PURPOSE: Hereditary vascular disorders are clinically and genetically heterogeneous, predisposing patients to aneurysms, dissections, or vascular tumours. Despite advances in molecular diagnostics, integration of genetic testing into routine care remains an unmet need and a challenge of high clinical relevance. METHODS: Implementation of an interdisciplinary outpatient clinic for vascular genetics evaluations. Patient selection based on current clinical recommendations for genetic diagnostics and counselling for vascular aneurysms/ dissections and carotid paraganglioma (CPGL). Single‑center, retrospective descriptive analysis of systematically recorded clinical and genetic data of all patients attending the Heidelberg specialized vascular-genetic outpatient clinic between 2021 and 2025. RESULTS: We present five-year experience from a systematic and interdisciplinary clinical pathway for patients with aortopathies or carotid paraganglioma (CPGL), including pre‑visit data capture, interdisciplinary phenotyping, integrated pre‑ and post‑test counselling, and molecular guided clinical management. Pathological genetic findings in our aortic aneurysm/dissection and CPGL cohort were 16% (10/63) and 29% (10/34), respectively. The presence of multiple clinical predictors, defined as key risk indicators including early age at onset, multifocal disease, and positive family history, did not significantly influence the ratio of pathologic genetic findings in the aneurysm cohort, whereas a higher number of predictors was associated with increased number of pathogenic genetic variants in the CPGL cohort. CONCLUSION: A dedicated, interdisciplinary vascular genetics clinic can be feasibly implemented within routine clinical care. The proposed structured workflow provides a blueprint to systematically integrate genetics into vascular surgery and related clinical disciplines.

PURPOSE: This study assessed general attitudes toward genomic newborn screening (gNBS) among the German public. METHODS: In a population-representative survey, we assessed self-rated prior knowledge of gNBS, newborn screening (NBS), and genome sequencing and perceived attitudinal and informational uncertainty and agreement with potential advantages and disadvantages of gNBS via paper-based questionnaire. Sociodemographic information was obtained through interviews. Analyses included descriptive statistics and multiple linear regressions. RESULTS: Respondents (N = 2504; ages 16-92) rated their prior knowledge as low, especially for gNBS compared with NBS. Informational uncertainty was higher among individuals with lower self-rated prior knowledge, lower educational attainment, and lower income, whereas attitudinal uncertainty showed no significant correlates with sociodemographic factors. Agreement with potential advantages of gNBS outweighed that of potential disadvantages. Higher self-rated prior knowledge and income predicted higher agreement with advantages. Right-leaning political views correlated with greater agreement with disadvantages. Overall, sociodemographic factors explained little variance. CONCLUSION: Perceptions of gNBS were predominantly positive, although marked by uncertainty and low prior knowledge. Although some sociodemographic differences emerged, their influence on attitudes was limited. Additional factors, such as personality traits, may help explain attitude differences. Given low prior knowledge and its association with support for gNBS, improving genetic literacy through diverse outreach strategies is essential to enhance public acceptance of gNBS in Germany.

Transaldolase deficiency is a rare metabolic disease caused by pathogenic variants in the TALDO1 gene. Transaldolase plays an important role in the ribose-5-phosphate production, maintaining the NADPH-dependent lipid biosynthesis and cellular redox homeostasis. A small number of patients, predominantly children, have been reported, with a wide range of phenotypic presentations, including liver and kidney disease, involvement of the hematopoietic and endocrine systems, as well as possible early death. We aim to provide further insight into the clinical progression of transaldolase deficiency in adolescence and adulthood. We report on three adult patients with genetically confirmed transaldolase deficiency, including two novel genetic variants in TALDO1. Although the patients have been symptomatic since newborn age, initially with hepatomegaly and cytopenias, they were only diagnosed during adolescence or adulthood. Genetic analysis was performed only at 17, 26, and 32 years, respectively, which, however, did not reveal any genetic variants that would be expected to cause a milder disease course. In adulthood, the dominant clinical features were hypergonadotropic hypogonadism, osteopenia, renal and hepatic involvement. In conclusion, when reporting three new adult cases and comparing them with 47 accessible cases from the literature, our findings suggest that, even if clinical manifestations begin in the neonatal period, the overall phenotype may remain relatively mild, with gradual progression. This means that patients presenting with otherwise unexplained progressive liver disease, kidney dysfunction, cytopenia, and hypergonadotropic hypogonadism should be tested for transaldolase deficiency. We recommend closely monitoring patients with known transaldolase deficiency regarding the above-mentioned problems.

Newborn screening (NBS) is an effective measure of secondary prevention. The application of genomic sequencing in population-based screening would enable further expansions of the NBS disease panel and a genomic NBS (gNBS). The selection of NBS target diseases is still based on the Wilson and Jungner screening principles from 1968, which are considered incomplete, particularly for an extension towards gNBS. The present work aims to establish a multi-dimensional framework for future gNBS programs. An interdisciplinary expert panel comprising researchers from pediatric and adolescent medicine, human genetics, ethics, medical psychology, law, and patient representatives used a nominal group technique-like multi-stage consensus process to define criteria for gNBS, considering ethical, legal, and social implications, medical aspects, and patient perspectives. Overall, 18 criteria were developed, clustered into four subcategories: I. Clinical criteria (characteristics of the target disease); II. Diagnostic criteria (requirements of the test); III. Therapeutic-interventional criteria (prerequisites of the intervention); IV. Program management criteria (requirements of the program). Subcategories I-III define selection criteria for target diseases, subcategory IV defines criteria for how to establish and manage the program. In conclusion, this multi-dimensional framework serves as a well-balanced basis for developing thoroughly revised and internationally accepted consensus screening criteria.

While random X-chromosome inactivation in female cells of placental mammals silences one allele of the majority of X-chromosomal genes, a considerable fraction is only incompletely and variably inactivated. Human model systems to study the dynamics of incomplete X-inactivation are limited mostly to postmortem tissue, thereby disregarding developmental trajectories. Here, we used clonal human female induced pluripotent stem cells to track allele-specific expression of X-chromosomal genes along neural differentiation. We discovered dynamic reactivation and late-silencing of gene expression from the inactive X-chromosome leading to differentiation-induced locus- and lineage-specific usage of the two X-chromosomal alleles. In brain organoids modeling Opitz BBB/G syndrome, an X-linked neurodevelopmental disorder, reactivation of alleles from the inactive X-chromosome rescued cellular phenotypes and led to intermediate manifestations in female tissue. Taken together, our data demonstrate that alleles on the inactive X-chromosome can serve as a critical reservoir dynamically used during differentiation, thereby enhancing resilience of female neural tissue.

