Genetic Phenomena Commons^™

The Effect Of Tert Promoter Mutation On Predicting Meningioma Outcomes: A Multi-Institutional Cohort Analysis, Karenna J Groff, Ruchit V Patel, Yang Feng, Hia S Ghosh, Miguel A Millares Chavez, Joseph O'Brien, William C Chen, Vijay Nitturi, Akshay V Save, Mark W Youngblood, Craig M Horbinski, James P Chandler, Felix Ehret, Chloe Gui, Justin Z Wang, Kristen Park, Sonia Ajmera, Marc Rosenblum, Abigail K Suwala, Catena Kresbach, Christopher W Mount, Ulrich Schüller, Sandro Santagata, Felix Sahm, Tejus A Bale, Christina Jackson, Timothy E Richardson, Chunyu Cai, Farshad Nassiri, Gelareh Zadeh, David Kaul, David Capper, Stephen T Magill, John G Golfinos, Chandra Sen, Akash J Patel, David R Raleigh, Jennifer Moliterno, Donato Pacione, Matija Snuderl, Wenya Linda Bi

Duncan NRI Faculty and Staff Publications

Background: Molecular aberrations have been incorporated into tumour classification guidelines of meningioma. TERT-promoter (TERTp) mutation is associated with worse prognosis and is designated a WHO grade 3 biomarker. However, it remains unclear whether TERTp mutation is context-dependent, with other co-occurring genetic alterations potentially driving its association with prognosis. We sought to characterise the role of TERTp mutation in meningioma and guide TERTp sequencing.

Methods: We identified 1492 patients of all ages who had previously received surgery for meningioma across 14 medical centres in the USA, Canada, and Germany. Patients were eligible if they had post-surgical clinical or radiographical assessment of …

Plasma Lipidome Dysregulation In Frontotemporal Dementia Reveals Shared, Genotype-Specific, And Severity-Linked Alterations., Yohannes A Ambaw, Peter A Ljubenkov, Shubham Singh, Abdi Hamed, Sebastian Boland, Adam L Boxer, Tobias C Walther, Robert V Farese

Duncan NRI Faculty and Staff Publications

Introduction: Biomarkers are essential for monitoring the progression of frontotemporal dementia (FTD). Although dysregulated brain lipid metabolism, particularly sphingolipids enriched in the nervous system, is a key feature of neurodegeneration, plasma lipids remain underexplored as biomarkers compared to imaging and serum proteins.

Methods: We examined plasma lipidomes using liquid chromatography-tandem mass spectrometry (LC-MS/MS) from individuals carrying pathogenic variants linked to autosomal dominant FTD (GRN, C9orf72, MAPT) and non-carriers.

Results: FTD subjects exhibited increased plasma levels of gangliosides (GM3(d18:1_16:0), GM3(d18:1_24:1)), ceramide Cer(d18:1_23:0), and select polyunsaturated triacylglycerols. In contrast, phosphatidylethanolamine (PE(18:0_24:0) and sphingomyelin (SM(38:0) were reduced. Subtype-specific changes included elevated glucosylsphingosine (GlcSph(d18:1) …

A Protective Role Of Src-1 Against Aging Associated Cognitive Decline, Hesong Liu, Yongjie Yang, Jonathan C Bean, Yang He, Hailan Liu, Rambabu Majji, Chen Liang, Nan Zhang, Meng Yu, Longlong Tu, Qingzhuo Liu, Yue Deng, Kristine M Conde, Na Yin, Mengjie Wang, Yongxiang Li, Junying Han, Sanika Vattakuzhiyil Jossy, Megan Elyse Burt, Hari Krishna Yalamanchili, Chunmei Wang

Duncan NRI Faculty and Staff Publications

Introduction: Research indicates a strong correlation between obesity and the risk of dementia, both are linked to steroid receptor coactivator-1 (SRC-1), a transcriptional coactivator.

Methods: We used RNA sequencing analysis (RNA-Seq) to investigate the transcriptome of SRC-1-KO mice, and identified S100 calcium-binding protein A6 (S100A6), an AD associated gene, as one target of SRC-1. We tested cognitive behaviors in SRC-1-KO mice and mice with a humanized SRC-1 mutation (SRC-1L1376P), and performed promoter luciferase assays on S100A6.

