Biallelic GINS2 variant p.(Arg114Leu) causes Meier-Gorlin syndrome with craniosynostosis

Contains fulltext : 284813.pdf (Publisher’s version ) (Open Access)INTRODUCTION: Replication of the nuclear genome is an essential step for cell division. Pathogenic variants in genes coding for highly conserved components of the DNA replication machinery cause Meier-Gorlin syndrome (MGORS). OBJECTIVE: Identification of novel genes associated with MGORS. METHODS: Exome sequencing was performed to investigate the genotype of an individual presenting with prenatal and postnatal growth restriction, a craniofacial gestalt of MGORS and coronal craniosynostosis. The analysis of the candidate variants employed bioinformatic tools, in silico structural protein analysis and modelling in budding yeast. RESULTS: A novel homozygous missense variant NM_016095.2:c.341G>T, p.(Arg114Leu), in GINS2 was identified. Both non-consanguineous healthy parents carried this variant. Bioinformatic analysis supports its classification as pathogenic. Functional analyses using yeast showed that this variant increases sensitivity to nicotinamide, a compound that interferes with DNA replication processes. The phylogenetically highly conserved residue p.Arg114 localises at the docking site of CDC45 and MCM5 at GINS2. Moreover, the missense change possibly disrupts the effective interaction between the GINS complex and CDC45, which is necessary for the CMG helicase complex (Cdc45/MCM2-7/GINS) to accurately operate. Interestingly, our patient's phenotype is strikingly similar to the phenotype of patients with CDC45-related MGORS, particularly those with craniosynostosis, mild short stature and patellar hypoplasia. CONCLUSION: GINS2 is a new disease-associated gene, expanding the genetic aetiology of MGORS

De Novo variants in EEF2 cause a neurodevelopmental disorder with benign external hydrocephalus

Item does not contain fulltextEukaryotic translation elongation factor 2 (eEF2) is a key regulatory factor in gene expression that catalyzes the elongation stage of translation. A functionally impaired eEF2, due to a heterozygous missense variant in the EEF2 gene, was previously reported in one family with spinocerebellar ataxia-26 (SCA26), an autosomal dominant adult-onset pure cerebellar ataxia. Clinical exome sequencing identified de novo EEF2 variants in three unrelated children presenting with a neurodevelopmental disorder (NDD). Individuals shared a mild phenotype comprising motor delay and relative macrocephaly associated with ventriculomegaly. Populational data and bioinformatic analysis underscored the pathogenicity of all de novo missense variants. The eEF2 yeast model strains demonstrated that patient-derived variants affect cellular growth, sensitivity to translation inhibitors and translational fidelity. Consequently, we propose that pathogenic variants in the EEF2 gene, so far exclusively associated with late-onset SCA26, can cause a broader spectrum of neurologic disorders, including childhood-onset NDDs and benign external hydrocephalus

Human disease genes website series: An international, open and dynamic library for up-to-date clinical information

Since the introduction of next-generation sequencing, an increasing number of disorders have been discovered to have genetic etiology. To address diverse clinical questions and coordinate research activities that arise with the identification of these rare disorders, we developed the Human Disease Genes website series (HDG website series): an international digital library that records detailed information on the clinical phenotype of novel genetic variants in the human genome (https://humandiseasegenes.info/). Each gene website is moderated by a dedicated team of clinicians and researchers, focused on specific genes, and provides up-to-date—including unpublished—clinical information. The HDG website series is expanding rapidly with 424 genes currently adopted by 325 moderators from across the globe. On average, a gene website has detailed phenotypic information of 14.4 patients. There are multiple examples of added value, one being the ARID1B gene website, which was recently utilized in research to collect clinical information of 81 new patients. Additionally, several gene websites have more data available than currently published in the literature. In conclusion, the HDG website series provides an easily accessible, open and up-to-date clinical data resource for patients with pathogenic variants of individual genes. This is a valuable resource not only for clinicians dealing with rare genetic disorders such as developmental delay and autism, but other professionals working in diagnostics and basic research. Since the HDG website series is a dynamic platform, its data also include the phenotype of yet unpublished patients curated by professionals providing higher quality clinical detail to improve management of these rare disorders

De Novo Variants in SPOP Cause Two Clinically Distinct Neurodevelopmental Disorders

Contains fulltext : 217324.pdf (Publisher’s version ) (Closed access

Enhanced performance in fusion plasmas through turbulence suppression by megaelectronvolt ions

© 2022, The Author(s), under exclusive licence to Springer Nature Limited.Alpha particles with energies on the order of megaelectronvolts will be the main source of plasma heating in future magnetic confinement fusion reactors. Instead of heating fuel ions, most of the energy of alpha particles is transferred to electrons in the plasma. Furthermore, alpha particles can also excite Alfvénic instabilities, which were previously considered to be detrimental to the performance of the fusion device. Here we report improved thermal ion confinement in the presence of megaelectronvolts ions and strong fast ion-driven Alfvénic instabilities in recent experiments on the Joint European Torus. Detailed transport analysis of these experiments reveals turbulence suppression through a complex multi-scale mechanism that generates large-scale zonal flows. This holds promise for more economical operation of fusion reactors with dominant alpha particle heating and ultimately cheaper fusion electricity.N