PURPOSE: Primary mitochondrial disorders (PMDs) are a clinically heterogeneous group of genetic disorders that can affect many tissues, with a broad phenotypic spectrum ranging from isolated organ involvement to severe early-onset multisystem disease. Visual loss from optic atrophy is a frequent clinical manifestation of mitochondrial cytopathies. This study aimed to identify the missing heritability in previously unsolved cases of suspected isolated or syndromic optic neuropathy. Based on three recent reports on biallelic NSUN3 variants causing early-onset PMD, we explored in detail the genetic and clinical spectrum of NSUN3-associated disease. METHODS: Affected individuals were analyzed by exome or genome sequencing. In silico variant analysis and functional assays were performed to investigate the consequences of the identified variants. Detailed phenotyping data were collected from medical records and direct questioning after the identification of candidate-likely pathogenic variants. RESULTS: Interrogation of exome and genome sequencing data led to the identification of six candidate NSUN3 variants in eight affected individuals from five unrelated families (including a previously reported case). A broad phenotypic spectrum was observed ranging from isolated optic atrophy to severe early-onset PMD. Identified NSUN3 variants impairing NSUN3 activity are located within the S-adenosylmethionine-dependent methyltransferases domain and loss of function variants were associated with a more severe phenotype. Remarkably, bilateral optic atrophy was a unifying clinical feature observed in almost all affected individuals. CONCLUSIONS: Pathogenic or likely pathogenic biallelic variants in NSUN3 disrupt mt-tRNAMet methylation and mitochondrial translation leading to mitochondrial disease ranging from mild isolated optic atrophy to a severe multisystemic phenotype with possible limited life expectancy.

BACKGROUND AND AIMS: Since described in 2015, NBAS-associated disease has emerged as an important cause of acute liver failure (ALF) in children. We analysed the variable expression, genotype-phenotype association, outcome and prognostic factors of the hepatic involvement. METHODS: Individuals with biallelic pathogenic NBAS variants were recruited within an international observational study, including new and previously published patients. RESULTS: We studied 230 individuals, including 13 previously unreported patients. The liver was the most frequently affected organ (63.4%), with 41.3% experiencing at least one ALF. The median age at onset was 0.9 years, the median age at last ALF 5 years, the latest ALF occurred at 24 years. Liver crises were triggered by febrile infections and presented with highly increased hepatic transaminases. Liver involvement varied significantly between the subgroups: 91.7% of patients with infantile liver failure syndrome type 2 and 88.9% of patients from the combined subgroup (variants affecting β-propeller domain) presented with ALF, whereas SOPH (stature, optic atrophy, Pelger-Huët anomaly) patients mostly had either no liver involvement (66.4%) or persistently elevated transaminases without ALF (28%). The rate of native liver survival was 83.9%; 16 individuals underwent liver transplantation and 24 died. CONCLUSION: Liver abnormalities are common and the leading cause of death in NBAS-associated disease. There is a clear genotype-phenotype association regarding the hepatic involvement. Liver crises occur primarily during infancy; however, early medical attention in case of febrile infections is necessary at all ages. Liver transplantation prevents ALF, but its risks must be weighed against the frequency and severity of liver crises decreasing with age.

PURPOSE: This systematic review aims to identify the factors that influence parents' decisions regarding pediatric diagnostic genetic testing (DT) and predictive genetic testing (PT). These factors are integrated into a conceptual decision-making model. Implications for genetic counseling, research, and ethics were derived. METHODS: PubMed, PsychInfo, WebofScience, and related references were searched for original publications between 2000 and 2023. The extracted factors were categorized using existing models. RESULTS: Of the 5843 publications, 56 met the inclusion criteria. The included studies differentiated between DT, traditional PT, and expanded PT and described factors affecting parental decisions to have the child genetically tested and to be informed about additional findings. Factors included (1) benefits/hopes, (2) worries/concerns, (3) values and beliefs, (4) individual circumstances, and (5) emotional states. CONCLUSION: Our work extends the existing empirical decision model of family decisions about genome sequencing to genetic testing in pediatrics in general, adding the categories of individual circumstances and emotional states. These factors can be further integrated into the Health Belief Model; the importance of emotional states is reflected in dual-process theories, such as the Fuzzy Trace Theory. Research is required on emotional states, differences between DT and PT, parents' decisions regarding result disclosure, and dyadic variables as decision-making predictors.

(Likely) pathogenic variants in NR2F1 are associated with Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS, OMIM #615722), a rare neurodevelopmental disorder. Patients present with a variety of symptoms, including intellectual disability, developmental delay, visual impairment, muscular hypotonia, seizures, and/or autistic features. Since it was first described in 2014, the phenotype has steadily expanded. However, there is limited information regarding the natural course of the disorder. Here, we present data on genetic variants and phenotype development of 47 individuals who responded to our questionnaire. A questionnaire was developed to assess the phenotype more comprehensively and to better understand the course of symptoms. In addition, families sent medical documents and photographs. To investigate the genotype-phenotype correlation in our cohort, we compared clinical features of two genotypically distinct groups (variants in the DNA-binding domain (DBD, n = 17) versus variants elsewhere in the gene (n = 30)). We observed a range of common symptoms including developmental delay, muscular hypotonia, optic atrophy, nystagmus, strabismus, autistic features, and thin corpus callosum on brain MRI. Overall, more improvement than worsening was reported. Individuals with variants in the DBD showed a higher prevalence of severe clinical features, such as infantile spasms (46.7% vs. 3.8%, p = 0.002) or nonverbality (50% vs. 3.4%, p = 0.0004), age at diagnosis was statistically significantly different between the two genotypic groups (mean 4.7 years vs. 8.9 years, p = 0.048). Our study confirms characteristic clinical features of BBSOAS. Variants in the DBD are associated with a more severe clinical phenotype. We found no evidence that the disease progresses; rather, several symptoms are reported to improve over time. However, prospective longitudinal studies are needed to further investigate disease progression.

Driven by technological innovations, newborn screening (NBS) panels have been expanded and the development of genomic NBS pilot programs is rapidly progressing. Decisions on disease selection for NBS are still based on the Wilson and Jungner (WJ) criteria published in 1968. Despite this uniform reference, interpretation of the WJ criteria and actual disease selection for NBS programs are highly variable. A systematic literature search [PubMED search "Wilson" AND "Jungner"; last search 16.07.22] was performed to evaluate the applicability of the WJ criteria for current and future NBS programs and the need for adaptation. By at least two reviewers, 105 publications (systematic literature search, N = 77; manual search, N = 28) were screened for relevant content and, finally, 38 publications were evaluated. Limited by the study design of qualitative text analysis, no statistical evaluation was performed, but a structured collection of reported aspects of criticism and proposed improvements was instead collated. This revealed a set of general limitations of the WJ criteria, such as imprecise terminology, lack of measurability and objectivity, missing pediatric focus, and absent guidance on program management. Furthermore, it unraveled specific aspects of criticism on clinical, diagnostic, therapeutic, and economical aspects. A major obstacle was found to be the incompletely understood natural history and phenotypic diversity of rare diseases prior to NBS implementation, resulting in uncertainty about case definition, risk stratification, and indications for treatment. This gap could be closed through the systematic collection and evaluation of real-world evidence on the quality, safety, and (cost-)effectiveness of NBS, as well as the long-term benefits experienced by screened individuals. An integrated NBS public health program that is designed to continuously learn would fulfil these requirements, and a multi-dimensional framework for future NBS programs integrating medical, ethical, legal, and societal perspectives is overdue.