Results: Loss of SRC-1 caused alterations in gene signatures that are commonly associated with neurodegenerative diseases, including AD, and diminished the neural plasticity of …

Heterozygous Variants In Plcg1 Affect Hearing, Vision, Cardiac, And Immune Function, Mengqi Ma, Yiming Zheng, Mingxi Deng, Shenzhao Lu, Xueyang Pan, Xi Luo, Michelle Etoundi, David Li-Kroeger, Kim C Worley, Lindsay C Burrage, Lauren S Blieden, Aimee Allworth, Wei-Liang Chen, Giuseppe Merla, Barbara Mandriani, Catherine E Otten, Pierre Blanc, Jill A Rosenfeld, Debdeep Dutta, Shinya Yamamoto, Michael F Wangler, Ian A Glass, Jingheng Chen, Elizabeth Blue, Paolo Prontera, Jeremie Rosain, Sandrine Marlin, Seema R Lalani, Hugo J Bellen, Undiagnosed Diseases Network

Duncan NRI Faculty and Staff Publications

Phospholipase C isozymes (PLCs) hydrolyze phosphatidylinositol 4,5-bisphosphate (PIP₂) into inositol 1,4,5-trisphosphate (IP₃) and diacylglycerol (DAG), important signaling molecules involved in many cellular processes including Ca²⁺ release from the endoplasmic reticulum (ER). PLCG1 encodes the PLCγ1 isozyme that is broadly expressed. Hyperactive somatic mutations of PLCG1 are observed in multiple cancers, but only one germline variant has been reported. Here, we describe seven individuals with heterozygous missense variants in PLCG1 [p.(Asp1019Gly), p.(His380Arg), p.(Asp1165Gly), and p.(Leu597Phe)] who present with hearing impairment (5/7), ocular pathology (4/7), cardiac septal defects (3/6), and various immunological issues (5/7). To model these …

Current Practices In The Study Of Biomolecular Acondensates: A Community Comment, Simon Alberti, Paolo Arosio, Robert B Best, Steven Boeynaems, Danfeng Cai, Rosana Collepardo-Guevara, Gregory L Dignon, Rumiana Dimova, Shana Elbaum-Garfinkle, Nicolas L Fawzi, Monika Fuxreiter, Amy S Gladfelter, Alf Honigmann, Ankur Jain, Jerelle A Joseph, Tuomas P J Knowles, Keren Lasker, Edward A Lemke, Kresten Lindorff-Larsen, Reinhard Lipowsky, Jeetain Mittal, Samrat Mukhopadhyay, Sua Myong, Rohit V Pappu, Karsten Rippe, Tatyana A Shelkovnikova, Anthony G Vecchiarelli, Susanne Wegmann, Huaiying Zhang, Mingjie Zhang, Chloe Zubieta, Markus Zweckstetter, Dorothee Dormann, Tanja Mittag

Duncan NRI Faculty and Staff Publications

The realization that the cell is abundantly compartmentalized into biomolecular condensates has opened new opportunities for understanding the physics and chemistry underlying many cellular processes, fundamentally changing the study of biology. The term biomolecular condensate refers to non-stoichiometric assemblies that are composed of multiple types of macromolecules in cells, occur through phase transitions, and can be investigated by using concepts from soft matter physics. As such, they are intimately related to aqueous two-phase systems and water-in-water emulsions. Condensates possess tunable emergent properties such as interfaces, interfacial tension, viscoelasticity, network structure, dielectric permittivity, and sometimes interphase pH gradients and electric potentials–. …

Rare Variants In Bmal1 Are Associated With A Neurodevelopmental Syndrome, Vishnu Anand Cuddapah, Dechun Chen, Bumsik Cho, Rebecca Moore, Mohnish Suri, Hana Safraou, Frederic Tran-Mau-Them, Ashley Wilson, Jacqueline Odgis, Atteeq U Rehman, Carol Saunders, Shiva Ganesan, Vaidehi Jobanputra, Stephen W Scherer, Ingo Helbig, Amita Sehgal

Duncan NRI Faculty and Staff Publications

Children with neurodevelopmental disorders exhibit highly penetrant sleep and circadian dysfunction, but the underlying mechanisms are unclear. We asked whether a subset of individuals with neurodevelopmental disorders might have genetic variants in genes known to drive circadian rhythms. Through international collaboration, we identified ten individuals with very rare genetic variants in BMAL1, a core component of the molecular clock. These individuals exhibited overlapping signs and symptoms including developmental delay, autism spectrum disorder, and variably penetrant marfanoid features. We functionally tested the identified BMAL1 variants in cell culture and in vivo and found disrupted BMAL1 function. These findings demonstrate that …

Bridging Psychiatry And Rare Genetic Diseases: A Scoping Review Of Therapeutic Strategies And Diagnostic Delay Paired With Healthcare Economic Burden Analysis, Sheldon R Garrison, Isaac J Siegel, Christopher R Takala, Sarah L Vaithilingam, Gene W Yang, Anthony W Zoghbi, Madeline M Hartig, Sreya Vadapalli, Margaret E Anderson

