completion was analyzed by chi-square analysis for categorical variables and student t-test for continuous variables.

Results

Overall, 31.4 % (128/408) of patients completed an HCP, and younger patients were more likely to have done so. Analysis showed no statistically significant relationship between other demographic variables and HCP completion. A majority of patients identified a parent as their proxy.

Conclusion

Less than one third of young adult patients admitted to a children's hospital perioperative care unit completed a health care proxy. Other than age, there was no statistically significant difference in demographic variables between those who completed and did not complete a health care proxy. Further research is needed to validate these findings in other clinical settings and drive targeted initiatives to increase advance care planning among young adult patients.

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.

Machine Learning and Prediction in Fetal, Infant, and Toddler Neuroimaging: A Review and Primer

Predictive models in neuroimaging are increasingly designed with the intent to improve risk stratification and support interventional efforts in psychiatry. Many of these models have been developed in samples of children school-aged or older. Nevertheless, despite growing evidence that altered brain maturation during the fetal, infant, and toddler (FIT) period modulates risk for poor mental health outcomes in childhood, these models are rarely implemented in FIT samples. Applications of predictive modeling in children of these ages provide an opportunity to develop powerful tools for improved characterization of the neural mechanisms underlying development. To facilitate the broader use of predictive models in FIT neuroimaging, we present a brief primer and systematic review on the methods used in current predictive modeling FIT studies. Reflecting on current practices in more than 100 studies conducted over the past decade, we provide an overview of topics, modalities, and methods commonly used in the field and under-researched areas. We then outline ethical and future considerations for neuroimaging researchers interested in predicting health outcomes in early life, including researchers who may be relatively new to either advanced machine learning methods or using FIT data. Altogether, the last decade of FIT research in machine learning has provided a foundation for accelerating the prediction of early-life trajectories across the full spectrum of illness and health.

Harmonization of Newborn Screening Results for Pompe Disease and Mucopolysaccharidosis Type I

In newborn screening, false-negative results can be disastrous, leading to disability and death, while false-positive results contribute to parental anxiety and unnecessary follow-ups. Cutoffs are set conservatively to prevent missed cases for Pompe and MPS I, resulting in increased falsepositive results and lower positive predictive values. Harmonization has been proposed as a way to minimize false-negative and false-positive results and correct for method differences, so we harmonized enzyme activities for Pompe and MPS I across laboratories and testing methods (Tandem Mass Spectrometry (MS/MS) or Digital Microfluidics (DMF)). Participating states analyzed proofof- concept calibrators, blanks, and contrived specimens and reported enzyme activities, cutoffs, and other testing parameters to Tennessee. Regression and multiples of the median were used to harmonize the data. We observed varied cutoffs and results. Six of seven MS/MS labs reported enzyme activities for one specimen for MPS I marginally above their respective cutoffs with results classified as negative, whereas all DMF labs reported this specimen's enzyme activity below their respective cutoffs with results classified as positive. Reasonable agreement in enzyme activities and cutoffs was achieved with harmonization; however, harmonization does not change how a value would be reported as this is dependent on the placement of cutoffs.