Genomic newborn screening (gNBS) is on the horizon given the decreasing costs of sequencing and the advanced understanding of the impact of genetic variants on health and diseases. Key to ongoing gNBS pilot studies is the selection of target diseases and associated genes to be included. In this study, we present a comprehensive analysis of seven published gene-disease lists from gNBS studies, evaluating gene-disease count, composition, group proportions, and ClinGen curations of individual disorders. Despite shared selection criteria, we observe substantial variation in total gene count (median 480, range 237-889) and disease group composition. An intersection was identified for 53 genes, primarily inherited metabolic diseases (83%, 44/53). Each study investigated a subset of exclusive gene-disease pairs, and the total number of exclusive gene-disease pairs was positively correlated with the total number of genes included per study. While most pairs receive "Definitive" or "Strong" ClinGen classifications, some are labeled as "Refuted" (n = 5) or "Disputed" (n = 28), particularly in genetic cardiac diseases. Importantly, 17%-48% of genes lack ClinGen curation. This study underscores the current absence of consensus recommendations for selection criteria for target diseases for gNBS resulting in diversity in proposed gene-disease pairs, their coupling with gene variations and the use of ClinGen curation. Our findings provide crucial insights into the selection of target diseases and accompanying gene variations for future gNBS program, emphasizing the necessity for ongoing collaboration and discussion about criteria harmonization for panel selection to ensure the screening's objectivity, integrity, and broad acceptance.

The objective of the study is to evaluate the evolving phenotype and genetic spectrum of patients with succinic semialdehyde dehydrogenase deficiency (SSADHD) in long-term follow-up. Longitudinal clinical and biochemical data of 22 pediatric and 9 adult individuals with SSADHD from the patient registry of the International Working Group on Neurotransmitter related Disorders (iNTD) were studied with in silico analyses, pathogenicity scores and molecular modeling of ALDH5A1 variants. Leading initial symptoms, with onset in infancy, were developmental delay and hypotonia. Year of birth and specific initial symptoms influenced the diagnostic delay. Clinical phenotype of 26 individuals (median 12 years, range 1.8-33.4 years) showed a diversifying course in follow-up: 77% behavioral problems, 76% coordination problems, 73% speech disorders, 58% epileptic seizures and 40% movement disorders. After ataxia, dystonia (19%), chorea (11%) and hypokinesia (15%) were the most frequent movement disorders. Involvement of the dentate nucleus in brain imaging was observed together with movement disorders or coordination problems. Short attention span (78.6%) and distractibility (71.4%) were the most frequently behavior traits mentioned by parents while impulsiveness, problems communicating wishes or needs and compulsive behavior were addressed as strongly interfering with family life. Treatment was mainly aimed to control epileptic seizures and psychiatric symptoms. Four new pathogenic variants were identified. In silico scoring system, protein activity and pathogenicity score revealed a high correlation. A genotype/phenotype correlation was not observed, even in siblings. This study presents the diversifying characteristics of disease phenotype during the disease course, highlighting movement disorders, widens the knowledge on the genotypic spectrum of SSADHD and emphasizes a reliable application of in silico approaches.

The X-linked form of Opitz BBB/G syndrome (OS) is a monogenic disorder in which symptoms are established early during embryonic development. OS is caused by pathogenic variants in the X-linked gene MID1 Disease-associated variants are distributed across the entire gene locus, except for the N-terminal really interesting new gene (RING) domain that encompasses the E3 ubiquitin ligase activity. By using genome-edited human induced pluripotent stem cell lines, we here show that absence of isoforms containing the RING domain of MID1 causes severe patterning defects in human brain organoids. We observed a prominent neurogenic deficit with a reduction in neural tissue and a concomitant increase in choroid plexus-like structures. Transcriptome analyses revealed a deregulation of patterning pathways very early on, even preceding neural induction. Notably, the observed phenotypes starkly contrast with those observed in MID1 full-knockout organoids, indicating the presence of a distinct mechanism that underlies the patterning defects. The severity and early onset of these phenotypes could potentially account for the absence of patients carrying pathogenic variants in exon 1 of the MID1 gene coding for the N-terminal RING domain.

Hao-Fountain syndrome (HAFOUS, OMIM: #616863) is a neurodevelopmental disorder caused by pathogenic variants in the gene USP7 coding for USP7, a protein involved in several crucial cellular homeostatic mechanisms and the recently described MUST complex. The phenotype of HAFOUS is insufficiently understood, yet there is a great need to better understand the spectrum of disease, genotype-phenotype correlations, and disease trajectories. We now present a larger cohort of 32 additional individuals and provide further clinical information about six previously reported individuals. A questionnaire-based study was performed to characterize the phenotype of Hao-Fountain syndrome more clearly, to highlight new traits, and to better distinguish the disease from related neurodevelopmental disorders. In addition to confirming previously described features, we report hyperphagia and increased body weight in a subset of individuals. HAFOUS patients present an increased rate of birth complications, congenital anomalies, and abnormal pain thresholds. Speech impairment emerges as a potential hallmark of Hao-Fountain syndrome. Cognitive testing reports reveal borderline intellectual functioning on average, although some individuals score in the range of intellectual disability. Finally, we created a syndrome-specific severity score. This score neither indicates a sex- nor age-specific difference of clinical severity, yet highlights a more severe outcome when amino acid changes colocalize to the catalytic domain of the USP7 protein.

BACKGROUND: Pathogenic variants in the zinc finger protein coding genes are rare causes of intellectual disability and congenital malformations. Mutations in the ZNF148 gene causing GDACCF syndrome (global developmental delay, absent or hypoplastic corpus callosum, dysmorphic facies; MIM #617260) have been reported in five individuals so far. METHODS: As a result of an international collaboration using GeneMatcher Phenome Central Repository and personal communications, here we describe the clinical and molecular genetic characteristics of 22 previously unreported individuals. RESULTS: The core clinical phenotype is characterised by developmental delay particularly in the domain of speech development, postnatal growth retardation, microcephaly and facial dysmorphism. Corpus callosum abnormalities appear less frequently than suggested by previous observations. The identified mutations concerned nonsense or frameshift variants that were mainly located in the last exon of the ZNF148 gene. Heterozygous deletion including the entire ZNF148 gene was found in only one case. Most mutations occurred de novo, but were inherited from an affected parent in two families. CONCLUSION: The GDACCF syndrome is clinically diverse, and a genotype-first approach, that is, exome sequencing is recommended for establishing a genetic diagnosis rather than a phenotype-first approach. However, the syndrome may be suspected based on some recurrent, recognisable features. Corpus callosum anomalies were not as constant as previously suggested, we therefore recommend to replace the term 'GDACCF syndrome' with 'ZNF148-related neurodevelopmental disorder'.