Duncan NRI Faculty and Staff Publications

Rare genetic diseases (RDs) with primary neuropsychiatric symptoms pose unique challenges for diagnosis and management. While the majority of these RDs have neuropsychiatric symptoms that are secondary to the RD, a subset presents with primary neuropsychiatric symptoms directly linked to their underlying pathophysiology. This subset has significant unmet medical need with delayed diagnoses leading to prolonged delays in treatment optimization and the trialing of medications that fail to target the underlying pathophysiology. This comprehensive review identifies 108 RDs with central neuropsychiatric symptoms that have a 7.7-year average diagnostic delay. Optimal management strategies for these RDs typically includes non-psychotropic medications, dietary …

Rapid Dissection And Dissociation Of The Mouse Olfactory Epithelium For Single-Nucleus Suspensions, Benjamin D W Belfort, Anthony M Insalaco, Claude C Chew, Johnathan D Jia, Julia Younis, Benjamin R Arenkiel

Duncan NRI Faculty and Staff Publications

The murine olfactory epithelium is the initial entry point of the olfactory system, housing various cell types that include olfactory sensory neurons, their regenerating progenitors, and support cells. Olfactory sensory neurons transduce chemical odorants into neural signals, yet the mechanisms underlying how these cells develop and turnover, create synapses with the olfactory bulb, and regulate their odorant receptors remain areas of intense study. Located on the dorsal aspect of the nasal cavity, the olfactory epithelium adheres to intricate bony structures known as turbinates. This anatomy poses unique challenges for its extraction and dissociation, especially in the context of preparing viable …

De Novo And Inherited Variants In Ddx39b Cause A Novel Neurodevelopmental Syndrome, Kevin T A Booth, Sharayu V Jangam, Martin M C Chui, Kayla Treat, Lorenzo Graziani, Alessia Soldano, Yao Ruan, Jeffrey Wan-Hei Hui, Kerry White, Celanie K Christensen, Ty Lynnes, Shinya Yamamoto, Oguz Kanca, Mandy H Y Tsang, Sally A Lynch, Sureni V Mullegama, Julia Baptista, Daniela Iancu, Shelagh K Joss, Sandra Y Y Wong, Christopher C Y Mak, Anna K Y Kwong, Hugo J Bellen, Erin Conboy, Remo Sanges, Anskar Yu-Hung Leung, Michael F Wangler, Brian H Y Chung, Francesco Vetrini

Duncan NRI Faculty and Staff Publications

DDX39B is a conserved member of the DEAD-box family of ATP-dependent RNA helicases, critical in mRNA metabolism across eukaryotes. DDX39B is also a core component of the TRanscription-EXport (TREX) super protein complex, and recent studies have highlighted the important role of its subunits in neurodevelopmental disorders. Here, we describe six individuals from five families, four harbouring de novo missense variants in DDX39B and one with an inherited splicing variant, presenting with variable developmental delay, congenital hypotonia, epilepsy, short stature, skeletal abnormalities, dysmorphic features and microcephaly in three patients.

3D molecular modelling predicts these variants would alter protein structure. In vitro …

Folliculin Depletion Results In Liver Cell Damage And Cholangiocarcinoma Through Mit/Tfe Activation, Bruno Maria Custode, Francesco Annunziata, Felipe Dos Santos Matos, Valentina Schiano, Veronica Maffia, Milena Lillo, Rita Colonna, Rossella De Cegli, Andrea Ballabio, Nunzia Pastore

Duncan NRI Faculty and Staff Publications

Mutations in the tumor suppressor gene Folliculin (FLCN) are responsible for Birt-Hogg-Dube’ (BHD) syndrome, a rare inherited condition that predisposes affected individuals to skin tumors, pulmonary cysts, and kidney tumors. FLCN regulates key cellular pathways, including TFEB, TFE3, and mTORC1, which are critical for maintaining cell homeostasis. Loss of FLCN leads to both hyperactivation of mTORC1 and constitutive activation of TFEB and TFE3, contributing to tumorigenesis. While previous studies showed that Flcn liver-specific conditional knockout (FlcnLiKO) mice are protected from developing liver fibrosis and damage upon high-fat diet exposure, the potential role of FLCN loss in liver carcinogenesis …