Sex-specific newborn screening for X-linked adrenoleukodystrophy

Males with X-linked adrenoleukodystrophy (ALD) are at high risk for developing adrenal insufficiency and/or progressive leukodystrophy (cerebral ALD) at an early age. Pathogenic variants in ABCD1 result in elevated levels of very long-chain fatty acids (VLCFA), including C26:0-lysophosphatidylcholine (C26:0-LPC). Newborn screening for ALD enables prospective monitoring and timely therapeutic intervention, thereby preventing irreversible damage and saving lives. The Dutch Health Council recommended to screen only male newborns for ALD without identifying untreatable conditions associated with elevated C26:0-LPC, like Zellweger spectrum disorders and single peroxisomal enzyme defects. Here, we present the results of the SCAN (Screening for ALD in the Netherlands) study which is the first sex-specific newborn screening program worldwide. Males with ALD are identified based on elevated C26:0-LPC levels, the presence of one X-chromosome and a variant in ABCD1, in heel prick dried bloodspots. Screening of 71 208 newborns resulted in the identification of four boys with ALD who, following referral to the pediatric neurologist and confirmation of the diagnosis, enrolled in a long-term follow-up program. The results of this pilot show the feasibility of employing a boys-only screening algorithm that identifies males with ALD without identifying untreatable conditions. This approach will be of interest to countries that are considering ALD newborn screening but are reluctant to identify girls with ALD because for girls there is no direct health benefit. We also analyzed whether gestational age, sex, birth weight and age at heel prick blood sampling affect C26:0-LPC concentrations and demonstrate that these covariates have a minimal effect.

Target Diseases for Neonatal Screening in Germany

BACKGROUND

Neonatal screening in Germany currently comprises 19 congenital diseases, 13 of which are metabolic diseases. Approximately one in 1300 newborns suffers from one of these target diseases. Early diagnosis and treatment enable the affected children to undergo better development and even, in many cases, to have a normal life.

METHODS

This review is based on pertinent publications retrieved by a selective search in the PubMed and Embase databases.

RESULTS

Positive screening findings are confirmed in approximately one out of five newborns. The prompt evaluation of suspected diagnoses is essential, as treatment for some of these diseases must be initiated immediately after birth to prevent longterm sequelae. The most commonly identified diseases are primary hypothyroidism (1:3338), phenylketonuria/hyperphenylalaninemia (1 : 5262), cystic fibrosis (1 : 5400), and medium-chain acyl-CoA dehydrogenase deficiency (1 : 10 086). Patient numbers are rising as new variants of the target diseases are being identified, and treatments must be adapted to their heterogeneous manifestations. Precise diagnosis and the planning of treatment, which is generally lifelong, are best carried out in a specialized center.

CONCLUSION

Improved diagnosis and treatment now prolong the lives of many patients with congenital diseases. The provision of appropriate long-term treatment extending into adulthood will be a central structural task for screening medicine in the future.

A New Approach to Objectively Evaluate Inherited Metabolic Diseases for Inclusion on Newborn Screening Programmes

Newborn screening (NBS) programmes are essential in the diagnosis of inherited metabolic diseases (IMDs) and for access to disease modifying treatment. Most European countries follow the World Health Organisation (WHO) criteria to determine which disorders are appropriate for screening at birth; however, these criteria are interpreted and implemented by individual countries differently, creating disparities. Advances in research and diagnostics, together with the promise of new treatments, offer new possibilities to accelerate the expansion of evidence-based screening programmes. A novel and robust algorithm was built to objectively assess and prioritise IMDs for inclusion in NBS programmes. The Wilson and Jungner classic screening principles were used as a foundation to develop individual and measurable criteria. The proposed algorithm is a point-based system structured upon three pillars: condition, screening, and treatment. The algorithm was tested by applying the six IMDs currently approved in the United Kingdom NBS programme. The algorithm generates a weight-based score that could be used as the first step in the complex process of evaluating disorders for inclusion on NBS programmes. By prioritising disorders to be further evaluated, individual countries are able to assess the economic, societal and political aspects of a potential screening programme.

Analytical Validation of Familial Hypercholesterolemia Biomarkers in Dried Blood Spots