The autosomal recessive defect of aromatic L-amino acid decarboxylase (AADC) leads to a severe neurological disorder with manifestation in infancy due to a pronounced, combined deficiency of dopamine, serotonin and catecholamines. The success of conventional drug treatment is very limited, especially in patients with a severe phenotype. The development of an intracerebral AAV2-based gene delivery targeting the putamen or substantia nigra started more than 10 years ago. Recently, the putaminally-delivered construct, Eladocagene exuparvovec has been approved by the European Medicines Agency and by the British Medicines and Healthcare products Regulatory Agency. This now available gene therapy provides for the first time also for AADC deficiency (AADCD) a causal therapy, leading this disorder into a new therapeutic era. By using a standardized Delphi approach members of the International Working Group on Neurotransmitter related Disorders (iNTD) developed structural requirements and recommendations for the preparation, management and follow-up of AADC deficiency patients who undergo gene therapy. This statement underlines the necessity of a framework for a quality-assured application of AADCD gene therapy including Eladocagene exuparvovec. Treatment requires prehospital, inpatient and posthospital care by a multidisciplinary team in a specialized and qualified therapy center. Due to lack of data on long-term outcomes and the comparative efficacy of alternative stereotactic procedures and brain target sites, a structured follow-up plan and systematic documentation of outcomes in a suitable, industry-independent registry study are necessary.

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. Die Anwendung von Hochdurchsatz-Sequenziermethoden für ein populationsbasiertes genomisches Neugeborenenscreening (gNBS) bietet zahlreiche Chancen für die Verbesserung der Bevölkerungsgesundheit. Ein solches würde ermöglichen, die Diagnose zahlreicher genetischer Erkrankungen bereits in einem frühen, präsymptomatischen Stadium zu stellen, und böte große Flexibilität bei der Auswahl und Erweiterung von Zielkrankheiten. National und international werden daher Anstrengungen unternommen, um die ethischen, rechtlichen, sozialen, psychologischen und technischen Aspekte des gNBS zu untersuchen. Neben den vielen Chancen existieren auch zahlreiche Herausforderungen und noch offene Fragen: Wann und wie sollten Erziehungsberechtigte über ein solches Screening informiert werden? Auf welche Krankheiten sollte gescreent werden? Wie soll mit Zufallsbefunden oder der Feststellung einer genetischen Veranlagung umgegangen werden? Sollen die Daten langfristig gespeichert werden und, wenn ja, wie kann dies sicher geschehen? Unter der Voraussetzung einer angemessenen Rechtsgrundlage und eines transparenten Einwilligungsprozesses hat das genomische Neugeborenenscreening das Potenzial, die Art und Weise, wie wir angeborene Krankheiten diagnostizieren, grundlegend zu verändern. Es gibt jedoch noch viel zu tun. Um ein gutes Verständnis und eine ausreichende Akzeptanz des gNBS bei allen Beteiligten zu erreichen und so den Nutzen für die Bevölkerung zu maximieren, ist ein öffentlicher Diskurs über die Möglichkeiten und Grenzen des gNBS von zentraler Bedeutung. Dieser Beitrag hat das Ziel, einen Überblick über die innovativen technischen Entwicklungen in der Humangenetik, nationale und internationale Forschungsansätze sowie über Chancen und Herausforderungen bei der Entwicklung eines genomischen Neugeborenenscreenings zu geben.

The widespread use of high-throughput sequencing techniques is leading to a rapidly increasing number of disease-associated variants of unknown significance and candidate genes. Integration of knowledge concerning their genetic, protein as well as functional and conservational aspects is necessary for an exhaustive assessment of their relevance and for prioritization of further clinical and functional studies investigating their role in human disease. To collect the necessary information, a multitude of different databases has to be accessed and data extraction from the original sources commonly is not user-friendly and requires advanced bioinformatics skills. This leads to a decreased data accessibility for a relevant number of potential users such as clinicians, geneticist, and clinical researchers. Here, we present aRgus (https://argus.urz.uni-heidelberg.de/), a standalone webtool for simple extraction and intuitive visualization of multi-layered gene, protein, variant, and variant effect prediction data. aRgus provides interactive exploitation of these data within seconds for any known gene of the human genome. In contrast to existing online platforms for compilation of variant data, aRgus complements visualization of chromosomal exon-intron structure and protein domain annotation with ClinVar and gnomAD variant distributions as well as position-specific variant effect prediction score modeling. aRgus thereby enables timely assessment of protein regions vulnerable to variation with single amino acid resolution and provides numerous applications in variant and protein domain interpretation as well as in the design of in vitro experiments.

PURPOSE: This study aimed to define the genotypic and phenotypic spectrum of reversible acute liver failure (ALF) of infancy resulting from biallelic pathogenic TRMU variants and determine the role of cysteine supplementation in its treatment. METHODS: Individuals with biallelic (likely) pathogenic variants in TRMU were studied within an international retrospective collection of de-identified patient data. RESULTS: In 62 individuals, including 30 previously unreported cases, we described 47 (likely) pathogenic TRMU variants, of which 17 were novel, and 1 intragenic deletion. Of these 62 individuals, 42 were alive at a median age of 6.8 (0.6-22) years after a median follow-up of 3.6 (0.1-22) years. The most frequent finding, occurring in all but 2 individuals, was liver involvement. ALF occurred only in the first year of life and was reported in 43 of 62 individuals; 11 of whom received liver transplantation. Loss-of-function TRMU variants were associated with poor survival. Supplementation with at least 1 cysteine source, typically N-acetylcysteine, improved survival significantly. Neurodevelopmental delay was observed in 11 individuals and persisted in 4 of the survivors, but we were unable to determine whether this was a primary or a secondary consequence of TRMU deficiency. CONCLUSION: In most patients, TRMU-associated ALF was a transient, reversible disease and cysteine supplementation improved survival.