Cell Type-Specific Purifying Selection Of Synonymous Mitochondrial Dna Variation, Caleb A Lareau, Patrick Maschmeyer, Yajie Yin, Jacob C Gutierrez, Ryan S Dhindsa, Anne-Sophie Gribling-Burrer, Sebastian Zielinski, Yu-Hsin Hsieh, Lena Nitsch, Veronika Dimitrova, Benan Nalbant, Frank A Buquicchio, Tsion Abay, Robert R Stickels, Jacob C Ulirsch, Patrick Yan, Fangyi Wang, Zhuang Miao, Katalin Sandor, Bence Daniel, Vincent Liu, Paul L Mendez, Petra Knaus, Manpreet Meyer, William J Greenleaf, Anshul Kundaje, Redmond P Smyth, Mathias Munschauer, Leif S Ludwig, Ansuman T Satpathy

Duncan NRI Faculty and Staff Publications

While somatic variants are well-characterized drivers of tumor evolution, their influence on cellular fitness in nonmalignant contexts remains understudied. We identified a mosaic synonymous variant (m.7076A > G) in the mitochondrial DNA (mtDNA)-encoded cytochrome c-oxidase subunit 1 (MT-CO1, p.Gly391=), present at homoplasmy in 47% of immune cells from a healthy donor. Single-cell multiomics revealed strong, lineage-specific selection against the m.7076G allele in CD8+ effector memory T cells, but not other T cell subsets, mirroring patterns of purifying selection of pathogenic mtDNA alleles. The limited anticodon diversity of mitochondrial tRNAs forces m.7076G translation to rely on wobble pairing, unlike the Watson-Crick-Franklin pairing …

Sleep Drive, Not Total Sleep Amount, Increases Seizure Risk, Vishnu Anand Cuddapah, Cynthia T Hsu, Fernanda Valle Sirias, Yongjun Li, Hrishit M Shah, Christopher Saul, Samantha Killiany, Camilo Guevara, Joy Shon, Zhifeng Yue, Gabrielle L Gionet, Mary E Putt, Amita Sehgal

Duncan NRI Faculty and Staff Publications

Sleep loss has been associated with increased seizure risk since antiquity. Using automated video detection of spontaneous seizures in Drosophila epilepsy models, we show that seizures worsen only when sleep restriction raises homeostatic "sleep drive," not simply when total sleep amount falls. This is supported by the paradoxical finding that acute activation of sleep-promoting circuits worsens seizures, because it increases sleep drive without changing sleep amount. Sleep-promoting circuits become hyperactive after sleep loss and are associated with increased whole-brain activity. During sleep restriction, optogenetic inhibition of sleep-promoting circuits to reduce sleep drive protects against seizures. Downregulation of the 5HT1A serotonin …

C-Terminal Frameshift Variants In Gpkow Are Associated With A Multisystemic X-Linked Disorder, Jung-Wan Mok, Laura Mackay, Maria Blazo, Elizabeth Mizerik, Jozef Gecz, Renee Carroll, Mathilde Nizon, Sophie Rondeau, Madeleine Joubert, Silvestre Cuinat, Wallid Deb, Fernanda Valle Sirias, Monika Weisz-Hubshman, Shamika Ketkar, Urszula Polak, Alyssa A Tran, Debra Kearney, Neil A Hanchard, Oguz Kanca, Michael F Wangler, Hugo J Bellen, Brendan H Lee, Shinya Yamamoto, Keren Machol

Duncan NRI Faculty and Staff Publications

Purpose: GPKOW, a gene on the X-chromosome, encodes a nuclear RNA-binding protein important in messenger RNA (mRNA) processing as a spliceosome subunit. This work aims to establish GPKOW as a disease-associated gene.

Methods: We describe 3 males from 2 unrelated families with hemizygous frameshift variants affecting the last exon of GPKOW p.(Arg441SerfsTer30) and p.(Ser444GlufsTer28). The effect of p.(Ser444GlufsTer28) on gene expression was evaluated in patient's fibroblasts. In vivo studies in Drosophila melanogaster targeting the sole GPKOW fly ortholog, CG10324 (Gpkow) were performed.

