Current status of newborn screening worldwide: 2015

Quality considerations and major pitfalls for high throughput DNA-based newborn screening for severe combined immunodeficiency and spinal muscular atrophy

BACKGROUND

Many newborn screening programs worldwide have introduced screening for diseases using DNA extracted from dried blood spots (DBS). In Germany, DNA-based assays are currently used to screen for severe combined immunodeficiency (SCID), spinal muscular atrophy (SMA), and sickle cell disease (SCD).

METHODS

This study analysed the impact of pre-analytic DNA carry-over in sample preparation on the outcome of DNA-based newborn screening for SCID and SMA and compared the efficacy of rapid extraction versus automated protocols. Additionally, the distribution of T cell receptor excision circles (TREC) on DBS cards, commonly used for routine newborn screening, was determined.

RESULTS

Contaminations from the punching procedure were detected in the SCID and SMA assays in all experimental setups tested. However, a careful evaluation of a cut-off allowed for a clear separation of true positive polymerase chain reaction (PCR) amplifications. Our rapid in-house extraction protocol produced similar amounts compared to automated commercial systems. Therefore, it can be used for reliable DNA-based screening. Additionally, the amount of extracted DNA significantly differs depending on the location of punching within a DBS.

CONCLUSIONS

Newborn screening for SMA and SCID can be performed reliably. It is crucial to ensure that affected newborns are not overlooked. Therefore a carefully consideration of potential contaminating factors and the definition of appropriate cut-offs to minimise the risk of false results are of special concern. It is also important to note that the location of punching plays a pivotal role, and therefore an exact quantification of TREC numbers per μl may not be reliable and should therefore be avoided.

Cohort profile: Improved Pregnancy Outcomes via Early Detection (IMPROvED), an International Multicentre Prospective Cohort

Background

Improved Pregnancy Outcomes via Early Detection (IMPROvED) is a multi-centre, European phase IIa clinical study. The primary aim of IMPROvED is to enable the assessment and refinement of innovative prototype preeclampsia risk assessment tests based on emerging biomarker technologies. Here we describe IMPROvED's profile and invite researchers to collaborate.

Methods

A total of 4,038 low-risk nulliparous singleton pregnancies were recruited from maternity units in Ireland (N=1,501), United Kingdom (N=1,108), The Netherlands (N=810), and Sweden (N=619) between November 2013 to August 2017. Participants were interviewed by a research midwife at ~11 weeks (optional visit), ~15 weeks, ~20 weeks, ~34 weeks' gestation (optional visit), and postpartum (within 72-hours following delivery).

Findings to date

Clinical data included information on maternal sociodemographic, medical history, and lifestyle factors collected at ~15 weeks' gestation, and maternal measurements, collected at each study visit. Biobank samples included blood, urine, and hair collected at each study visit throughout pregnancy in all units plus umbilical cord/blood samples collected at birth in Ireland and Sweden. A total of 74.0% (N=2,922) had an uncomplicated pregnancy, 3.1% (N=122) developed preeclampsia, 3.6% (N=143) had a spontaneous preterm birth, and 10.5% (N=416) had a small for gestational age baby. We evaluated a panel of metabolite biomarkers and a panel of protein biomarkers at 15 weeks and 20 weeks' gestation for preeclampsia risk assessment. Their translation into tests with clinical application, as conducted by commercial entities, was hampered by technical issues and changes in test requirements. Work on the panel of proteins was abandoned, while work on the use of metabolite biomarkers for preeclampsia risk assessment is ongoing.

Future plans

In accordance with the original goals of the IMPROvED study, the data and biobank are now available for international collaboration to conduct high quality research into the cause and prevention of adverse pregnancy outcomes.

The clinical spectrum of HbSC sickle cell disease-not a benign condition

Sickle cell disease (SCD) includes a group of heterogenous disorders that result in significant morbidities. HbSS is the most common type of SCD and HbSC is the second most common type of SCD. The prevalence of HbSC disease in the United States and United Kingdom is ~1 in 7174 births and 1 in 6174 births respectively. Despite its frequency, however, HbSC disease has been insufficiently studied and was historically categorized as a more 'mild' form of SCD. We conducted this study of HbSC disease as part of the NHLBI funded Sickle Cell Disease Implementation Consortium (SCDIC). The SCDIC registry included 2282 individuals with SCD, ages 15-45 years of whom 502 (22%) had HbSC disease. Compared with people with sickle cell anaemia (SCA), the study found that people with HbSC disease had a higher frequency of splenomegaly (n (%) = 169 (33.7) vs. 392 (22.1)) and retinopathy (n (%) = 116 (23.1) vs. 189 (10.6)). A Many people with HbSC also had avascular necrosis (n (%) = 112 (22.3)), pulmonary embolism (n (%) = 43 (8.6)) and acute chest syndrome (n (%) = 228 (45.4)) demonstrating significant disease severity. HbSC disease is more clinically severe than was previously recognized and deserves additional evaluation and targeted treatments.

Trajectories of illness uncertainty among parents of children with atypical genital appearance due to differences of sex development

OBJECTIVE

The present study aimed to identify distinct trajectories of parental illness uncertainty among parents of children born with atypical genital appearance due to a difference of sex development over the first year following diagnosis. It was hypothesized that four trajectory classes would emerge, including "low stable," "high stable," "decreasing," and "increasing" classes, and that select demographic, familial, and medical factors would predict these classes.

METHODS

Participants included 56 mothers and 43 fathers of 57 children born with moderate to severe genital atypia. Participants were recruited from eleven specialty clinics across the U.S. Growth mixture modeling (GMM) approaches, controlling for parent dyad clustering, were conducted to examine classes of parental illness uncertainty ratings over time.

RESULTS

A three-class GMM was identified as the best-fitting model. The three classes were interpreted as "moderate stable" (56.8%), "low stable" (33.0%), and "declining" (10.3%). Findings suggest possible diagnostic differences across trajectories.

CONCLUSIONS

Findings highlight the nature of parents' perceptions of ambiguity and uncertainty about their child's diagnosis and treatment the year following their child's birth/diagnosis. Future research is needed to better understand how these trajectories might shift over the course of the child's development. Results support the development of tailored, evidence-based interventions to address coping with uncertainty among families raising a child with chronic health needs.

Methods applied to neonatal dried blood spot samples for secondary research purposes: a scoping review

This scoping review aimed to synthesize the analytical techniques used and methodological limitations encountered when undertaking secondary research using residual neonatal dried blood spot (DBS) samples. Studies that used residual neonatal DBS samples for secondary research (i.e. research not related to newborn screening for inherited genetic and metabolic disorders) were identified from six electronic databases: Cochrane Library, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, Medline, PubMed and Scopus. Inclusion was restricted to studies published from 1973 and written in or translated into English that reported the storage, extraction and testing of neonatal DBS samples. Sixty-seven studies were eligible for inclusion. Included studies were predominantly methodological in nature and measured various analytes, including nucleic acids, proteins, metabolites, environmental pollutants, markers of prenatal substance use and medications. Neonatal DBS samples were stored over a range of temperatures (ambient temperature, cold storage or frozen) and durations (two weeks to 40.5 years), both of which impacted the recovery of some analytes, particularly amino acids, antibodies and environmental pollutants. The size of DBS sample used and potential contamination were also cited as methodological limitations. Residual neonatal DBS samples retained by newborn screening programs are a promising resource for secondary research purposes, with many studies reporting the successful measurement of analytes even from neonatal DBS samples stored for long periods of time in suboptimal temperatures and conditions.

Pain in Neonates: Perceptions and Current Practices

All newborns experience pain during routine care, which can have long-lasting negative effects. Despite the availability of effective methods to prevent and reduce pain, most infants will receive ineffective or no treatment. Optimal pain management includes the reduction of the number of procedures performed, routine pain assessment and the use of effective pain-reducing interventions, most notably breastfeeding, skin-to-skin contact and sweet-tasting solutions. Parents are an essential component of the comprehensive assessment and management of infant pain; however, a gap exists regarding the uptake of parent-led interventions and the engagement of families. Practice recommendations for infant pain care are discussed.