Heterozygous familial hypercholesterolemia (HeFH) is a common, treatable genetic disorder characterized by premature atherosclerosis and cardiovascular disease, yet the majority of affected individuals remain undiagnosed. Newborn screening could play a role in identification of at-risk individuals and provide an opportunity for early intervention, prior to the onset of symptoms. The objective of this study was to develop and validate assays for quantification of candidate HeFH biomarkers in dried blood spots (DBS). Commercially available enzyme assay kits for quantification of serum total cholesterol (TC) and low-density lipoprotein-cholesterol (LDL-C) were modified for high-throughput analysis of DBS. Apolipoprotein B (ApoB) concentrations in DBS were measured using an immunoassay with modifications from published studies. All three assays were validated according to the College of American Pathologists guidelines for clinical laboratories. The performance of TC, LDL-C, and ApoB assays was assessed by precision, recovery, limit of quantification (LOQ) and linearity. Precision studies yielded coefficients of variation (CV) of less than 15%, with recovery greater than 75% for all three assays. The determined LOQ and linearity were comparable to serum-based assays. In a direct comparison between serum and DBS concentrations, positive correlations were demonstrated for TC, LDL-C, and ApoB. Additionally, the initial evaluation of the three biomarker concentrations within the unaffected population was similar to values obtained in previous published studies. This study reports on methods for quantification of TC, LDL-C, and ApoB in DBS. Assay validation results were within acceptable limits for newborn screening. This is an important first step toward the identification of newborns with HeFH.

Cord blood metabolic signatures predictive of childhood overweight and rapid growth

INTRODUCTION

Metabolomics may identify biological pathways predisposing children to the risk of overweight and obesity. In this study, we have investigated the cord blood metabolic signatures of rapid growth in infancy and overweight in early childhood in four European birth cohorts.

METHODS

Untargeted liquid chromatography-mass spectrometry metabolomic profiles were measured in cord blood from 399 newborns from four European cohorts (ENVIRONAGE, Rhea, INMA and Piccolipiu). Rapid growth in the first year of life and overweight in childhood was defined with reference to WHO growth charts. Metabolome-wide association scans for rapid growth and overweight on over 4500 metabolic features were performed using multiple adjusted logistic mixed-effect models and controlling the false discovery rate (FDR) at 5%. In addition, we performed a look-up analysis of 43 pre-annotated metabolites, previously associated with birthweight or rapid growth.

RESULTS

In the Metabolome-Wide Association Study analysis, we identified three and eight metabolites associated with rapid growth and overweight, respectively, after FDR correction. Higher levels of cholestenone, a cholesterol derivative produced by microbial catabolism, were predictive of rapid growth (p = 1.6 × 10-3). Lower levels of the branched-chain amino acid (BCAA) valine (p = 8.6 × 10-6) were predictive of overweight in childhood. The area under the receiver operator curve for multivariate prediction models including these metabolites and traditional risk factors was 0.77 for rapid growth and 0.82 for overweight, compared with 0.69 and 0.69, respectively, for models using traditional risk factors alone. Among the 43 pre-annotated metabolites, seven and five metabolites were nominally associated (P < 0.05) with rapid growth and overweight, respectively. The BCAA leucine, remained associated (1.6 × 10-3) with overweight after FDR correction.

CONCLUSION

The metabolites identified here may assist in the identification of children at risk of developing obesity and improve understanding of mechanisms involved in postnatal growth. Cholestenone and BCAAs are suggestive of a role of the gut microbiome and nutrient signalling respectively in child growth trajectories.

An ethical analysis of divergent clinical approaches to the application of genetic testing for autism and schizophrenia