Results: Clinical presentations included intrauterine growth restriction, microcephaly/microencephaly, and eye, brain, skin, and skeletal abnormalities. Heterozygote females presented …

Distinguishing Pex2 And Pex16 Gene Variant Severity For Mild, Severe And Atypical Peroxisome Biogenesis Disorders, Vanessa A Gomez, Oguz Kanca, Sharayu V Jangam, Saurabh Srivastav, Jonathan C Andrews, Michael F Wangler

Duncan NRI Faculty and Staff Publications

Peroxisomal biogenesis disorders (PBD) are autosomal recessive diseases caused by mutations in specific PEX genes that impair peroxisome formation, leading to multi-systemic failure. Symptoms vary, even in patients with variants in the same PEX gene. Our goal is to select PEX mutations and use Drosophila to model a severity spectrum based on genotype-phenotype correlations. Utilizing KozakGAL4 (KZ) cassettes, we replaced the coding sequence of Pex with a GAL4 driver, ideal for making 'humanized' flies in which human PEX can replace the fly loss. We generated Pex2KZ and Pex16KZ lines and assessed them in various behavior assays, confirming their severe phenotypes. …

Nf2 Loss-Of-Function And Hypoxia Drive Radiation Resistance In Grade 2 Meningiomas, Bhuvic Patel, Sangami Pugazenthi, Collin W English, Vijay Nitturi, Shree S Pari, Tatenda Mahlokozera, William A Leidig, Hsiang-Chih Lu, Alicia Yang, Kaleigh Roberts, Patrick Desouza, Kyle P Mcgeehan, Diane D Mao, Namita Sinha, Joseph E Ippolito, Sonika Dahiya, Allegra Petti, Hiroko Yano, Tiemo J Klisch, Akdes S Harmanci, Akash J Patel, Albert H Kim

Duncan NRI Faculty and Staff Publications

Background: World Health Organization Grade 2 meningiomas (G2Ms) often recur and resist therapies. Grade 2 meningiomas with histopathological necrosis have been associated with worse local control (LC) after radiation therapy, but the drivers and biomarkers of radiation resistance in G2Ms remain unknown.

Methods: We performed genetic sequencing and histopathological analysis of 113 G2Ms and investigated the role of genetic and microenvironmental factors on clonogenic survival after ionizing radiation. We performed transcriptional profiling of our in vitro model and 18 human G2M tumors by bulk RNA sequencing as well as 8 G2Ms by single nuclei RNA sequencing.

Results: NF2 loss-of-function (LOF) …

Time To Treatment In Pediatric Patients With Repeated Episodes Of Status Epilepticus, Jennifer V Gettings, Iván Sánchez Fernández, Anne Anderson, J Nicholas Brenton, Afra Can, Justice Clark, Raquel Farias Moeller, Howard P Goodkin, Yi-Chen Lai, Mohamad A Mikati, Lindsey A Morgan, Edward Novotny, Adam P Ostendorf, Juan Piantino, James J Riviello, Kumar Sannagowdara, Robert C Tasker, Dmitry Tchapyjnikov, Mark S Wainwright, Angus Wilfong, Korwyn Williams, Bo Zhang, Tobias Loddenkemper, Marina Gaínza-Lein, Pediatric Status Epilepticus Research Group (Pserg)

Duncan NRI Faculty and Staff Publications

Objective: To compare pediatric patients who presented with repeated status epilepticus episodes to patients with a single episode of status epilepticus and identify distinguishing clinical factors.

Methods: Retrospective analysis of a multicenter, prospective observational cohort of pediatric patients with status epilepticus between 2011 and 2019.

Results: Out of 504 status epilepticus episodes in 420 patients, 50 patients (10.3%) had repeated episodes of status epilepticus. The only predictor of repeated status epilepticus was a prior diagnosis of epilepsy. There was no difference in time to treatment with the first benzodiazepine in patients presenting with their first status epilepticus episode compared to …

The Cgas/Sting Pathway: Friend Or Foe In Regulating Cardiomyopathy, Weiyue Wang, Yuanxu Gao, Hyun Kyoung Lee, Albert Cheung-Hoi Yu, Markus Kipp, Hannes Kaddatz, Jiangshan Zhan

Duncan NRI Faculty and Staff Publications

Inflammation is a central hallmark of cardiomyopathy, where misdirected immune responses contribute to chronic myocardial dysfunction. Among the emerging molecular mechanisms implicated in this process, the cyclic GMP-AMP synthase (cGAS)/stimulator of interferon genes (STING) signaling pathway has garnered increasing attention. Acting as a key cytosolic DNA sensor, the cGAS/STING pathway orchestrates inflammatory responses triggered by microbial infections or endogenous cellular stressors such as autophagy and apoptosis. Despite its pivotal role, the precise molecular mechanisms regulating this pathway and its role in cardiomyopathy-associated inflammation remain poorly understood and subject to ongoing debate. To address this scientific gap, we first reviewed key …

Alzheimer’S Disease Protective Allele Of Clusterin Modulates Neuronal Excitability Through Lipid-Droplet-Mediated Neuron-Glia Communication, Xiaojie Zhao, Yan Li, Siwei Zhang, Ari Sudwarts, Hanwen Zhang, Alena Kozlova, Matthew J Moulton, Lindsey D Goodman, Zhiping P Pang, Alan R Sanders, Hugo J Bellen, Gopal Thinakaran, Jubao Duan

Duncan NRI Faculty and Staff Publications

Background: Genome-wide association studies (GWAS) of Alzheimer's disease (AD) have identified a plethora of risk loci. However, the disease variants/genes and the underlying mechanisms have not been extensively studied.