Prevalence of neonatal screening and associated factors in Brazil: a comparison of the 2013 and 2019 National Health Surveys

This study analyzed the prevalence of complete neonatal screening (CNS) of children aged under 2 years in Brazil and associated factors using data from the 2013 (n=4,442) and 2019 (n=5,643) national health surveys. We conducted a cross-sectional study to compare prevalence of CNS (eye, ear and heel prick tests) adopting 95% confidence intervals (95%CI) and a 5% significance level. Crude and adjusted Poisson regression was performed to estimate prevalence ratios (PR) and 95%CI to assess the association between socioeconomic, demographic and health variables and CNS. There was a statistically significant increase in CNS prevalence, from 49.2% (95%CI: 47.1-51.3) in 2013 to 67.4% (95%CI: 65.5-69.3) in 2019. However, large disparities persist across states and between sociodemographic groups. In both years, CNS prevalence was lowest among brown and black children, those from families in the three lowest income quintiles, children without health insurance, those from families registered in the Family Health Strategy and children living in the North, cities outside the state capital/metropolitan regions and rural areas. Despite the increase in prevalence of CNS, deep individual and contextual inequalities persist, posing challenges for health policies.

Estimating Gestational Age and Prediction of Preterm Birth Using Metabolomics Biomarkers

Preterm birth (PTB) is a leading cause of morbidity and mortality in children aged under 5 years globally, especially in low-resource settings. It remains a challenge in many low-income and middle-income countries to accurately measure the true burden of PTB due to limited availability of accurate measures of gestational age (GA), first trimester ultrasound dating being the gold standard. Metabolomics biomarkers are a promising area of research that could provide tools for both early identification of high-risk pregnancies and for the estimation of GA and preterm status of newborns postnatally.

Inherited metabolic disorders in Cyprus

Selective screening for inherited metabolic disorders (IMD) began in Cyprus in 1990. Over the last thirty-three years 7388 patients were investigated for IMD and 200 diagnoses were made (diagnostic yield 2.7%). The existence of a single laboratory of Biochemical Genetics for the whole island facilitated the creation of a national registry for IMD. The minimal prevalence of IMD in Cyprus is 53.3 cases per 100,000 live births. The most common group are disorders of amino acid metabolism (41.0%), followed by disorders of carbohydrate metabolism (16.5%), disorders of complex molecule degradation (16.5%), mitochondrial disorders (10.5%) and disorders of vitamin and co-factor metabolism (5.5%). Hyperphenylalaninaemia is the most common IMD (14.0%) followed by galactosaemia (7.0%), glutaric aciduria type I (5.5%) and MSUD (4.0%). Some disorders were found to have a relatively high incidence in specific communities, for example Sandhoff disease among the Cypriot Maronites and GM1 gangliosidosis in one particular area of the island. Other disorders were found to have a relatively higher overall incidence, compared to other Caucasian populations, for example galactosaemia, glutaric aciduria type I and MSUD, while fatty acid oxidation defects, Gaucher disease and classic PKU were found to have a relatively lower incidence. Molecular characterization of selected disorders revealed many novel genetic variants, specific to the Cypriot population.

Genomic Newborn Screening for Pediatric Cancer Predisposition Syndromes: A Holistic Approach

As next-generation sequencing (NGS) has become more widely used, germline and rare genetic variations responsible for inherited illnesses, including cancer predisposition syndromes (CPSs) that account for up to 10% of childhood malignancies, have been found. The CPSs are a group of germline genetic disorders that have been identified as risk factors for pediatric cancer development. Excluding a few "classic" CPSs, there is no agreement regarding when and how to conduct germline genetic diagnostic studies in children with cancer due to the constant evolution of knowledge in NGS technologies. Various clinical screening tools have been suggested to aid in the identification of individuals who are at greater risk, using diverse strategies and with varied outcomes. We present here an overview of the primary clinical and molecular characteristics of various CPSs and summarize the existing clinical genomics data on the prevalence of CPSs in pediatric cancer patients. Additionally, we discuss several ethical issues, challenges, limitations, cost-effectiveness, and integration of genomic newborn screening for CPSs into a healthcare system. Furthermore, we assess the effectiveness of commonly utilized decision-support tools in identifying patients who may benefit from genetic counseling and/or direct genetic testing. This investigation highlights a tailored and systematic approach utilizing medical newborn screening tools such as the genome sequencing of high-risk newborns for CPSs, which could be a practical and cost-effective strategy in pediatric cancer care.

Personalized metabolic whole-body models for newborns and infants predict growth and biomarkers of inherited metabolic diseases

Comprehensive whole-body models (WBMs) accounting for organ-specific dynamics have been developed to simulate adult metabolism, but such models do not exist for infants. Here, we present a resource of 360 organ-resolved, sex-specific models of newborn and infant metabolism (infant-WBMs) spanning the first 180 days of life. These infant-WBMs were parameterized to represent the distinct metabolic characteristics of newborns and infants, including nutrition, energy requirements, and thermoregulation. We demonstrate that the predicted infant growth was consistent with the recommendation by the World Health Organization. We assessed the infant-WBMs' reliability and capabilities for personalization by simulating 10,000 newborns based on their blood metabolome and birth weight. Furthermore, the infant-WBMs accurately predicted changes in known biomarkers over time and metabolic responses to treatment strategies for inherited metabolic diseases. The infant-WBM resource holds promise for personalized medicine, as the infant-WBMs could be a first step to digital metabolic twins for newborn and infant metabolism.

Current Status of Newborn Bloodspot Screening Worldwide 2024: A Comprehensive Review of Recent Activities (2020-2023)

Newborn bloodspot screening (NBS) began in the early 1960s based on the work of Dr. Robert "Bob" Guthrie in Buffalo, NY, USA. His development of a screening test for phenylketonuria on blood absorbed onto a special filter paper and transported to a remote testing laboratory began it all. Expansion of NBS to large numbers of asymptomatic congenital conditions flourishes in many settings while it has not yet been realized in others. The need for NBS as an efficient and effective public health prevention strategy that contributes to lowered morbidity and mortality wherever it is sustained is well known in the medical field but not necessarily by political policy makers. Acknowledging the value of national NBS reports published in 2007, the authors collaborated to create a worldwide NBS update in 2015. In a continuing attempt to review the progress of NBS globally, and to move towards a more harmonized and equitable screening system, we have updated our 2015 report with information available at the beginning of 2024. Reports on sub-Saharan Africa and the Caribbean, missing in 2015, have been included. Tables popular in the previous report have been updated with an eye towards harmonized comparisons. To emphasize areas needing attention globally, we have used regional tables containing similar listings of conditions screened, numbers of screening laboratories, and time at which specimen collection is recommended. Discussions are limited to bloodspot screening.

Comparative analysis of inherited metabolic diseases in normal newborns and high-risk children: Insights from a 10-year study in Shanghai

BACKGROUND

Compare the differences between normal newborns and high-risk children with inherited metabolic diseases. The disease profile includes amino acidemias, fatty acid oxidation disorders, and organic acidemias.

METHODS

Data was collected on newborns and children from high-risk populations in Shanghai from December 2010 to December 2020.

RESULTS

232,561 newborns were screened for disorders of organic, amino acid, and fatty acid metabolism. The initial positive rate was 0.66 % (1,526/232,561) and the positive recall rate was 77.85 %. The positive predictive value is 4.71 %. Among them, 56 cases were diagnosed as metabolic abnormalities. The total incidence rate is 1:4153. Hyperphenylalaninemia and short-chain acyl-CoA dehydrogenase are the most common diseases in newborns. In addition, in 56 children, 39 (69.42 %) were diagnosed by genetic sequencing. Some hotspot mutations in 14 IEMs have been observed, including PAH gene c.728G > A, c.611A > G, and ACADS gene c. 1031A > G, c.164C > T. A total of 49,860 symptomatic patients were screened, of which 185 were diagnosed with IEM, with a detection rate of 0.37 %. The most commonly diagnosed diseases in high-risk infants aremethylmalonic acidemia and hyperphenylalaninemia.