OBJECTIVES: Pathogenic biallelic variants in PCK1 coding for the cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C) cause PEPCK-C deficiency, a rare disorder of gluconeogenesis presenting with hypoglycemia, lactic acidosis, and hepatopathy. To date, there has been no systematic analysis of its phenotypic, biochemical, and genetic spectrum. METHODS: All currently published individuals and a novel patient with genetically confirmed PEPCK-C deficiency were included. Clinical, biochemical, and genetic findings were analyzed. Protein and in-silico prediction score modeling was applied to analyze potential variant effects. RESULTS: Thirty-two individuals from 25 families were found, including one previously unreported patient. The typical biochemical pattern was hypoglycemia triggered by catabolic situations, elevated urinary concentrations of tricarboxylic acid cycle metabolites, mildly elevated alanine and aspartate aminotransferase and elevated lactate concentrations in serum. Plasma glutamine concentrations were elevated in some patients and may be a suitable marker for newborn screening. With adequate treatment, biochemical abnormalities usually normalized following a hypoglycemic episode. Symptom onset usually occurred in infancy with a broad range from neonatal age to adulthood. Regardless of the genotype, different phenotypes with a broad clinical spectrum were found. To date, eight genotypes with nine different PCK1 variants were identified, of which alleles with the recurrent variant c.925G > A; p.(Gly309Arg) are predominant and appear to be endemic in the Finnish population. Protein modeling suggests altered manganese- and substrate-binding as superordinate pathomechanisms. CONCLUSIONS: Environmental factors appear to be the main determinant for the phenotype in patients with biallelic variants in PCK1. Based on the biochemical pattern, PEPCK-C deficiency is a recognizable cause of childhood hypoglycemia. It is a treatable disease and early diagnosis is important to prevent metabolic derailment and morbidity. Newborn screening can identify at least a sub-cohort of affected individuals through elevated glutamine concentrations in dry blood.

(1) Background: Phenotypic diversity and long-term health outcomes of individuals with urea cycle disorders (UCDs) have been described in detail. However, there is limited information on the burden on affected families. (2) Methods: To evaluate the family burden in parents with children suffering from UCDs, we used validated questionnaires. Socio-demographic characteristics were evaluated, and an adapted version of the Parental Need Scale for Rare Diseases questionnaire was used. The survey was conducted in families of UCD patients cared for at the University Children's Hospital Heidelberg. (3) Results: From April to November 2021, 59 participants were interviewed (mothers n = 34, fathers n = 25). The affected patients most frequently suffered from ornithine transcarbamylase deficiency (OTC-D) (female n = 12, male n = 12), followed by argininosuccinate synthetase deficiency (ASS-D, n = 13) and argininosuccinate lyase deficiency (ASL-D, n = 8). About one-third of the participants were "dissatisfied" or "extremely dissatisfied" with health professionals' disease knowledge. In addition, 30% of the participants reported a medium or high need for "additional information on the development of their children", and 44% reported a medium or high need "for information on available services". A majority of 68% reported a need for additional support regarding services such as support groups (42%) or psychological counseling (29%). (4) Conclusions: Our study indicates that there is an unmet need for sufficient information about the development of children with UCDs, as well as for information about available support services for families with UCD patients. Furthermore, the results highlight the importance of establishing or improving family-centered care approaches. This pilot study may serve as a template for the assessment of the family burden associated with other inherited metabolic diseases.

TUBA1A tubulinopathy is a rare neurodevelopmental disorder associated with brain malformations as well as early-onset and intractable epilepsy. As pathomechanisms and genotype-phenotype correlations are not completely understood, we aimed to provide further insights into the phenotypic and genetic spectrum. We here present a multicenter case series of ten unrelated individuals from four European countries using systematic MRI re-evaluation, protein structure analysis, and prediction score modeling. In two cases, pregnancy was terminated due to brain malformations. Amongst the eight living individuals, the phenotypic range showed various severity. Global developmental delay and severe motor impairment with tetraparesis was present in 63% and 50% of the subjects, respectively. Epilepsy was observed in 75% of the cases, which showed infantile onset in 83% and a refractory course in 50%. One individual presented a novel TUBA1A-associated electroclinical phenotype with evolvement from early myoclonic encephalopathy to continuous spike-and-wave during sleep. Neuroradiological features comprised a heterogeneous spectrum of cortical and extracortical malformations including rare findings such as cobblestone lissencephaly and subcortical band heterotopia. Two individuals developed hydrocephalus with subsequent posterior infarction. We report four novel and five previously published TUBA1A missense variants whose resulting amino acid substitutions likely affect longitudinal, lateral, and motor protein interactions as well as GTP binding. Assessment of pathogenic and benign variant distributions in synopsis with prediction scores revealed sections of variant enrichment and intolerance to missense variation. We here extend the clinical, neuroradiological, and genetic spectrum of TUBA1A tubulinopathy and provide insights into residue-specific pathomechanisms and genotype-phenotype correlations.

BACKGROUND: Given the novelty of gene replacement therapy with onasemnogene abeparvovec in spinal muscular atrophy, efficacy and safety data are limited, especially for children older than 24 months, those weighing more than 8·5 kg, and those who have received nusinersen. We aimed to provide real-world data on motor function and safety after gene replacement therapy in different patient subgroups. METHODS: We did a protocol-based, multicentre prospective observational study between Sept 21, 2019, and April 20, 2021, in 18 paediatric neuromuscular centres in Germany and Austria. All children with spinal muscular atrophy types 1 and 2 receiving onasemnogene abeparvovec were included in our cohort, and there were no specific exclusion criteria. Motor function was assessed at the time of gene replacement therapy and 6 months afterwards, using the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) and Hammersmith Functional Motor Scale-Expanded (HFMSE) scores. Additionally, in children pretreated with nusinersen, motor function was assessed before and after treatment switch. Off-target adverse events were analysed with a focus on liver function, thrombocytopaenia, and potential cardiotoxicity. FINDINGS: 76 children (58 pretreated with nusinersen and 18 who were nusinersen naive) with spinal muscular atrophy were treated with onasemnogene abeparvovec at a mean age of 16·8 months (range 0·8-59·0, IQR 9-23) and a mean weight of 9·1 kg (range 4·0-15·0, IQR 7·4-10·6). In 60 patients with available data, 49 had a significant improvement on the CHOP-INTEND score (≥4 points) and HFMSE score (≥3 points). Mean CHOP INTEND scores increased significantly in the 6 months after therapy in children younger than 8 months (n=16; mean change 13·8 [SD 8·5]; p<0·0001) and children aged between 8 and 24 months (n=34; 7·7 [SD 5·2]; p<0·0001), but not in children older than 24 months (n=6; 2·5 [SD 5·2]; p=1·00). In the 45 children pretreated with nusinersen and had available data, CHOP INTEND score increased by 8·8 points (p=0·0003) at 6 months after gene replacement therapy. No acute complications occurred during infusion of onasemnogene abeparvovec, but 56 (74%) patients had treatment-related side-effects. Serious adverse events occurred in eight (11%) children. Liver enzyme elevation significantly increased with age and weight at treatment. Six (8%) patients developed acute liver dysfunction. Other adverse events included pyrexia (n=47 [62%]), vomiting or loss of appetite (41 [54%]), and thrombocytopenia (n=59 [78%]). Prednisolone treatment was significantly prolonged with a mean duration of 15·7 weeks (IQR 9-19), mainly due to liver enzyme elevation. Cardiac adverse events were rare; only two patients had abnormal echocardiogram and echocardiography findings. INTERPRETATION: This study provides class IV evidence that children with spinal muscular atrophy aged 24 months or younger and patients pretreated with nusinersen significantly benefit from gene replacement therapy, but adverse events can be severe and need to be closely monitored. FUNDING: None. TRANSLATION: For the German translation of the abstract see Supplementary Materials section.