Methods: Bulk ATAC-seq was performed in induced pluripotent stem cells (iPSCs) differentiated various brain cell types to identify allele-specific open chromatin (ASoC) SNPs. CRISPR-Cas9 editing generated isogenic pairs, which were then differentiated into glutamatergic neurons (iGlut). Transcriptomic analysis and functional studies of iGlut co-cultured with mouse astrocytes assessed neuronal excitability and lipid droplet formation.

Results: We identified a putative causal SNP of CLU that impacted neuronal chromatin accessibility to transcription-factor(s), with …

New Insights Into Epileptic Spasm Generation And Treatment From The Ttx Animal Model, John W Swann, Carlos J Ballester-Rosado, Chih-Hong Lee

Duncan NRI Faculty and Staff Publications

Currently, we have an incomplete understanding of the mechanisms underlying infantile epileptic spasms syndrome (IESS). However, over the past decade, significant efforts have been made to develop IESS animal models to provide much-needed mechanistic information for therapy development. Our laboratory has focused on the TTX model and in this paper, we review some of our findings. To induce spasms, tetrodotoxin (TTX) is infused into the neocortex of infant rats. TTX produces a lesion at its infusion site and thus mimics IESS resulting from acquired structural brain abnormalities. Subsequent electrophysiological studies showed that the epileptic spasms originate from neocortical layer V …

Volumetric Changes In Cerebellar Transverse Zones: Age And Sex Effects In Health And Neurological Disorders, Farshid Ghiyamihoor, Payam Paymani, Jarrad Perron, Azam Asemi-Rad, Mehdi Marzban, Aashka Mohite, Karen Ardila, Bara Aljada, Asghar Marzban, Mehnosh Toback, Sherif Eltonsy, Ji Hyun Ko, Tabrez J Siddiqui, Christopher J Steele, Jiming Kong, Mario Manto, M Ethan Macdonald, Jason S Gill, Roy V Sillitoe, Fuat Balcı, Iman Beheshti, Hassan Marzban

Duncan NRI Faculty and Staff Publications

Cerebellar volumetric changes are intricately linked to aging, with distinct patterns across its transverse zones, the functional subdivisions characterized by unique cytoarchitectural and connectivity profiles. Despite research efforts, the cerebellar aging process in health and neurological disorders remains poorly understood. In this study, we investigated the effects of age and sex on total cerebellum, transverse zone, and lobule volumes using MRI data from over 45,000 participants compiled from six neuroimaging datasets. We also propose a framework for estimating cerebellum age as an indicator of cerebellar health. Significant age‐dependent volume reductions were observed across transverse zones, with the …

An Open-Label Study Evaluating The Safety And Efficacy Of Amo-01 For The Treatment Of Seizures In Phelan-Mcdermid Syndrome, Tess Levy, J Lloyd Holder, Joseph P Horrigan, Michael F Snape, Alison Mcmorn, Christina Layton, Hailey Silver, Kate Friedman, Hannah Grosman, Slayton Underwood, Danielle Halpern, Jessica Zweifach, Paige M Siper, Alexander Kolevzon

Duncan NRI Faculty and Staff Publications

Phelan-McDermid syndrome (PMS) is a neurodevelopmental disorder caused by haploinsufficiency of the SHANK3 gene. Approximately 25% of individuals with PMS have epilepsy. Treatment of epilepsy in PMS may require multiple anticonvulsants, and in a minority of cases, seizures remain poorly controlled. Converging lines of evidence in different experimental models indicate that the Ras-ERK pathway is implicated in the pathophysiology of seizure generation and neurobehavioral symptoms in PMS. The goal of this study was to evaluate the safety, tolerability, and efficacy in treating seizures in adults and adolescents with PMS using AMO-01, a Ras-ERK pathway inhibitor. A single 6-hour intravenous infusion …