Genetic testing to identify genetic syndromes and copy number variants (CNVs) via whole genome platforms such as chromosome microarray (CMA) or exome sequencing (ES) is routinely performed clinically, and is considered by a variety of organizations and societies to be a "first-tier" test for individuals with developmental delay (DD), intellectual disability (ID), or autism spectrum disorder (ASD). However, in the context of schizophrenia, though CNVs can have a large effect on risk, genetic testing is not typically a part of routine clinical care, and no clinical practice guidelines recommend testing. This raises the question of whether CNV testing should be similarly performed for individuals with schizophrenia. Here we consider this proposition in light of the history of genetic testing for ID/DD and ASD, and through the application of an ethical analysis designed to enable robust, accountable and justifiable decision-making. Using a systematic framework and application of relevant bioethical principles (beneficence, non-maleficence, autonomy, and justice), our examination highlights that while CNV testing for the indication of ID has considerable benefits, there is currently insufficient evidence to suggest that overall, the potential harms are outweighed by the potential benefits of CNV testing for the sole indications of schizophrenia or ASD. However, although the application of CNV tests for children with ASD or schizophrenia without ID/DD is, strictly speaking, off-label use, there may be clinical utility and benefits substantive enough to outweigh the harms. Research is needed to clarify the harms and benefits of testing in pediatric and adult contexts. Given that genetic counseling has demonstrated benefits for schizophrenia, and has the potential to mitigate many of the potential harms from genetic testing, any decisions to implement genetic testing for schizophrenia should involve high-quality evidence-based genetic counseling.

Spectrum of PAH gene mutations in 1547 phenylketonuria patients from Iran: a comprehensive systematic review

As one of the highest prevalence rates in the world, the prevalence of Phenylketonuria (PKU) in Iran has been estimated at 16.5 per 100,000 neonates. The objective of this study was to evaluate the spectrum and frequency of mutations of the phenylalanine hydroxylase (PAH) gene in Iranian PKU patients. A systematic review was carried out on previous studies on PAH gene mutations in Iranian PKU patients. A complete search was carried out on the on-line databases of Scopus, Web of Science, PubMed/Medline, ProQuest, Science Direct, Magiran, SID and the search engine Google Scholar. The keywords of Phenylketonuria, PKU, Phenylalanine Hydroxylase, PAH, and Iran, as well as their Persian equivalents, in all possible combinations were used. Finally, a total of 21 eligible articles with a sample size of 1547 Iranian PKU patients, published between 2003 and 2020, were included in our systematic review. A total of 129 different PAH gene mutations including, IVS10-11G > A (c.1066-11G > A) (19.23%), p.R261Q (c.782G > A) (7.63%), p.P281L (c.842C > T) (6.24%), IVS2 + 5G > C (c.168 + 5G > C) (5.75%), p.R243* (c.727C > T) (3.59%), IVS9 + 5G > A (c.969 + 5G > A) (2.84%), p.R176* (c.526C > T) (2.42%), p.Lys363Nfs*37 (c.1089delG) (2.13%), IVS11 + 1G > C (c.1199 + 1G > C) (2.07%) and p.L48S (c.143 T > C) (2.04%) were identified. The spectrum and frequency of mutations observed in Iran were closer to those observed in the Mediterranean countries. Our results are valuable in planning panel-based studies in provinces with incomplete data on PAH gene mutations. This study is a good reference for genetic counselors and physicians who advise couples in making decisions to maintain or terminate a pregnancy.

Extreme phenotypes approach to investigate host genetics and COVID-19 outcomes

COVID-19 comprises clinical outcomes of SARS-CoV-2 infection and is highly heterogeneous, ranging from asymptomatic individuals to deceased young adults without comorbidities. There is growing evidence that host genetics play an important role in COVID-19 severity, including inborn errors of immunity, age-related inflammation and immunosenescence. Here we present a brief review on the known order of events from infection to severe system-wide disturbance due to COVID-19 and summarize potential candidate genes and pathways. Finally, we propose a strategy of subject's ascertainment based on phenotypic extremes to take part in genomic studies and elucidate intrinsic risk factors involved in COVID-19 severe outcomes.

Scientific Citizenship’s Youngest Domain: Function Creep in Norway’s Newborn Screening Programme

Newborn screening (NBS) for inborn errors of metabolism and other serious conditions with onset during infancy is a widespread public health initiative. Like other screening programmes, it aims to discover and treat a disease before effects manifest themselves. Recently, there have been two prominent changes in NBS: a substantial increase in the number of conditions screened for and growing attention to secondary use of residual newborn blood spots. Here, we analyse how this latter change has transpired in Norway.