Compound heterozygosis is the most diffuse and hardly to tackle condition in aromatic amino acid decarboxylase (AADC) deficiency, a genetic disease leading to severe neurological impairment. Here, by using an appropriate vector, we succeeded in obtaining high yields of AADC protein and characterizing two new heterodimers, T69M/S147R and C281W/M362T, detected in two AADC deficiency patients. We performed an extensive biochemical characterization of the heterodimeric recombinant proteins and of the related homodimers, by a combination of dichroic and fluorescence spectroscopy and activity assays together with bioinformatic analyses. We found that T69M/S147R exhibits negative complementation in terms of activity but it is more stable than the average of the homodimeric counterparts. The heterodimer C281W/M362T retains a nearly good catalytic efficiency, whereas M362T homodimer is less affected and C281W homodimer is recovered as insoluble. These results, which are consistent with the related phenotypes, and the data emerging from previous studies, suggest that the severity of AADC deficiency is not directly explained by positive or negative complementation phenomena, but rather depends on: i) the integrity of one or both active sites; ii) the structural and functional properties of the entire pool of AADC proteins expressed. Overall, this integrated and cross-sectional approach enables proper characterization and depicts the functional result of subunit interactions in the dimeric structure and will help to elucidate the physio-pathological mechanisms in AADC deficiency.

Inherited disorders of neurotransmitter metabolism are a group of rare diseases, which are caused by impaired synthesis, transport, or degradation of neurotransmitters or cofactors and result in various degrees of delayed or impaired psychomotor development. To assess the effect of neurotransmitter deficiencies on intelligence, quality of life, and behavior, the data of 148 patients in the registry of the International Working Group on Neurotransmitter Related Disorders (iNTD) was evaluated using results from standardized age-adjusted tests and questionnaires. Patients with a primary disorder of monoamine metabolism had lower IQ scores (mean IQ 58, range 40-100) within the range of cognitive impairment (<70) compared to patients with a BH4 deficiency (mean IQ 84, range 40-129). Short attention span and distractibility were most frequently mentioned by parents, while patients reported most frequently anxiety and distractibility when asked for behavioral traits. In individuals with succinic semialdehyde dehydrogenase deficiency, self-stimulatory behaviors were commonly reported by parents, whereas in patients with dopamine transporter deficiency, DNAJC12 deficiency, and monoamine oxidase A deficiency, self-injurious or mutilating behaviors have commonly been observed. Phobic fears were increased in patients with 6-pyruvoyltetrahydropterin synthase deficiency, while individuals with sepiapterin reductase deficiency frequently experienced communication and sleep difficulties. Patients with BH4 deficiencies achieved significantly higher quality of life as compared to other groups. This analysis of the iNTD registry data highlights: (a) difference in IQ and subdomains of quality of life between BH4 deficiencies and primary neurotransmitter-related disorders and (b) previously underreported behavioral traits.

SYNCRIP encodes for the Synaptotagmin-binding cytoplasmic RNA-interacting protein, involved in RNA-binding and regulation of multiple cellular pathways. It has been proposed as a candidate gene for neurodevelopmental disorders (NDDs) with autism spectrum disorder (ASD), intellectual disability (ID), and epilepsy. We ascertained genetic, clinical, and neuroradiological data of three additional individuals with novel de novo SYNCRIP variants. All individuals had ID. Autistic features were observed in two. One individual showed myoclonic-atonic epilepsy. Neuroradiological features comprised periventricular nodular heterotopia and widening of subarachnoid spaces. Two frameshift variants in the more severely affected individuals, likely result in haploinsufficiency. The third missense variant lies in the conserved RNA recognition motif (RRM) 2 domain likely affecting RNA-binding. Our findings support the importance of RRM domains for SYNCRIP functionality and suggest genotype-phenotype correlations. Our study provides further evidence for a SYNCRIP-associated NDD characterized by ID and ASD sporadically accompanied by malformations of cortical development and myoclonic-atonic epilepsy.

Mevalonic aciduria (MVA) and hyperimmunoglobulinemia D syndrome (MKD/HIDS) are disorders of cholesterol biosynthesis caused by variants in the MVK gene and characterized by increased urinary excretion of mevalonic acid. So far, 30 MVA patients have been reported, suffering from recurrent febrile crises and neurologic impairment. Here, we present an in-depth analysis of the phenotypic spectrum of MVA and provide an in-silico pathogenicity model analysis of MVK missense variants. The phenotypic spectrum of 11 MVA patients (age range 0-51 years) registered in the Unified European Registry for Inherited Metabolic Disorders database was systematically analyzed using terms of the Human Phenotype Ontology. Biochemical, radiological as well as genetic characteristics were investigated. Six of eleven patients have reached adulthood and four have reached adolescence. One of the adolescent patients died at the age of 16 years and one patient died shortly after birth. Symptoms started within the first year of life, including episodic fever, developmental delay, ataxia, and ocular involvement. We also describe a case with absence of symptoms despite massive excretion of mevalonic acid. Pathogenic variants causing MVA cluster within highly conserved regions, which are involved in mevalonate and ATP binding. The phenotype of adult and adolescent MVA patients is more heterogeneous than previously assumed. Outcome varies from an asymptomatic course to early death. MVK variants cluster in functionally important and highly conserved protein domains and show high concordance regarding their expected pathogenicity.

OBJECTIVE: To investigate reported extreme temperature-related catastrophic events and associated mortality on the European continent including the Russian Federation. DESIGN: Cross-sectional respecting Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria. SETTINGS: Data source: Emergency Events Database (EM-DAT). PARTICIPANTS: Search criteria: location-European continent including Russian Federation, time-years 1988 until 2019 (close of database 12 July 2019), catastrophic events-extreme temperatures. PRIMARY OUTCOME MEASURES: Numbers of heat waves, cold waves, severe winter conditions and associated number of deaths, overall, and per country and year, respecting STROBE criteria. RESULTS: The most frequent type of the 243 events recorded in EM-DAT were cold waves (54.7%). However, cold waves and severe winter conditions only accounted for 6460 deaths (4.5%), while heat waves were associated with 137 533 deaths (95.5%). The five most severe heat waves in 2003, 2006, 2010, 2013 and 2015 were associated with a total of 135 089 deaths. The most severe heat waves were geographically distributed over the Russian Federation (2010), as well as France, Italy, Spain and Germany, each in 2003. CONCLUSION: Although cold waves are more frequently reported in EM-DAT, heat waves are the major cause for temperature-related deaths. In order to better protect the public, it is important to address resiliency and vulnerability of populations at risk and age groups.