CONCLUSION

There are more clinical cases of congenital metabolic errors diagnosed by tandem mass spectrometry than newborn screening. The spectrum of diseases, prevalence, and genetic characteristics of normal newborns and high-risk children are quite different.

206,977 newborn screening results reveal the ethnic differences in the spectrum of inborn errors of metabolism in Huaihua, China

Background

Inborn errors of metabolism (IEMs) are rare diseases caused by inherited defects in various biochemical pathways that strongly correlate with early neonatal mortality and stunting. Currently, no studies have reported on the incidence of IEMs of multi-ethnic groups in Huaihua, China.

Methods

A total of 206,977 neonates with self-reported ethnicity who underwent IEM screening at Huaihua from 2015 to 2021 were selected for observation. Among them, 69 suspected IEM-positive neonates were referred for urine gas chromatography-mass spectrometry analysis, biochemical detection, next-generation sequencing, and Sanger sequencing.

Results

Sixty-nine newborns were diagnosed with IEMs, with an overall incidence of 1:3,000. The two most common disorders were 2-methylbutyryl glycinuria (1:7,137) and phenylalanine hydroxylase deficiency (1:22,997). Moreover, the incidence of IEMs in the minority ethnic group (Miao, Dong, Tujia and Yao) (1:1,852) was markedly higher than in the Han ethnic group (1:4,741). Some ethnic features variants were identified; NM_001609.4:c.1165A>G in the ACADSB gene for Miao and Dong ethnic groups, NM_014251.2:c.852_855del in the SLC25A13 gene for Miao ethnic groups.

Conclusion

This study revealed the IEM incidence within the minority ethnic groups is markedly higher than among the Han nationality and the gene variant spectrum is dramatically different in Huaihua, China. Hence, It serves as a theoretical reference for the screening and diagnosing of neonatal IEMs of multi-ethnic groups in the Huaihua area, and across China.

Genetic Screening-Emerging Issues

In many countries, some form of genetic screening is offered to all or part of the population, either in the form of well-organized screening programs or in a less formalized way. Screening can be offered at different phases of life, such as preconception, prenatal, neonatal and later in life. Screening should only be offered if the advantages outweigh the disadvantages. Technical innovations in testing and treatment are driving changes in the field of prenatal and neonatal screening, where many jurisdictions have organized population-based screening programs. As a result, a greater number and wider range of conditions are being added to the programs, which can benefit couples' reproductive autonomy (preconception and prenatal screening) and improve early diagnosis to prevent irreversible health damage in children (neonatal screening) and in adults (cancer and cascade screening). While many developments in screening are technology-driven, citizens may also express a demand for innovation in screening, as was the case with non-invasive prenatal testing. Relatively new emerging issues for genetic screening, especially if testing is performed using DNA sequencing, relate to organization, data storage and interpretation, benefit-harm ratio and distributive justice, information provision and follow-up, all connected to acceptability in current healthcare systems.

The newborn screening tests in Brazil: regional and socioeconomic prevalence and inequalities in 2013 and 2019

OBJECTIVE

To analyze the prevalence evolution of Guthrie, hearing, and eye screening testing among newborns in Brazil, between 2013 and 2019, according to demographic and socioeconomic characteristics.

METHODS

This is a cross-sectional study with data from 5231 infants from the Pesquisa Nacional de Saúde (PNS), in 2013, and 6637 infants, in 2019, for the Guthrie test, hearing, and red reflex tests. The authors analyzed the outcomes according to the region of residence, self-reported color/race, having health insurance, and per capita household income. By using bivariate and multivariate Poisson regression models, the prevalence ratios and their respective 95 % Confidence Intervals (CI95%) were calculated for each year.

RESULTS

In 2013, Guthrie test, hearing, and red reflex tests were performed in 96.5 % (95%CI 95,8;97,0), 65.8 % (95%CI 63,9;67,7), and 60.4 % (95%CI 58,5;62,3) of infants, respectively. In 2019, the prevalence was 97.8 % (95%CI 97,3;98,2) in the Guthrie test, 81.6 % (95%CI 80,3;82,9) in the hearing test, and 78.6 % (95%CI 77,1;79,9) in the red reflex test. The testing frequency was higher among residents of the Southeast and South regions of Brazil, among infants whose mother or guardian was white, had health insurance, and was in the higher income strata; and the most evident differences were in the eye and hearing testing.

CONCLUSIONS

The coverage inequalities according to the region of residence, income, and having health insurance highlight the need to use strategies that enable exams to be carried out, with more information about their importance, encompassing actions from primary care, prenatal care to the puerperium, aiming at universal access and equity.

Prevalence of Glucose-6-Phosphate Dehydrogenase Deficiency in Newborns in Northeast Mexico

OBJECTIVE

 Glucose-6-phosphate dehydrogenase deficiency (G6PDd) is the most common enzymatic disease worldwide and the prevalence is not well established because of the lack of screening. This study aimed to estimate the prevalence of G6PDd in a Hispanic population from Northeast Mexico.

STUDY DESIGN

 In this retrospective study, a database was used to analyze the G6PDd in neonates included in the expanded newborn metabolic screening of inherited metabolic disorders during a period of 4 years through the GSP Neonatal G6 kit (PerkinElmer).

RESULTS

 Among 96,152 (48,462 male) neonates screened for G6PD enzyme activity, a total of 566 (0.58%) cases were deficient for G6PD. Of those 566 patients, 469 (82.8%) attended the second test and the other 97 (17.2%) patients were lost. Of those 469 who did attend, 384 (81.9%) neonates were deficient in the second test and 85 (18.1%) were normal. With the data collected, 384 neonates were confirmed with G6PDd, 348 (88.6%) were male and 36 (11.4%) patients were female. The calculated prevalence for this population was 0.72 cases per 100 male newborns.

CONCLUSION

 The prevalence of G6PDd in the Northeastern Mexican population is high. Since migration is increasing in the United States, pediatricians should be aware of the need to search for G6PDd in newborns and the wide clinical manifestations they can present.

KEY POINTS

· The calculated prevalence of glucose-6-phosphate dehydrogenase deficiency in Northeast Mexico is 3.99 cases per 1,000 newborns.. · Glucose-6-phosphate dehydrogenase deficiency screenings should be included in all newborn metabolic screenings.. · Glucose-6-phosphate dehydrogenase deficiency is a common erythroenzymopathy that must be addressed as a public health concern. To anticipate clinical complications, target population monitoring is required..

Prospective cohort study of genomic newborn screening: BabyScreen+ pilot study protocol

INTRODUCTION

Newborn bloodspot screening (NBS) is a highly successful public health programme that uses biochemical and other assays to screen for severe but treatable childhood-onset conditions. Introducing genomic sequencing into NBS programmes increases the range of detectable conditions but raises practical and ethical issues. Evidence from prospectively ascertained cohorts is required to guide policy and future implementation. This study aims to develop, implement and evaluate a genomic NBS (gNBS) pilot programme.

METHODS AND ANALYSIS

The BabyScreen+ study will pilot gNBS in three phases. In the preimplementation phase, study materials, including education resources, decision support and data collection tools, will be designed. Focus groups and key informant interviews will also be undertaken to inform delivery of the study and future gNBS programmes. During the implementation phase, we will prospectively recruit birth parents in Victoria, Australia, to screen 1000 newborns for over 600 severe, treatable, childhood-onset conditions. Clinically accredited whole genome sequencing will be performed following standard NBS using the same sample. High chance results will be returned by genetic healthcare professionals, with follow-on genetic and other confirmatory testing and referral to specialist services as required. The postimplementation phase will evaluate the feasibility of gNBS as the primary aim, and assess ethical, implementation, psychosocial and health economic factors to inform future service delivery.