Life On The Dry Side: A Roadmap To Understanding Desiccation Tolerance And Accelerating Translational Applications, R A Marks, J T B Ekwealor, M A S Artur, L Bondi, T C Boothby, O M S Carmo, D C Centeno, K K Coe, H J W Dace, S Field, A Hutt, S Porembski, A Thalhammer, L Van Der Pas, A J Wood, P Alpert, D Bartels, S Boeynaems, M N Datar, T Giese, W I Seidou, S M Kirchner, J Köhler, U G V S S Kumara, J Kyung, R Lyall, B D Mishler, J B V T Ndongmo, M S Otegui, V Reddy, J Rexroth, S M Tebele, R Vanburen, J Verdier, U C Vothknecht, M F Wittenberg, E Zokov, M J Oliver, S Y Rhee

Duncan NRI Faculty and Staff Publications

To thrive in extreme conditions, organisms have evolved a diverse arsenal of adaptations that confer resilience. These species, their traits, and the mechanisms underlying them comprise a valuable resource that can be mined for numerous conceptual insights and applied objectives. One of the most dramatic adaptations to water limitation is desiccation tolerance. Understanding the mechanisms underlying desiccation tolerance has important potential implications for medicine, biotechnology, agriculture, and conservation. However, progress has been hindered by a lack of standardization across sub-disciplines, complicating the integration of data and slowing the translation of basic discoveries into practical applications. Here, we synthesize current knowledge …

De Novo Variants In Cdkl1 And Cdkl2 Are Associated With Neurodevelopmental Symptoms, Ali H Bereshneh, Jonathan C Andrews, Daniel F Eberl, Guney Bademci, Nicholas A Borja, Stephanie Bivona, Wendy K Chung, Shinya Yamamoto, Michael F Wangler, Shane Mckee, Mustafa Tekin, Hugo J Bellen, Oguz Kanca

Duncan NRI Faculty and Staff Publications

The CDKL (cyclin-dependent kinase-like) family consists of five members in humans, CDKL1-5, that encode serine-threonine kinases. The only member that has been associated with a Mendelian disorder is CDKL5, and variants in CDKL5 cause developmental and epileptic encephalopathy type 2 (DEE2). Here, we study four de novo variants in CDKL2 identified in five individuals, including three unrelated probands and monozygotic twins. These individuals present with overlapping symptoms, including global developmental delay, intellectual disability, childhood-onset epilepsy, dyspraxia, and speech deficits. We also identified two individuals with de novo missense variants in CDKL1 in the published Deciphering Developmental Disorders (DDD) and GeneDx …

Breaking The Synaptic Vesicle Cycle: Mechanistic Insights Into Presynaptic Dysfunctions In Epilepsy, Kevin Jiang, Lu-Tang Yang, Mingshan Xue

Duncan NRI Faculty and Staff Publications

Synaptic dysfunction is a hallmark of many neurological disorders including epilepsy. An increasing number of epilepsy-causing pathogenic variants are being identified in genes encoding presynaptic proteins that affect every step of the synaptic vesicle cycle, from vesicle loading, tethering, docking, priming, calcium sensing, fusing, to recycling. These different molecular dysfunctions result in converging impairment of presynaptic neurotransmitter release, yet lead to diverse epileptic disorders. This review focuses on representative monogenic epileptic disorders caused by pathogenic variants of key presynaptic proteins involved in different stages of the synaptic vesicle cycle: SYN1 (vesicle pool regulation), STXBP1 (vesicle docking, priming, and fusion), and …

Glucose Uptake In Pigment Glia Suppresses Tau-Induced Inflammation And Photoreceptor Degeneration, Mikiko Oka, Sho Nakajima, Emiko Suzuki, Shinya Yamamoto, Kanae Ando

Duncan NRI Faculty and Staff Publications

Brain inflammation contributes to the pathogenesis of neurodegenerative diseases, such as Alzheimer's disease (AD). Glucose hypometabolism and glial activation are pathological features seen in AD brains; however, the connection between the two is not fully understood. Using a Drosophila model of AD, we identified that glucose metabolism in glia plays a critical role in neuroinflammation under disease conditions. Expression of human MATP (hereafter referred to as Tau) in the retinal cells, including photoreceptor neurons and pigment glia, causes photoreceptor degeneration accompanied by the formation of dark-stained round inclusion-like structures and swelling of the lamina cortex. We found that inclusion-like structures …

De Novo Variants In Rybp Are Associated With A Severe Neurodevelopmental Disorder And Congenital Anomalies, Monika Weisz-Hubshman, Lindsay C Burrage, Sharayu V Jangam, Jill A Rosenfeld, Sandra Von Hardenberg, Anke Bergmann, Manuela Friederike Richter, Malgorzata Rydzanicz, Rafal Ploski, Agnieszka Stembalska, Wendy K Chung, Rebecca R Hernan, Foong Y Lim, Theresa Brunet, Steffen Syrbe, Boris Keren, Solveig Heide, David R Murdock, Hongzheng Dai, Fan Xia, Shamika Ketkar, Brian Dawson, Vinodh Narayanan, Hillary K Graves, Undiagnosed Diseases Network, Michael F Wangler, Carlos Bacino, Brendan Lee

Duncan NRI Faculty and Staff Publications

Purpose: Polycomb group proteins are key epigenetic transcriptional regulators. Multiple neurodevelopmental disorders are associated with pathogenic variants of the genes encoding Polycomb group proteins. RYBP is a core component of the noncanonical Polycomb Repressor Complex 1; however, its role in disease is unclear.