Pathogenic variants in KCNA2, encoding for the voltage-gated potassium channel Kv1.2, have been identified as the cause for an evolving spectrum of neurological disorders. Affected individuals show early-onset developmental and epileptic encephalopathy, intellectual disability, and movement disorders resulting from cerebellar dysfunction. In addition, individuals with a milder course of epilepsy, complicated hereditary spastic paraplegia, and episodic ataxia have been reported. By analyzing phenotypic, functional, and genetic data from published reports and novel cases, we refine and further delineate phenotypic as well as functional subgroups of KCNA2-associated disorders. Carriers of variants, leading to complex and mixed channel dysfunction that are associated with a gain- and loss-of-potassium conductance, more often show early developmental abnormalities and an earlier onset of epilepsy compared to individuals with variants resulting in loss- or gain-of-function. We describe seven additional individuals harboring three known and the novel KCNA2 variants p.(Pro407Ala) and p.(Tyr417Cys). The location of variants reported here highlights the importance of the proline(405)-valine(406)-proline(407) (PVP) motif in transmembrane domain S6 as a mutational hotspot. A novel case of self-limited infantile seizures suggests a continuous clinical spectrum of KCNA2-related disorders. Our study provides further insights into the clinical spectrum, genotype-phenotype correlation, variability, and predicted functional impact of KCNA2 variants.

Succinic semialdehyde dehydrogenase deficiency (SSADHD) is a rare, monogenic disorder affecting the degradation of the main inhibitory neurotransmitter γ-amino butyric acid (GABA). Pathogenic variants in the ALDH5A1 gene that cause an enzymatic dysfunction of succinic semialdehyde dehydrogenase (SSADH) lead to an accumulation of potentially toxic metabolites, including γ-hydroxybutyrate (GHB). Here, we present a patient with a severe phenotype of SSADHD caused by a novel genetic variant c.728T > C that leads to an exchange of leucine to proline at residue 243, located within the highly conserved nicotinamide adenine dinucleotide (NAD)+ binding domain of SSADH. Proline harbors a pyrrolidine within its side chain known for its conformational rigidity and disruption of protein secondary structures. We investigate the effect of this novel variant in vivo, in vitro, and in silico. We furthermore examine the mutational spectrum of all previously described disease-causing variants and computationally assess all biologically possible missense variants of ALDH5A1 to identify mutational hotspots.

BACKGROUND: Pulmonary alveolar proteinosis (PAP) is a heterogeneous condition with more than 100 different underlying disorders that need to be differentiated to target therapeutic options, which are generally limited. METHODS: The clinical course of two brothers with pathogenic variants in the methionyl-tRNA synthetase (MARS)1 gene was compared to previously published patients. Functional studies in patient-derived fibroblasts were performed and therapeutic options evaluated. RESULTS: The younger brother was diagnosed with PAP at the age of 1 year. Exome sequencing revealed the homozygous MARS1 variant p.(Arg598Cys), leading to interstitial lung and liver disease (ILLD). At 2 years of age, following surgery hypoglycemia was detected, the pulmonary condition deteriorated, and the patient developed multiorgan failure. Six therapeutic whole lung lavages (WLL) were necessary to improve respiratory insufficiency. Methionine supplementation was started and a high protein diet ensured, leading to complete respiratory recovery. The older brother, homozygous for the same MARS1 variant, had a long-known distinct eating preference of methionine-rich food and showed a less severe clinical phenotype. Decreased aminoacylation activity confirmed the pathogenicity of p.(Arg598Cys) in vitro. In agreement with our review of currently published ILLD patients, the presence of hepatopathy, developmental delay, muscular hypotonia, and anemia support the multisystemic character of the disease. CONCLUSIONS: Catabolic events can provoke a severe deterioration of the pulmonary situation in ILLD with a need for repetitive WLL. Although the precise role of oral methionine supplementation and high protein intake are unknown, we observed an apparent treatment benefit, which needs to be evaluated systematically in controlled trials.

PURPOSE: Biallelic variants in LARS1, coding for the cytosolic leucyl-tRNA synthetase, cause infantile liver failure syndrome 1 (ILFS1). Since its description in 2012, there has been no systematic analysis of the clinical spectrum and genetic findings. METHODS: Individuals with biallelic variants in LARS1 were included through an international, multicenter collaboration including novel and previously published patients. Clinical variables were analyzed and functional studies were performed in patient-derived fibroblasts. RESULTS: Twenty-five individuals from 15 families were ascertained including 12 novel patients with eight previously unreported variants. The most prominent clinical findings are recurrent elevation of liver transaminases up to liver failure and encephalopathic episodes, both triggered by febrile illness. Magnetic resonance image (MRI) changes during an encephalopathic episode can be consistent with metabolic stroke. Furthermore, growth retardation, microcytic anemia, neurodevelopmental delay, muscular hypotonia, and infection-related seizures are prevalent. Aminoacylation activity is significantly decreased in all patient cells studied upon temperature elevation in vitro. CONCLUSION: ILFS1 is characterized by recurrent elevation of liver transaminases up to liver failure in conjunction with abnormalities of growth, blood, nervous system, and musculature. Encephalopathic episodes with seizures can occur independently from liver crises and may present with metabolic stroke.

BACKGROUND: Aromatic L-amino acid decarboxylase (AADC) deficiency is a primary neurotransmitter defect of the biosynthesis of catecholamines and serotonin. The phenotype consists of varying degrees of neurological impairment, including motor and non-motor symptoms. Treatment outcomes correlate with the time point of diagnosis and treatment initiation; therefore, reliable diagnostic markers are necessary. Increased vanillactic acid (VLA) concentrations in the analysis of organic acids in urine have been reported in AADC deficiency. However, this elevation is often subtle and easily missed. In this study, we evaluate the semi-quantitative determination of VLA and vanillylmandelic acid (VMA) concentrations and establish the ratio of a VLA/VMA as a novel diagnostic marker for AADC deficiency. METHODS: Urine samples obtained from 10,095 non-AADC deficient controls and 14 confirmed AADC deficient patients were used for organic acid analysis by liquid-liquid extraction of the acidified samples and gas chromatographic-mass spectrometric separation after trimethylsilylation. The semi-quantitative determination of VLA and VMA concentrations and the calculation of a VLA/VMA ratio were evaluated as a diagnostic marker for AADC deficiency. RESULTS: The mean VLA and VMA concentrations in 10,095 non-AADCD samples was 0.3 mmol/mol creatinine (SD = 1.18, range 0-57.79) and 5.59 mmol/mol creatinine (SD = 3.87, range 0.04-60.62), respectively. The mean concentration of VLA in 14 patient-derived samples was 10.24 mmol/mol creatinine, (SD = 11.58, range = 0.37-33.06) and 0.45 mmol/mol creatinine for VMA (SD = 0.29, range 0.11-1.27). The mean VLA/VMA ratio in non-AADC controls was 0.07 (SD = 0.37, range 0.0-23.24), whereas AADC deficient patients revealed a mean VLA/VMA ratio of 23.16 (SD = 22.83, range 0.97-74.1). The VLA/VMA ratio thus allows a reliable identification of patients with AADC deficiency, especially in the young age cohort as it decreases with age. To take this into account, age-adjusted thresholds have been developed. CONCLUSION: Determination of individual concentrations of VLA and VMA in urine does not allow a reliable diagnosis of AADC deficiency. In this study, we could demonstrate that a semi-quantitative analysis of organic acids in urine allows the formation of metabolite ratios and that the VLA/VMA ratio is a reliable, easily accessible, new parameter for the diagnosis of AADC deficiency.