ETHICS AND DISSEMINATION

This project received ethics approval from the Royal Children's Hospital Melbourne Research Ethics Committee: HREC/91500/RCHM-2023, HREC/90929/RCHM-2022 and HREC/91392/RCHM-2022. Findings will be disseminated to policy-makers, and through peer-reviewed journals and conferences.

Neurological outcome in long-chain hydroxy fatty acid oxidation disorders

OBJECTIVE

This study aims to elucidate the long-term benefit of newborn screening (NBS) for individuals with long-chain 3-hydroxy-acyl-CoA dehydrogenase (LCHAD) and mitochondrial trifunctional protein (MTP) deficiency, inherited metabolic diseases included in NBS programs worldwide.

METHODS

German national multicenter study of individuals with confirmed LCHAD/MTP deficiency identified by NBS between 1999 and 2020 or selective metabolic screening. Analyses focused on NBS results, confirmatory diagnostics, and long-term clinical outcomes.

RESULTS

Sixty-seven individuals with LCHAD/MTP deficiency were included in the study, thereof 54 identified by NBS. All screened individuals with LCHAD deficiency survived, but four with MTP deficiency (14.8%) died during the study period. Despite NBS and early treatment neonatal decompensations (28%), symptomatic disease course (94%), later metabolic decompensations (80%), cardiomyopathy (28%), myopathy (82%), hepatopathy (32%), retinopathy (17%), and/or neuropathy (22%) occurred. Hospitalization rates were high (up to a mean of 2.4 times/year). Disease courses in screened individuals with LCHAD and MTP deficiency were similar except for neuropathy, occurring earlier in individuals with MTP deficiency (median 3.9 vs. 11.4 years; p = 0.0447). Achievement of dietary goals decreased with age, from 75% in the first year of life to 12% at age 10, and consensus group recommendations on dietary management were often not achieved.

INTERPRETATION

While NBS and early treatment result in improved (neonatal) survival, they cannot reliably prevent long-term morbidity in screened individuals with LCHAD/MTP deficiency, highlighting the urgent need of better therapeutic strategies and the development of disease course-altering treatment.

Fast Label-Free Metabolic Profile Recognition Identifies Phenylketonuria and Subtypes

Phenylketonuria (PKU) is the most common inherited metabolic disease in humans. Clinical screening of newborn heel blood samples for PKU is costly and time-consuming because it requires multiple procedures, like isotope labeling and derivatization, and PKU subtype identification requires an additional urine sample. Delayed diagnosis of PKU, or subtype identification can result in mental disability. Here, plasmonic silver nanoshells are used for laser desorption/ionization mass spectrometry (MS) detection of PKU with label-free assay by recognizing metabolic profile in dried blood spot (DBS) samples. A total of 1100 subjects are recruited and each DBS sample can be processed in seconds. This platform achieves PKU screening with a sensitivity of 0.985 and specificity of 0.995, which is comparable to existing clinical liquid chromatography MS (LC-MS) methods. This method can process 360 samples per hour, compared with the LC-MS method which processes only 30 samples per hour. Moreover, this assay enables precise identification of PKU subtypes without the need for a urine sample. It is demonstrated that this platform enables high-performance and fast, low-cost PKU screening and subtype identification. This approach might be suitable for the detection of other clinically relevant biomarkers in blood or other clinical samples.

Next-generation sequencing based newborn screening and comparative analysis with MS/MS

BACKGROUND

Newborn screening (NBS), such as tandem mass spectrometry (MS/MS), may yield false positive/negative results. Next-generation sequencing (NGS) has the potential to provide increased data output, efficiencies, and applications. This study aimed to analyze the types and distribution of pathogenic gene mutations in newborns in Huzhou, Zhejiang province, China and explore the applicability of NGS and MS/MS in NBS.

METHODS

Blood spot samples from 1263 newborns were collected. NGS was employed to screen for pathogenic variants in 542 disease-causing genes, and detected variants were validated using Sanger sequencing. Simultaneously, 26 inherited metabolic diseases (IMD) were screened using MS/MS. Positive or suspicious samples identified through MS/MS were cross-referenced with the results of NGS.

RESULTS

Among all newborns, 328 had no gene mutations detected. NGS revealed at least one gene mutation in 935 newborns, with a mutation rate of 74.0%. The top 5 genes were FLG, GJB2, UGT1A1, USH2A, and DUOX2. According to American College of Medical Genetics guidelines, gene mutations in 260 cases were classified as pathogenic or likely pathogenic mutation, with a positive rate of 20.6%. The top 5 genes were UGT1A1, FLG, GJB2, MEFV, and G6PD. MS/MS identified 18 positive or suspicious samples for IMD and 1245 negative samples. Verification of these cases by NGS results showed no pathogenic mutations, resulting in a false positive rate of 1.4% (18/1263).

CONCLUSION

NBS using NGS technology broadened the range of diseases screened, and enhanced the accuracy of diagnoses in comparison to MS/MS for screening IMD. Combining NGS and biochemical screening would improve the efficiency of current NBS.

A Systematic Literature Review on the Use of Dried Biofluid Microsampling in Patients With Kidney Disease

BACKGROUND

Kidney disease is fairly unique due to the lack of symptoms associated with disease activity, and it is therefore dependent on biological monitoring. Dried biofluids, particularly dried capillary blood spots, are an accessible, easy-to-use technology that have seen increased utility in basic science research over the past decade. However, their use is yet to reach the kidney patient population clinically or in large-scale discovery science initiatives. The aim of this study was to systematically evaluate the existing literature surrounding the use of dried biofluids in kidney research.

METHODS

A systematic literature review was conducted using three search engines and a predefined search term strategy. Results were summarised according to the collection method, type of biofluid, application to kidney disease, cost, sample stability and patient acceptability.

RESULTS

In total, 404 studies were identified and 67 were eligible. In total, 34,739 patients were recruited to these studies with a skew towards male participants (> 73%). The majority of samples were blood, which was used either for monitoring anti-rejection immunosuppressive drug concentrations or for kidney function. Dried biofluids offered significant cost savings to the patient and healthcare service. The majority of patients preferred home microsampling when compared to conventional monitoring.

CONCLUSION

There is an unmet need in bringing dried microsampling technology to advance kidney disease despite its advantages. This technology provides an opportunity to upscale patient recruitment and longitudinal sampling, enhance vein preservation and overcome participation bias in research.

Newborn screening in Colombia: The experience of a private program in Bogotá

Introduction. The first neonatal screening program in Colombia – PREGEN – was set up in the medical private sector of Bogotá in 1988. We report the results from recent years that, given the scarcity of similar information in our country, may help estimate the frequency of the evaluated neonatal disorders and which ones should be included in the neonatal screening programs in our country. Objective. To describe the results of PREGEN´s newborn screening program between 2006 and 2019. Materials and methods. We analyzed databases and other informative documents preserved in PREGEN from the 2006-2019 period. Results. One in every 164 newborns screened in our program had an abnormal hemoglobin variant, and one in every 194 carried some hemoglobin S variant. Glucose-6- phosphate dehydrogenase deficiency and congenital hypothyroidism are next as the more common disorders. Conclusions. Abnormal hemoglobin causes the most frequent monogenic disorder in the world. Glucose-6-phosphate dehydrogenase deficiency is the most common enzymopathy affecting nearly 400 million individuals worldwide. Since both disorders are more common in people of African descent and confer some resistance to malaria, we believe that screening for both disorders may be more relevant in the areas with African ancestry in our country.

