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The corpus callosum is a bundle of axon fibres that connects the two hemispheres of the brain. Neurodevelopmental disorders that feature dysgenesis of the corpus callosum as a core phenotype offer a valuable window into pathology derived from abnormal axon development. Here, we describe a cohort of eight patients with a neurodevelopmental disorder characterized by a range of deficits including corpus callosum abnormalities, developmental delay, intellectual disability, epilepsy and autistic features. Each patient harboured a distinct de novo variant in MYCBP2, a gene encoding an atypical really interesting new gene (RING) ubiquitin ligase and signalling hub with evolutionarily conserved functions in axon development. We used CRISPR/Cas9 gene editing to introduce disease-associated variants into conserved residues in the Caenorhabditis elegans MYCBP2 orthologue, RPM-1, and evaluated functional outcomes in vivo. Consistent with variable phenotypes in patients with MYCBP2 variants, C. elegans carrying the corresponding human mutations in rpm-1 displayed axonal and behavioural abnormalities including altered habituation. Furthermore, abnormal axonal accumulation of the autophagy marker LGG-1/LC3 occurred in variants that affect RPM-1 ubiquitin ligase activity. Functional genetic outcomes from anatomical, cell biological and behavioural readouts indicate that MYCBP2 variants are likely to result in loss of function. Collectively, our results from multiple human patients and CRISPR gene editing with an in vivo animal model support a direct link between MYCBP2 and a human neurodevelopmental spectrum disorder that we term, MYCBP2-related developmental delay with corpus callosum defects (MDCD)., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Purpose/objectives: There is a robust body of research on which factors dental schools consider when selecting students for acceptance, but there is considerably less research regarding what factors dental applicants consider when selecting a particular program. The aim of this investigation was to better understand which factors most influenced students to matriculate at a particular dental school and how the value of these factors has changed over time., Methods: To answer this research question, an online survey was utilized to determine why students chose to attend Columbia University College of Dental Medicine (CUCDM). This survey was administered to students in the Class of 2023 and was compared to the responses of an identical survey that was administered to the Class of 2013. The response rate for the classes of 2013 and 2023 were 70.0% and 42.2%, respectively. Results from the Classes of 2013 and 2023 were analyzed using independent sample T-tests., Results: The Class of 2013 ranked academic reputation, location, and admissions into specialty programs as the three most important factors in their selection of a dental school. The Class of 2023 ranked tuition cost, perceived patient pool, and financial aid as their three most important factors., Conclusion(s): For dental schools to continue to successfully attract and enroll students, they must understand what motivates a student to matriculate in a specific dental program. One way to accomplish this is through the use of a survey., (© 2022 American Dental Education Association.)