In 2018, Norway’s parliament sanctioned the secondary use of NBS samples for epidemiological research unrelated to NBS. This broadened the programme’s scope, co-opting it for research purposes, making samples available for inclusion in Norway’s biobanking strategy. We argue that this transformation is a case of function creep, whereby the function of screening samples is expanded to serve purposes other than helping newborns. The process provided only minimal involvement from ordinary citizens, but it transformed screened infants into potential scientific citizens. Henceforth, all future generations of Norwegians must choose to stay in or opt out of biobank research when they turn sixteen. Additionally, consenting to this research may occasion a second form of function creep, as ‘actionable findings’ are fed back to participants.

What Do People Know About the Heritability of Sleep?

STUDY OBJECTIVES

Twin studies have provided data about the relative weight of genetic and environmental factors on sleep variables over the last few decades. However, heritability is a non-intuitive concept and it is often misunderstood even amongst the scientific community. This study aimed to analyze: (1) understanding of the meaning of heritability of insomnia; (2) the accuracy of estimations of heritability in the general population regarding three sleep traits (sleep duration, sleep quality and insomnia); (3) perceptions of the effectiveness of different treatments for insomnia depending on how the disorder is presented (i.e. having an environmental or genetic etiology) and whether the subject's estimate of genetic influence on sleep traits impacted beliefs about the effectiveness of different treatments.

METHODS

Participants (N = 3658) completed a survey which included: questions about general genetic knowledge; a specific question about the meaning of heritability; estimates of heritability of three different sleep traits; and the effectiveness of different treatments for insomnia depending on how the etiology of this condition was presented.

RESULTS

Fewer than 25% of the participants selected the correct description of the heritability of insomnia. Almost half of the sample incorrectly believed that heritability refers to the chance of passing a disorder onto their children. We also found that participants provided different estimates for the effectiveness of different treatments depending on the presumed etiology of the disorder.

CONCLUSION

Most people do not have accurate knowledge about the concept of heritability. People's assumptions about the etiology of a disorder may influence which treatments they consider most effective.

Local deliberative approach to the bioethical controversies: An opportunity for the proper implementation of neonatal screening

Introduction: The controversial characteristics of neonatal screening influenced by bioethical considerations make its implementation complex. Colombia is not an exception in this sense and local circumstances complicate the panorama. Objective: To establish how bioethical controversies on neonatal screening are approached at a local level as a basis for deliberating on the must-be of this activity in Colombia. Materials and methods: A survey immersed in an interpretative investigation with descriptive and deliberative components of analysis was applied to approach the values exposed by officials of the Colombian Instituto Nacional de Salud. Results: The compulsory offer of screening by the nation, regardless of its opportunity cost and the consent for the use in research of results and residual samples, were not controversial, but, in contrast, the type of information and the consent to authorize screening did arise controversy. The more experienced officials preferred mandatory screening (17.7 vs. 11.79 years on average, p=0.007). Surprisingly, despite the risk of discrimination, keeping the neonate as the purpose, there was agreement on giving all the information to parents and medical records. Another controversial aspect was the follow-up of cases without hiding their identification where officials with more experience in bioethical aspects preferred the use of codes (4.5 vs. 1.26 years on average, p=0.009). In this context, strategies such as informed dissent, specialized advice or public health programs that appreciate diversity would allow to rescue even seemingly opposite values. Conclusion: A local approach regarding what ought to be in neonatal screening based on a deliberative bioethical perspective allowed to present an implementation proposal for this activity

Second-Tier Next Generation Sequencing Integrated in Nationwide Newborn Screening Provides Rapid Molecular Diagnostics of Severe Combined Immunodeficiency