Splice-Modulating Antisense Oligonucleotides as Therapeutics for Inherited Metabolic Diseases

The last decade (2013-2023) has seen unprecedented successes in the clinical translation of therapeutic antisense oligonucleotides (ASOs). Eight such molecules have been granted marketing approval by the United States Food and Drug Administration (US FDA) during the decade, after the first ASO drug, fomivirsen, was approved much earlier, in 1998. Splice-modulating ASOs have also been developed for the therapy of inborn errors of metabolism (IEMs), due to their ability to redirect aberrant splicing caused by mutations, thus recovering the expression of normal transcripts, and correcting the deficiency of functional proteins. The feasibility of treating IEM patients with splice-switching ASOs has been supported by FDA permission (2018) of the first "N-of-1" study of milasen, an investigational ASO drug for Batten disease. Although for IEM, owing to the rarity of individual disease and/or pathogenic mutation, only a low number of patients may be treated by ASOs that specifically suppress the aberrant splicing pattern of mutant precursor mRNA (pre-mRNA), splice-switching ASOs represent superior individualized molecular therapeutics for IEM. In this work, we first summarize the ASO technology with respect to its mechanisms of action, chemical modifications of nucleotides, and rational design of modified oligonucleotides; following that, we precisely provide a review of the current understanding of developing splice-modulating ASO-based therapeutics for IEM. In the concluding section, we suggest potential ways to improve and/or optimize the development of ASOs targeting IEM.

Evaluating a Novel Newborn Screening Methodology: Combined Genetic and Biochemical Screenings

PURPOSE

Analysis of four newborn screening modes using newborn genomic sequencing (nGS) and traditional biochemical screening (TBS).

METHODS

Prospective clinical study with a total of 1,012 newborn samples from retrospective TBS. Three independent groups performed the study under strict double-blind conditions according to the screening modes: independent biochemical (IBS), independent NeoSeq (INS), sequential (SS), and combined (CS) screening. Using targeted sequencing, the NeoSeq panel included 154 pathogenic genes covering 86 diseases.

RESULTS

Of the 1,012 newborns, 120 were diagnosed were diagnosed with genetic diseases Among them, 52 cases were within the scope of TBS and 68 additional cases were identified through nGS. The number of cases detected per screening mode was 50, 113, 56, and 119 for IBS, INS, SS, and CS, respectively. CS was the most satisfactory screening mode, with the detection rate of 99.17%, the specificity and positive predictive value of 100%, and the negative predictive value of 99.89%. In addition, of the 68 cases identified by nGS (96 variants in 31 pathogenic genes), only four participants (5.9%) had clinical manifestations consistent with the disease. The experimental reporting cycles of CS and INS were the shortest.

CONCLUSIONS

CS was the most satisfactory method for newborn screening, which combined nGS with TBS to improve early diagnosis.

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.

Analysis of Metabolic Changes in Endogenous Metabolites and Diagnostic Biomarkers for Various Diseases Using Liquid Chromatography and Mass Spectrometry

Analysis of endogenous metabolites in various diseases is useful for searching diagnostic biomarkers and elucidating the molecular mechanisms of pathophysiology. The author and collaborators have developed some LC/tandem mass spectrometry (LC/MS/MS) methods for metabolites and applied them to disease-related samples. First, we identified urinary conjugated cholesterol metabolites and serum N-palmitoyl-O-phosphocholine serine as useful biomarkers for Niemann-Pick disease type C (NPC). For the purpose of intraoperative diagnosis of glioma patients, we developed the LC/MS/MS analysis methods for 2-hydroxyglutaric acid or cystine and found that they could be good differential biomarkers. For renal cell carcinoma, we searched for various biomarkers for early diagnosis, malignancy evaluation and recurrence prediction by global metabolome analysis and targeted LC/MS/MS analysis. In pathological analysis, we developed a simultaneous LC/MS/MS analysis method for 13 steroid hormones and applied it to NPC cells, we found 6 types of reductions in NPC model cells. For non-alcoholic steatohepatitis (NASH), model mice were prepared with special diet and plasma bile acids were measured, and as a result, hydrophilic bile acids were significantly increased. In addition, we developed an LC/MS/MS method for 17 sterols and analyzed liver cholesterol metabolites and found a decrease in phytosterols and cholesterol synthetic markers and an increase in non-enzymatic oxidative sterols in the pre-onset stage of NASH. We will continue to challenge themselves to add value to clinical practice based on cutting-edge analytical chemistry methodology.

Incidental Detection of Classical Galactosemia through Newborn Screening for Phenylketonuria: A 10-Year Retrospective Audit to Determine the Efficacy of This Approach

In the UK, Classical Galactosaemia (CG) is identified incidentally from the Newborn Screening (NBS) for phenylketonuria (PKU) using an "Other disorder suspected" (ODS) pathway when phenylalanine (Phe) and tyrosine (Tyr) concentrations are increased. We aimed to determine the efficacy of CG detection via NBS and estimate the incidence of CG in live births in the UK. A survey was sent to all UK NBS laboratories to collate CG cases diagnosed in the UK from 2010 to 2020. Cases of CG diagnosed were determined if detected clinically, NBS, or by family screening, as well as age at diagnosis. Cases referred via the ODS pathway were also collated, including the final diagnosis made. Responses were obtained from 13/16 laboratories. Between 2010 and 2020, a total of 6,642,787 babies were screened, and 172 cases of CG were identified. It should be noted that 85/172 presented clinically, 52/172 were identified by NBS, and 17/172 came from family screening. A total of 117 referrals were made via the ODS pathway, and 45/117 were subsequently diagnosed with CG. Median (interquartile range) age at diagnosis by NBS and clinically was 8 days (7-11) and 10 days (7-16), respectively (Mann-Whitney U test, U = 836.5, p-value = 0.082). The incidence of CG is 1:38,621 live births. The incidence of CG in the UK is comparable with that of other European/western countries. No statistical difference was seen in the timing of diagnosis between NBS and clinical presentation based on the current practice of sampling on day 5. Bringing forward the day of NBS sampling to day 3 would increase the proportion diagnosed with CG by NBS from 52/172 (30.2%) to 66/172 (38.4%).

Compilation of Genotype and Phenotype Data in GCDH-LOVD for Variant Classification and Further Application

Glutaric aciduria type 1 (GA-1) is a rare but treatable autosomal-recessive neurometabolic disorder of lysin metabolism caused by biallelic pathogenic variants in glutaryl-CoA dehydrogenase gene (GCDH) that lead to deficiency of GCDH protein. Without treatment, this enzyme defect causes a neurological phenotype characterized by movement disorder and cognitive impairment. Based on a comprehensive literature search, we established a large dataset of GCDH variants using the Leiden Open Variation Database (LOVD) to summarize the known genotypes and the clinical and biochemical phenotypes associated with GA-1. With these data, we developed a GCDH-specific variation classification framework based on American College of Medical Genetics and Genomics and the Association for Molecular Pathology guidelines. We used this framework to reclassify published variants and to describe their geographic distribution, both of which have practical implications for the molecular genetic diagnosis of GA-1. The freely available GCDH-specific LOVD dataset provides a basis for diagnostic laboratories and researchers to further optimize their knowledge and molecular diagnosis of this rare disease.

A False-Negative Newborn Screen for Tyrosinemia Type 1-Need for Re-Evaluation of Newborn Screening with Succinylacetone

Undiagnosed and untreated tyrosinemia type 1 (TT1) individuals carry a significant risk for developing liver fibrosis, cirrhosis and hepatocellular carcinoma (HCC). Elevated succinylacetone (SA) is pathognomonic for TT1 and therefore often used as marker for TT1 newborn screening (NBS). While SA was long considered to be elevated in every TT1 patient, here we present a recent false-negative SA TT1 screen. A nine-year-old boy presented with HCC in a cirrhotic liver. Additional tests for the underlying cause unexpectedly revealed TT1. Nine years prior, the patient was screened for TT1 via SA NBS with a negative result: SA 1.08 µmol/L, NBS cut-off 1.20 µmol/L. To our knowledge, this report is the first to describe a false-negative result from the TT1 NBS using SA. False-negative TT1 NBS results may be caused by milder TT1 variants with lower SA excretion. Such patients are more likely to be missed in NBS programs and can be asymptomatic for years. Based on our case, we advise TT1 to be considered in patients with otherwise unexplained liver pathology, including fibrosis, cirrhosis and HCC, despite a previous negative TT1 NBS status. Moreover, because the NBS SA concentration of this patient fell below the Dutch cut-off value (1.20 µmol/L at that time), as well as below the range of cut-off values used in other countries (1.29-10 µmol/L), it is likely that false-negative screening results for TT1 may also be occurring internationally. This underscores the need to re-evaluate TT1 SA NBS programs.