Succinic semialdehyde dehydrogenase deficiency (SSADH-D) is a genetic disorder that results from the aberrant metabolism of the neurotransmitter γ-amino butyric acid (GABA). The disease is caused by impaired activity of the mitochondrial enzyme succinic semialdehyde dehydrogenase. SSADH-D manifests as varying degrees of mental retardation, autism, ataxia, and epileptic seizures, but the clinical picture is highly heterogeneous. So far, there is no approved curative therapy for this disease. In this review, we briefly summarize the molecular genetics of SSADH-D, the past and ongoing clinical trials, and the emerging features of the molecular pathogenesis, including redox imbalance and mitochondrial dysfunction. The main aim of this review is to discuss the potential of further therapy approaches that have so far not been tested in SSADH-D, such as pharmacological chaperones, read-through drugs, and gene therapy. Special attention will also be paid to elucidating the role of patient advocacy organizations in facilitating research and in the communication between researchers and patients.

Aromatic l-amino-acid decarboxylase (AADC) deficiency is an inherited disorder of biogenic amine metabolism with a broad neurological phenotype. The clinical symptoms overlap with other diseases resulting in an often delayed diagnosis. Innovative disease-changing treatment options, particularly gene therapy, have emphasised the need for an early diagnosis. We describe the first method for 3-O-methyldopa (3-OMD) analysis in dried blood spots (DBS) suitable for high throughput newborn screening (NBS). We established a novel tandem mass spectrometry method to quantify 3-OMD in DBS and successfully tested it in 38 888 unaffected newborns, 14 heterozygous DDC variant carriers, seven known AADC deficient patients, and 1079 healthy control subjects. 3-OMD concentrations in 38 888 healthy newborns revealed a mean of 1.16 μmol/L (SD = 0.31, range 0.31-4.6 μmol/L). 1079 non-AADC control subjects (0-18 years) showed a mean 3-OMD concentration of 0.78 μmol/L (SD = 1.75, range 0.24-2.36 μmol/L) with a negative correlation with age. Inter- and intra-assay variability was low, and 3-OMD was stable over 32 days under different storage conditions. We identified seven confirmed AADC deficient patients (mean 3-OMD 9.88 μmol/L [SD = 13.42, range 1.82-36.93 μmol/L]). The highest concentration of 3-OMD was found in a NBS filter card of a confirmed AADC deficient patient with a mean 3-OMD of 35.95 μmol/L. 14 DDC variant carriers showed normal 3-OMD concentrations. We demonstrate a novel high-throughput method to measure 3-OMD in DBS, which allows integration in existing NBS programs enabling early diagnosis of AADC deficiency.

Neurotransmitter deficiencies are rare neurological disorders with clinical onset during childhood. The disorders are caused by genetic defects in the enzymes involved in synthesis, degradation, or transport of neurotransmitters or by defects in the cofactor biosynthesis such as tetrahydrobiopterin (BH4). With the newly described DNAJC12 deficiency, a chaperon-associated neurotransmitter disorder, the pathophysiological spectrum has been broadened. All deficiencies result in a lack of monoamine neurotransmitters, especially dopamine and its products, with a subset leading to decreased levels of serotonin. Symptoms can occur already in the neonatal period. Classical signs are hypotonia, movement disorders, autonomous dysregulations, and impaired development. Diagnosis depends on quantitative detection of neurotransmitters in cerebrospinal fluid, since peripheral markers in blood or urine are less reliable. Treatment is based on supplementation of the missing neurotransmitter precursors or restoring deficient cofactors for endogenous enzymatic synthesis. In recent years, knowledge about this orphan group of diseases increased substantially among clinicians. However, the difficult task of integrating clinical symptoms and laboratory values still leads to a critical delay in diagnosis and therapy for patients. This review aims at enhancing the understanding of neurotransmitter disorders and should help practicing clinicians to choose useful diagnostic steps on the way to a valid diagnosis.

The inhibitor of nuclear factor kappa B zeta (IκBζ) is an atypical member of the IκB protein family. Its function in regulating the activity of the transcription factor nuclear factor kappa B (NFκB) as well as its involvement in cancer-associated processes is poorly understood. In glioma patients, enhanced expression of IκBζ in tumor specimen is associated with poor prognosis. Here we report that IκBζ is upregulated in a glioma cell line resistant towards NFκB-dependent non-apoptotic cell death. Upon γ-irradiation of glioma cells, IκBζ expression is enhanced, and subsequently serves as a transcriptional activator of the tumor promoting cytokines interleukin (IL-6), IL-8 and chemokine (C-X-C motif) ligand 1 (CXCL1) that are known to be involved in glioma associated inflammatory processes. In contrast, shRNA-mediated knockdown of IκBζ reduces the expression of the aforementioned cytokines. We propose a previously unappreciated role of IκBζ in the inflammatory micromilieu as well as progression in glioma.

Recent studies have demonstrated that histone deacetylase (HDAC) inhibitors (HDACi) have potential immunomodulatory activity since they affect the immune surveillance by regulating the production of cytokines, alter the activity and function of macrophages and dendritic cells (DC), regulate the transcription of a variety of immune-stimulating genes, and can modulate the activity of immune effector cells of both the innate and adaptive immune system. Besides their immunostimulatory activity, HDACi can induce growth arrest and cell death, and modulate a subset of cellular functions such as cell motility or differentiation. This makes HDACi interesting therapeutic candidates for the treatment of a variety of human diseases like cancer, autoimmune, and graft versus host diseases. Besides these, HDACs have been shown to be involved in virus replication and pathogenesis, and it was recently shown that HDACi provide therapeutic effects in the treatment of oncogenic virus infections and associated malignancies. This review will further give information about the different families of HDACs and their opponents, the histone acetylases (HATs), about the classes and function of specific HDACi, and their use in the treatment of human diseases.