Severe combined immunodeficiency (SCID) and other T cell lymphopenias can be detected during newborn screening (NBS) by measuring T cell receptor excision circles (TRECs) in dried blood spot (DBS) DNA. Second tier next generation sequencing (NGS) with an amplicon based targeted gene panel using the same DBS DNA was introduced as part of our prospective pilot research project in 2015. With written parental consent, 21 000 newborns were TREC-tested in the pilot. Three newborns were identified with SCID, and disease-causing variants in IL2RG, RAG2, and RMRP were confirmed by NGS on the initial DBS DNA. The molecular findings directed follow-up and therapy: the IL2RG-SCID underwent early hematopoietic stem cell transplantation (HSCT) without any complications; the leaky RAG2-SCID received prophylactic antibiotics, antifungals, and immunoglobulin infusions, and underwent HSCT at 1 year of age. The child with RMRP-SCID had complete Hirschsprung disease and died at 1 month of age. Since January 2018, all newborns in Norway have been offered NBS for SCID using 1st tier TRECs and 2nd tier gene panel NGS on DBS DNA. During the first 20 months of nationwide SCID screening an additional 88 000 newborns were TREC tested, and four new SCID cases were identified. Disease-causing variants in DCLRE1C, JAK3, NBN, and IL2RG were molecularly confirmed on day 8, 15, 8 and 6, respectively after birth, using the initial NBS blood spot. Targeted gene panel NGS integrated into the NBS algorithm rapidly delineated the specific molecular diagnoses and provided information useful for management, targeted therapy and follow-up i.e., X rays and CT scans were avoided in the radiosensitive SCID. Second tier targeted NGS on the same DBS DNA as the TREC test provided instant confirmation or exclusion of SCID, and made it possible to use a less stringent TREC cut-off value. This allowed for the detection of leaky SCIDs, and simultaneously reduced the number of control samples, recalls and false positives. Mothers were instructed to stop breastfeeding until maternal cytomegalovirus (CMV) status was determined. Our limited data suggest that shorter time-interval from birth to intervention, may prevent breast milk transmitted CMV infection in classical SCID.

Predominance of the c.648G > T G6PC gene mutation and late complications in Korean patients with glycogen storage disease type Ia

BACKGROUND

Glycogen storage disease (GSD) Ia, caused by mutations in the glucose-6-phosphatase (G6PC) gene, is characterized by hepatomegaly, hypoglycemia, lactic acidosis, dyslipidemia, and hyperuricemia. This study aimed to investigate clinical and molecular features and late complications in Korean patients with GSD Ia.

RESULTS

Fifty-four Korean patients (33 males and 21 females) from 47 unrelated families, who were diagnosed with GSD Ia, based on genetic and biochemical data, between 1999 and 2017, were included in this study. The median age at diagnosis was 3.9 years (range: 5 months to 42 years), and the follow-up period was 8.0 ± 6.8 years. Most patients presented with hepatomegaly during infancy, but hypoglycemic symptoms were not predominant. Genetic analysis showed that all the patients had at least one c.648G > T allele. Homozygous c.648G > T mutations in the G6PC gene were identified in 34 families (72.3%), and compound heterozygotes with c.648G > T were found in the other families. The allele frequency of c.648G > T was 86.2% (81/94), and p.F51S, p.R83H, p.G122D, p.Y128*, p.G222R, and p.T255A were identified. Of 26 adult patients, 14 had multiple hepatic adenomas, and two were diagnosed with hepatocellular carcinoma. Thirteen patients showed renal complications, and seven patients presented gout, despite preventive allopurinol treatment. Twelve patients had osteoporosis, and two patients had pulmonary hypertension. The final heights were 157.9 cm (standard deviation score: - 3.1) in males and 157.8 cm (standard deviation score: - 0.6) in females.

CONCLUSION

In our Korean patients with GSD Ia, the most common mutation in the G6PC gene was c.648G > T, suggesting a founder effect. Because of only mild hypoglycemia, the patients tended to be diagnosed late. Thus, adult patients with GSD Ia eventually developed diverse and serious complications, which indicates a need for careful monitoring and proper management of this disease.