Androgen Excess and Deficiency: Analytical and Diagnostic Approaches

BACKGROUND

Androgens are synthesized from cholesterol through sequential conversions by enzymes in the adrenal glands and gonads. Serum levels of androgens change during the different phases of life and regulate important developmental and maturational processes. Androgen excess or deficiency can therefore present at various ages in various ways.

CONTENT

The diagnostic approach for atypical genitalia, premature pubarche, delayed pubertal onset or progression, and hirsutism or virilization, including measurement of androgens (testosterone, androstenedione, 17-OHprogesterone, dehydroepiandrosterone, and dihydrotestosterone) is discussed in the current review. Androgens can be measured in serum, saliva, urine, or dried blood spots. Techniques to measure androgens, including immunoassays and LC-MS, have their own advantages and pitfalls. In addition, pre- and postanalytical issues are important when measuring androgens.

SUMMARY

During clinical interpretation of androgen measurements, it is important to take preanalytical circumstances, such as time of blood withdrawal, into account. As immunoassays have major drawbacks, especially in samples from women and neonates, concentrations measured using these assays should be interpreted with care. Reference intervals can only be used in relation to the measurement technique and the standardization of the assay. In the near future, new androgens will probably be added to the current repertoire to further improve the diagnosis and follow-up of androgen excess or deficiency.

Identification of maternal attitudes and knowledge about newborn screenings: a Turkey sample

This study was planned to determine maternal attitudes and knowledge about newborn screening. The universe of the descriptive study consisted of postpartum mothers living in the centers of three provinces in the north and east of Turkey. The sample included mothers who were older than 18 years of age, who could read and write Turkish, whose babies were in the 24th and 72nd hour after birth, and who volunteered to take part in the study. The study was completed with 407 mothers. The data were collected with the face-to-face interview method by the researchers using the "Descriptive Information Form" and the "Maternal Attitudes and Knowledge Survey about Newborn Screening." The results showed that 40.3% of the mothers were between the ages of 25 and 30 years, 52.8% received information about newborn screening, 61.1% received this information during pregnancy (27.3% in the first trimester and 33.8% in the last trimester), and most of the information was provided by a healthcare professional (77.8%). Mothers with only one child (p = .001) and those with nuclear families (p = .024) were found to have lower maternal attitudes and knowledge about newborn screening. The study showed that the level of knowledge of Turkish mothers about newborn screening is inadequate in general. In particular, the knowledge and attitudes of mothers with nuclear families, those with one child, and those not having regular check-ups during pregnancy are inadequate. Improving mothers' understanding of screening tests will lead to more successful screening program implementation and earlier detection and care of newborns with a disease.

Landscape of Adrenal Tumours in Patients with Congenital Adrenal Hyperplasia

Our aim is to update the topic of adrenal tumours (ATs) in congenital adrenal hyperplasia (CAH) based on a multidisciplinary, clinical perspective via an endocrine approach. This narrative review is based on a PubMed search of full-length, English articles between January 2014 and July 2023. We included 52 original papers: 9 studies, 8 case series, and 35 single case reports. Firstly, we introduce a case-based analysis of 59 CAH-ATs cases with four types of enzymatic defects (CYP21A2, CYP17A1, CYP17B1, and HSD3B2). Secondarily, we analysed prevalence studies; their sample size varied from 53 to 26,000 individuals. AT prevalence among CAH was of 13.3-20%. CAH prevalence among individuals with previous imaging diagnosis of AT was of 0.3-3.6%. Overall, this 10-year, sample-based analysis represents one of the most complex studies in the area of CAH-ATs so far. These masses should be taken into consideration. They may reach impressive sizes of up to 30-40 cm, with compressive effects. Adrenalectomy was chosen based on an individual multidisciplinary decision. Many tumours are detected in subjects with a poor disease control, or they represent the first step toward CAH identification. We noted a left lateralization with a less clear pathogenic explanation. The most frequent tumour remains myelolipoma. The risk of adrenocortical carcinoma should not be overlooked. Noting the increasing prevalence of adrenal incidentalomas, CAH testing might be indicated to identify non-classical forms of CAH.

Precocious Puberty in Hypothyroidism: Mini-Review of Van Wyk-Grumbach Syndrome

Severe hypothyroidism can affect a variety of organs and can develop atypical manifestations. Peripheral precocious puberty may be secondary to other endocrinological diseases, which must be taken into account in the differential diagnosis in order to avoid unnecessary additional tests. Van Wyk-Grumbach syndrome is an infrequent manifestation characterized by severe hypothyroidism and incomplete precocious puberty. Diagnosis is made by clinical and complementary tests, and the main treatment goal is to achieve euthyroidism through hormone replacement. Prognosis is good once the treatment is established. The aim of this study is to review the available literature about Van Wyk-Grumbach syndrome following the PRISMA statement, and to present the first clinical case published in Spain. We have included the articles published during the period from 1905 to week 40 of 2022. A total of 68 articles have been selected for study and analysis, within which there are 99 published clinical cases. Girls accounted for 92.1% of cases (median age at the diagnosis 8.5 years). Metrorrhagia was the most prevalent symptom, present in 80.5% of the girls. Abdominal ultrasound was performed in 93.3% of the girls and 97.8% of them had at least one ovarian cyst. All cases were treated with levothyroxine, responding satisfactorily after the first doses of treatment. To conclude, Van Wyk-Grumbach syndrome is characterized by severe hypothyroidism and incomplete precocious puberty, which is important to keep in mind in order to avoid complementary exams and unnecessary surgical interventions.

[Evaluation and optimization of newborn screening by structured long-term follow-up-using the example of inherited metabolic diseases]

Newborn screening (NBS) is a highly successful secondary prevention program with the goal of preventing severe sequelae of congenital, mostly genetic, diseases by identifying them as early as possible, ideally in the pre-symptomatic period. Studies to date have shown the important achievements of NBS programs but also reveal a number of relevant weaknesses. These include the often incompletely understood natural history and phenotypic diversity of rare diseases as well as the inadequate ability to accurately predict individual disease severity at an early stage and thus the uncertainties in case definition, risk stratification, and treatment indication.In light of the rapid developments in high-throughput genetic technologies and the associated opportunities for substantial future expansion of NBS programs, it seems overdue to make structured long-term follow-up and the subsequent evaluation of the long-term health benefits mandatory for individuals with rare diseases identified through NBS. This article explains the importance of long-term follow-up for the evaluation and continuous optimization of the screening. Long-term clinical outcomes of people with inherited metabolic diseases identified by NBS are presented as examples.

[Newborn blood spot screening (NBS) in Germany : Status quo and presentation of a concept for further development]

Newborn screening from dried blood spots (NBS) is a highly effective secondary prevention measure that has been established for many years. Against the background of the inclusion of "new diseases" that meet the screening criteria, a concept for the further advancement of NBS was developed on behalf of the GKV-Spitzenverband. This was based on a systematic literature review and a survey of the status quo of NBS in Germany using quantitative and qualitative methods.It is essential for the success of NBS that all newborns affected by a target disease are diagnosed and treated at an early stage and that the harm to be expected with each screening (e.g., due to false positive findings) is kept as low as possible. This requires the organisation of screening in the sense of an integrated programme through central coordination with standardised structures, continuous quality management and digitalisation in line with data protection requirements.Although in general NBS is being implemented successfully in Germany, the research project presented here also reveals weaknesses and a need for action. Proposals and recommendations were compiled in a concept paper, which shows approaches for further development of NBS in line with the current state of research in consideration of changing demands on the infrastructure and processes in the health system. This review article summarises the challenges, current status and possible solutions for the central topics of the concept paper.

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.

[Genomic newborn screening-research approaches, challenges, and opportunities]

The application of high-throughput sequencing methods for population-based genomic newborn screening offers numerous opportunities for improving population health. The use of genome-based sequencing technology holds potential to enable the diagnosis of virtually any genetic disorder at an early stage and offers great flexibility when it comes to selection and expansion of target diseases. National and international efforts are therefore being made to investigate the ethical, legal, social, psychological, and technical aspects of genomic newborn screening. In addition to the many opportunities, there are numerous challenges and questions that remain to be answered: When and how should legal guardians be informed about such screening? Which diseases should be screened for? How should incidental findings or identification of a genetic predisposition be dealt with? Should data be stored long term and if so, how can this be done securely? Provided there is an appropriate regulatory framework and a transparent consent process, genomic newborn screening has the potential to fundamentally change the way in which we screen for congenital diseases. However, there is still much to be done. To achieve understanding and acceptance of genomic newborn screening amongst all stakeholders and thus to maximize its benefits for the population, a public discourse on the possibilities and limitations of genomic newborn screening is of critical importance. This article aims to provide an overview of the innovative technical developments in the field of human genetics, describe national and international approaches, and discuss challenges and opportunities of genomic newborn screening development.

Isovaleric aciduria identified by newborn screening: Strategies to predict disease severity and stratify treatment

Newborn screening (NBS) allows early identification of individuals with rare disease, such as isovaleric aciduria (IVA). Reliable early prediction of disease severity of positively screened individuals with IVA is needed to guide therapeutic decision, prevent life-threatening neonatal disease manifestation in classic IVA and over-medicalization in attenuated IVA that may remain asymptomatic. We analyzed 84 individuals (median age at last study visit 8.5 years) with confirmed IVA identified by NBS between 1998 and 2018 who participated in the national, observational, multicenter study. Screening results, additional metabolic parameters, genotypes, and clinical phenotypic data were included. Individuals with metabolic decompensation showed a higher median isovalerylcarnitine (C5) concentration in the first NBS sample (10.6 vs. 2.7 μmol/L; p < 0.0001) and initial urinary isovalerylglycine concentration (1750 vs. 180 mmol/mol creatinine; p = 0.0003) than those who remained asymptomatic. C5 was in trend inversely correlated with full IQ (R = -0.255; slope = -0.869; p = 0.0870) and was lower for the "attenuated" variants compared to classic genotypes [median (IQR; range): 2.6 μmol/L (2.1-4.0; 0.7-6.4) versus 10.3 μmol/L (7.4-13.1; 4.3-21.7); N = 73]. In-silico prediction scores (M-CAP, MetaSVM, and MetaLR) correlated highly with isovalerylglycine and ratios of C5 to free carnitine and acetylcarnitine, but not sufficiently with clinical endpoints. The results of the first NBS sample and biochemical confirmatory testing are reliable early predictors of the clinical course of IVA, facilitating case definition (attenuated versus classic IVA). Prediction of attenuated IVA is supported by the genotype. On this basis, a reasonable algorithm has been established for neonates with a positive NBS result for IVA, with the aim of providing the necessary treatment immediately, but whenever possible, adjusting the treatment to the individual severity of the disease.

Rare diseases' genetic newborn screening as the gateway to future genomic medicine: the Screen4Care EU-IMI project

Following the reverse genetics strategy developed in the 1980s to pioneer the identification of disease genes, genome(s) sequencing has opened the era of genomics medicine. The human genome project has led to an innumerable series of applications of omics sciences on global health, from which rare diseases (RDs) have greatly benefited. This has propelled the scientific community towards major breakthroughs in disease genes discovery, in technical innovations in bioinformatics, and in the development of patients' data registries and omics repositories where sequencing data are stored. Rare diseases were the first diseases where nucleic acid-based therapies have been applied. Gene therapy, molecular therapy using RNA constructs, and medicines modulating transcription or translation mechanisms have been developed for RD patients and started a new era of medical science breakthroughs. These achievements together with optimization of highly scalable next generation sequencing strategies now allow movement towards genetic newborn screening. Its applications in human health will be challenging, while expected to positively impact the RD diagnostic journey. Genetic newborn screening brings many complexities to be solved, technical, strategic, ethical, and legal, which the RD community is committed to address. Genetic newborn screening initiatives are therefore blossoming worldwide, and the EU-IMI framework has funded the project Screen4Care. This large Consortium will apply a dual genetic and digital strategy to design a comprehensive genetic newborn screening framework to be possibly translated into the future health care.

Functional and structural impact of 10 ACADM missense mutations on human medium chain acyl-Coa dehydrogenase

Medium chain acyl-CoA dehydrogenase (MCAD) deficiency (MCADD) is associated with ACADM gene mutations, leading to an impaired function and/or structure of MCAD. Importantly, after import into the mitochondria, MCAD must incorporate a molecule of flavin adenine dinucleotide (FAD) per subunit and assemble into tetramers. However, the effect of MCAD amino acid substitutions on FAD incorporation has not been investigated. Herein, the commonest MCAD variant (p.K304E) and 11 additional rare variants (p.Y48C, p.R55G, p.A88P, p.Y133C, p.A140T, p.D143V, p.G224R, p.L238F, p.V264I, p.Y372N, and p.G377V) were functionally and structurally characterized. Half of the studied variants presented a FAD content <65 % compared to the wild-type. Most of them were recovered as tetramers, except the p.Y372N (mainly as dimers). No correlation was found between the levels of tetramers and FAD content. However, a correlation between FAD content and the cofactor's affinity, proteolytic stability, thermostability, and thermal inactivation was established. We showed that the studied amino acid changes in MCAD may alter the substrate chain-length dependence and the interaction with electron-transferring-flavoprotein (ETF) necessary for a proper functioning electron transfer thus adding additional layers of complexity to the pathological effect of ACADM missense mutations. Although the majority of the variant MCADs presented an impaired capacity to retain FAD during their synthesis, some of them were structurally rescued by cofactor supplementation, suggesting that in the mitochondrial environment the levels and activity of those variants may be dependent of FAD's availability thus contributing for the heterogeneity of the MCADD phenotype found in patients presenting the same genotype.

Whole-Genome Sequencing Can Identify Clinically Relevant Variants from a Single Sub-Punch of a Dried Blood Spot Specimen

The collection of dried blood spots (DBS) facilitates newborn screening for a variety of rare, but very serious conditions in healthcare systems around the world. Sub-punches of varying sizes (1.5-6 mm) can be taken from DBS specimens to use as inputs for a range of biochemical assays. Advances in DNA sequencing workflows allow whole-genome sequencing (WGS) libraries to be generated directly from inputs such as peripheral blood, saliva, and DBS. We compared WGS metrics obtained from libraries generated directly from DBS to those generated from DNA extracted from peripheral blood, the standard input for this type of assay. We explored the flexibility of DBS as an input for WGS by altering the punch number and size as inputs to the assay. We showed that WGS libraries can be successfully generated from a variety of DBS inputs, including a single 3 mm or 6 mm diameter punch, with equivalent data quality observed across a number of key metrics of importance in the detection of gene variants. We observed no difference in the performance of DBS and peripheral-blood-extracted DNA in the detection of likely pathogenic gene variants in samples taken from individuals with cystic fibrosis or phenylketonuria. WGS can be performed directly from DBS and is a powerful method for the rapid discovery of clinically relevant, disease-causing gene variants.

Genomic Sequencing as a First-Tier Screening Test and Outcomes of Newborn Screening

Importance

Newborn screening via biochemical tests is in use worldwide. The availability of genetic sequencing has allowed rapid screening for a substantial number of monogenic disorders. However, the outcomes of this strategy have not been evaluated in a general newborn population.

Objective

To evaluate the outcomes of applying gene panel sequencing as a first-tier newborn screening test.