A pediatric perspective on genomics and prevention in the twenty-first century

We present evidence from diverse disciplines and populations to identify the current and emerging role of genomics in prevention from both medical and public health perspectives as well as key challenges and potential untoward consequences of increasing the role of genomics in these endeavors. We begin by comparing screening in healthy populations (newborn screening), with testing in symptomatic populations, which may incidentally identify secondary findings and at-risk relatives. Emerging evidence suggests that variants in genes subject to the reporting of secondary findings are more common than expected in patients who otherwise would not meet the criteria for testing and population testing for variants in these genes may more precisely identify discrete populations to target for various prevention strategies starting in childhood. Conversely, despite its theoretical promise, recent studies attempting to demonstrate benefits of next-generation sequencing for newborn screening have instead demonstrated numerous barriers and pitfalls to this approach. We also examine the special cases of pharmacogenomics and polygenic risk scores as examples of ways genomics can contribute to prevention amongst a broader population than that affected by rare Mendelian disease. We conclude with unresolved questions which will benefit from future investigations of the role of genomics in disease prevention.

The influence of environment and origin on brain resident macrophages and implications for therapy

Microglia are the tissue-resident macrophages of the brain and spinal cord. They are critical players in the development, normal function, and decline of the CNS. Unlike traditional monocyte-derived macrophages, microglia originate from primitive hematopoiesis in the embryonic yolk sac and self-renew throughout life. Microglia also have a unique genetic signature among tissue resident macrophages. Recent studies identify the contributions of both brain environment and developmental history to the transcriptomic identity of microglia. Here we review this emerging literature and discuss the potential implications of origin on microglial function, with particular focus on existing and future therapies using bone-marrow- or stem-cell-derived cells for the treatment of neurological diseases.

Molecular Diagnosis of Inherited Immune Disorders

Primary immunodeficiency diseases are a heterogeneous group of rare inherited disorders of innate or adaptive immune system function. Patients with primary immunodeficiencies typically present with recurrent and severe infections in infancy or young adulthood. More recently, the co-occurrence of autoimmune, benign lymphoproliferative, atopic, and malignant complications has been described. The diagnosis of a primary immunodeficiency disorder requires a thorough assessment of a patient's underlying immune system function. Historically, this has been accomplished at the time of symptomatic presentation by measuring immunoglobulins, complement components, protective antibody titers, or immune cell counts in the peripheral blood. Although these data can be used to critically assess the degree of immune dysregulation in the patient, this approach fall short in at least 2 regards. First, this assessment often occurs after the patient has suffered life-threatening infectious or autoinflammatory complications. Second, these data fail to uncover an underlying molecular cause of the patient's primary immune dysfunction, prohibiting the use of molecularly targeted therapeutic interventions. Within the last decade, the field of primary immunodeficiency diagnostics has been revolutionized by 2 major molecular advancements: (1) the onset of newborn screening in 2008, and (2) the onset of next-generation sequencing in 2010. In this article, the techniques of newborn screening and next-generation sequencing are reviewed and their respective impacts on the field of primary immunodeficiency disorders are discussed with a specific emphasis on severe combined immune deficiency and common variable immune deficiency.

What is in a Name? Parent, Professional and Policy-Maker Conceptions of Consent-Related Language in the Context of Newborn Screening

Newborn bloodspot screening programs are some of the longest running population screening programs internationally. Debate continues regarding the need for parents to give consent to having their child screened. Little attention has been paid to how meanings of consent-related terminology vary among stakeholders and the implications of this for practice. We undertook semi-structured interviews with parents (n = 32), healthcare professionals (n = 19) and policy decision makers (n = 17) in two Canadian provinces. Conceptions of consent-related terms revolved around seven factors within two broad domains, decision-making and information attainment. Decision-making comprised: parent decision authority; voluntariness; parent engagement with decision-making; and the process of enacting choice. Information ascertainment comprised: professional responsibilities (including disclosure of information and time to review); parent responsibilities; and the need for discussion and understanding prior to a decision. Our findings indicate that consent-related terms are variously understood, with substantive implications for practice. We suggest that consent procedures should be explained descriptively, regardless of approach, so there are clear indications of what is expected of parents and healthcare professionals. Support systems are required both to meet the educational needs of parents and families and to support healthcare professionals in delivering information in a manner in keeping with parent needs.