Design, Setting, and Participants

This cohort study included newborns who were prospectively recruited from 8 screening centers in China between February 21 and December 31, 2021. Neonates with positive results were followed up before July 5, 2022.

Exposures

All participants were concurrently screened using dried blood spots. The screen consisted of biochemical screening tests and a targeted gene panel sequencing test for 128 conditions. The biochemical and genomic tests could both detect 43 of the conditions, whereas the other 85 conditions were screened solely by the gene panel.

Main Outcomes and Measures

The primary outcomes were the number of patients detected by gene panel sequencing but undetected by the biochemical test.

Results

This study prospectively recruited 29 601 newborns (15 357 [51.2%] male). The mean (SD) gestational age was 39.0 (1.5) weeks, and the mean (SD) birth weight was 3273 (457) g. The gene panel sequencing screened 813 infants (2.7%; 95% CI, 2.6%-2.9%) as positive. By the date of follow-up, 402 infants (1.4%; 95% CI, 1.2%-1.5%) had been diagnosed, indicating the positive predictive value was 50.4% (95% CI, 50.0%-53.9%). The gene panel sequencing identified 59 patients undetected by biochemical tests, including 20 patients affected by biochemically and genetically screened disorders and 39 patients affected by solely genetically screened disorders, which translates into 1 out of every 500 newborns (95% CI, 1/385-1/625) benefiting from the implementation of gene panels as a first-tier screening test.

Conclusions and Relevance

In this cohort study, the use of gene panel sequencing in a general newborn population as a first-tier screening test improved the detection capability of traditional screening, providing an evidence-based suggestion that it could be considered as a crucial method for first-tier screening.

Genomic newborn screening: Are we entering a new era of screening?

Population newborn screening (NBS) for phenylketonuria began in the United States in 1963. In the 1990s electrospray ionization mass spectrometry permitted an array of pathognomonic metabolites to be identified simultaneously, enabling up to 60 disorders to be recognized with a single test. In response, differing approaches to the assessment of the harms and benefits of screening have resulted in variable screening panels worldwide. Thirty years on and another screening revolution has emerged with the potential for first line genomic testing extending the range of screening conditions recognized after birth to many hundreds. At the annual SSIEM conference in 2022 in Freiburg, Germany, an interactive plenary discussion on genomic screening strategies and their challenges and opportunities was conducted. The Genomics England Research project proposes the use of Whole Genome Sequencing to offer extended NBS to 100 000 babies for defined conditions with a clear benefit for the child. The European Organization for Rare Diseases seeks to include "actionable" conditions considering also other types of benefits. Hopkins Van Mil, a private UK research institute, determined the views of citizens and revealed as a precondition that families are provided with adequate information, qualified support, and that autonomy and data are protected. From an ethical standpoint, the benefits ascribed to screening and early treatment need to be considered in relation to asymptomatic, phenotypically mild or late-onset presentations, where presymptomatic treatment may not be required. The different perspectives and arguments demonstrate the unique burden of responsibility on those proposing new and far-reaching developments in NBS programs and the need to carefully consider both harms and benefits.

The Urinary Metabolomic Fingerprint in Extremely Preterm Infants on Total Parenteral Nutrition vs. Enteral Feeds

Total Parenteral Nutrition (TPN), which uses intravenous administration of nutrients, minerals and vitamins, is essential for sustaining premature infants until they transition to enteral feeds, but there is limited information on metabolomic differences between infants on TPN and enteral feeds. We performed untargeted global metabolomics on urine samples collected between 23-30 days of life from 314 infants born <29 weeks gestational age from the TOLSURF and PROP cohorts. Principal component analysis across all metabolites showed a separation of infants solely on TPN compared to infants who had transitioned to enteral feeds, indicating global metabolomic differences between infants based on feeding status. Among 913 metabolites that passed quality control filters, 609 varied in abundance between infants on TPN vs. enteral feeds at p < 0.05. Of these, 88% were in the direction of higher abundance in the urine of infants on enteral feeds. In a subset of infants in a longitudinal analysis, both concurrent and delayed changes in metabolite levels were observed with the initiation of enteral feeds. These infants had higher concentrations of essential amino acids, lipids, and vitamins, which are necessary for growth and development, suggesting the nutritional benefit of an enteral feeding regimen.

Development of a Model for Quantitative Assessment of Newborn Screening in Japan Using the Analytic Hierarchy Process

Whether or not conditions should be included in publicly funded newborn screening (NBS) programs should be discussed according to objective and transparent criteria. Certain criteria have been developed for the introduction of NBS programs in the context of individual countries; however, there are no standard selection criteria for NBS programs in Japan. This study aimed to develop a quantitative scoring model to assess newborn screening that incorporates the views of a variety of stakeholders in Japan. The five recommended eligibility criteria for NBS were stratified based on previous studies and expert opinions, using the analytic hierarchy process. We conducted a cross-sectional, web-based questionnaire targeting a wide range of people involved in NBS to investigate pairwise comparisons of the evaluation items between February and April of 2022. There were 143 respondents. Most of our respondents (44.1%) were physicians. Fifty-eight respondents (40.6%) had been engaged in NBS-related research or work for more than 10 years. The distribution of allocation points was the highest for 'intervention', 'screening test', 'follow-up setting', 'economic evaluation', and 'disease/condition', in that order. The algorithm in this study will guide decision makers in collecting and evaluating objective data, thus enabling transparent discussions to occur.

An Insight into Indonesia's Challenges in Implementing Newborn Screening Programs and Their Future Implications

Due to high entry barriers, countries might find it daunting to implement the NBS program, especially those just trying to start it. This review aims to discuss Indonesia's barriers that hinder newborn screening (NBS) implementation while discussing the future implications. Literature in Pubmed and Google Scholar was scoured with keywords such as "Newborn Screening", "Neonatal Screening", "Indonesia", "Asia Pacific", "Barriers", and "Challenges". We also searched for relevant references in those published articles. Grey literature, such as state regulations, informative webinars on the topics by experts regarding current situations, and press releases by the Indonesian Minister of Health (MoH), was also searched. Newborn screening is no longer considered just a laboratory test but an array of well-harmonized systems that must be orchestrated well. Some of the barriers Indonesia faces in implementing NBS are a lack of prevalence data, ethical issues, infrastructure, cost-benefit analysis, logistical issues, government support, patient issues, a lack of commitments, and a lack of healthcare workers, specialization, and training. Government support with professional advocates and support groups, proper infrastructure, and a single-payer system for NBS programs are necessary to accelerate NBS programs in Indonesia.

Inherited Metabolic Diseases from Past to Present: A Bibliometric Analysis (1968-2023)

Bibliometric studies on inherited metabolic diseases (IMDs) do not exist in the literature. Therefore, our research aims to conduct a bibliometric study to determine the current status, trending topics, and missing points of publications on IMDs. Between 1968 and 2023, we conducted a literature search with the keyword "inherited metabolic disease" in the SCOPUS database. We included research articles in medicine written in English and published in the final section. We created our data pool using VOSviewer, SciMAT, and Rstudio software programs for the bibliometric parameters of the articles that met the inclusion criteria. We performed a bibliometric analysis of the data with the R package "bibliometrix" and BibExcel programs. We included 2702 research articles published on IMDs. The top three countries that have written the most articles in this field are the USA (n = 501), the United Kingdom (n = 182), and China (n = 172). The most preferred keywords by the authors were: newborn screening (n = 54), mutation (n = 43), phenylketonuria (n = 42), children (n = 35), genetics (n = 34), and maple syrup urine disease (n = 32). Trending topics were osteoporosis, computed tomography, bone marrow transplantation in the early years of the study, chronic kidney disease, urea cycle disorders, next-generation sequencing, newborn screening, and familial hypercholesterolemia in the final years of the study. This study provides clinicians with a new perspective, showing that molecular and genetic studies of inherited metabolic diseases will play an essential role in diagnosis and treatment in the future.