Early Check: translational science at the intersection of public health and newborn screening

Background

Newborn screening (NBS) occupies a unique space at the intersection of translational science and public health. As the only truly population-based public health program in the United States, NBS offers the promise of making the successes of translational medicine available to every infant with a rare disorder that is difficult to diagnose clinically, but for which strong evidence indicates that presymptomatic treatment will substantially improve outcomes. Realistic NBS policy requires data, but rare disorders face a special challenge: Screening cannot be done without supportive data, but adequate data cannot be collected in the absence of large-scale screening. The magnitude and scale of research to provide this expanse of data require working with public health programs, but most do not have the resources or mandate to conduct research.

Methods

To address this gap, we have established Early Check, a research program in partnership with a state NBS program. Early Check provides the infrastructure needed to identify conditions for which there have been significant advances in treatment potential, but require a large-scale, population-based study to test benefits and risks, demonstrate feasibility, and inform NBS policy.

Discussion

Our goal is to prove the benefits of a program that can, when compared with current models, accelerate understanding of diseases and treatments, reduce the time needed to consider inclusion of appropriate conditions in the standard NBS panel, and accelerate future research on new NBS conditions, including clinical trials for investigational interventions.

Trial registration

Clinicaltrials.gov registration #NCT03655223. Registered on August 31, 2018.

The complexity of a monogenic neurodegenerative disease: More than two decades of therapeutic driven research into Niemann-Pick type C disease

Niemann-Pick type C (NP-C) disease is a rare and fatal neurodegenerative disease typified by aberrations in intracellular lipid transport. Cholesterol and other lipids accumulate in the late endosome/lysosome of all diseased cells thereby causing neuronal and visceral atrophy. A cure for NP-C remains elusive despite the extensive molecular advances emanating from the identification of the primary genetic defect in 1997. Penetration of the blood-brain barrier and efficacy in the viscera are prerequisites for effective therapy, however the rarity of NP-C disease is the major impediment to progress. Disease diagnosis is challenging and establishment of appropriate test populations for clinical trials difficult. Fortunately, disease models that span the diversity of microbial and metazoan life have been utilized to advance the quest for a therapy. The complexity of lipid storage in this disorder and in the model systems, has led to multiple theories on the primary disease mechanism and consequently numerous and varied proposed interventions. Here, we conduct an evaluation of these studies.

Ethical issues in pediatric genetic testing and screening

PURPOSE OF REVIEW

Developments in genetic test technologies enable a detailed analysis of the genomes of individuals across the range of human development from embryos to adults with increased precision and lower cost. These powerful technologies raise a number of ethical issues in pediatrics, primarily because of the frequent lack of clinical utility of genetic information, the generation of secondary results and questions over the proper scope of parental authority for testing.

RECENT FINDINGS

Several professional organizations in the fields of genetics and pediatrics have published new guidance on the ethical, legal, and policy issues relevant to genetic testing in children. The roles of predictive testing for adult-onset conditions, the management of secondary findings and the role of informed consent for newborn screening remain controversial. However, research and experience are not demonstrating serious adverse psychosocial impacts from genetic testing and screening in children. The use of these technologies is expanding with the notion that the personal utility of test results, rather than clinical utility, may be sufficient to justify testing.

SUMMARY

The use of microarray and genome sequencing technologies is expanding in the care of children. More deference to parental decision-making is evolving in contexts wherein information and counseling can be made readily available.