Methods: Functional consequences of RYBP variants were assessed using in vitro cellular and in vivo Drosophila melanogaster studies.

Results: We described 7 individuals with heterozygous de novo variants of RYBP and their clinical findings, including severe developmental delay, dysmorphisms, and multiple congenital anomalies. We showed that all single-nucleotide variants in RYBP localize to the N-terminal domain of …

Staged Screening Identifies People With Biomarkers Related To Neuronal Alpha-Synuclein Disease, Ethan G Brown, Lana M Chahine, Andrew Siderowf, Caroline Gochanour, Ryan Kurth, Micah J Marshall, Chelsea Caspell-Garcia, Michael C Brumm, Craig E Stanley, Monica Korell, Bridget Mcmahon, Maggie Kuhl, Kimberly Fabrizio, Laura Heathers, Luis Concha-Marambio, Claudio Soto, Sohini Chowdhury, Christopher S Coffey, Tatiana M Foroud, Tanya Simuni, Kenneth Marek, Caroline M Tanner

Faculty, Staff and Student Publications

Objective: Remote identification of individuals with severe hyposmia may enable scalable recruitment of participants with underlying alpha-synuclein aggregation. We evaluated the performance of a staged screening paradigm using remote smell testing to enrich for abnormal dopamine transporter single-photon emission computed tomography imaging (DAT-SPECT) and alpha-synuclein aggregation.

Methods: The Parkinson's Progression Markers Initiative (PPMI) recruited participants for the prodromal cohort who were 60-years and older without a Parkinson's disease diagnosis. Participants were invited to complete a University of Pennsylvania Smell Identification Test (UPSIT) independently through an online portal. Hyposmic participants were invited to complete DAT-SPECT, which determined eligibility for enrollment in …

Distinct Patterns Of Pv And Sst Gabaergic Neuronal Activity In The Basal Forebrain During Olfactory-Guided Behavior In Mice, Elizabeth H Moss, Evelyne K Tantry, Elaine Le, Pey-Shyuan Chin, Priscilla Ambrosi, Katie L Brandel-Ankrapp, Benjamin R Arenkiel

Duncan NRI Faculty and Staff Publications

Sensory perception relies on the flexible detection and interpretation of stimuli across variable contexts, conditions, and behavioral states. The basal forebrain (BF) is a hub for behavioral state regulation, supplying dense cholinergic and GABAergic projections to various brain regions involved in sensory processing. Of GABAergic neurons in the BF, parvalbumin (PV) and somatostatin (SST) subtypes serve opposing roles toward regulating behavioral states. To elucidate the role of BF circuits in sensory-guided behavior, we investigated GABAergic signaling dynamics during odor-guided decision-making in male and female mice. We used fiber photometry to record cell type-specific BF activity during an odor discrimination task …

Protocol For Unlocking Alternative Polyadenylation Insights From Bulk Rna-Seq Data With Polyaminer-Bulk, Venkata Jonnakuti, Sriya Jonnakuti, Hari Krishna Yalamanchili

Duncan NRI Faculty and Staff Publications

PolyAMiner-Bulk, a deep-learning-based algorithm to decode alternative polyadenylation (APA) dynamics from bulk RNA sequencing (RNA-seq) data, enables scientists to identify and quantify APA events from processed bulk RNA-seq data. The protocol allows researchers to explore differential APA usage between two conditions and gain a better understanding of post-transcriptional regulatory mechanisms. The major steps involve input data preparation, executing PolyAMiner-Bulk, and interpreting the results. A basic familiarity with pre-processing bulk RNA-seq data and command-line tools is suggested.

For complete details on the use and execution of this protocol, please refer to Jonnakuti et al.¹

Diverse Ancestral Representation Improves Genetic Intolerance Metrics, Alexander L Han, Chloe F Sands, Dorota Matelska, Jessica C Butts, Vida Ravanmehr, Fengyuan Hu, Esmeralda Villavicencio Gonzalez, Nicholas Katsanis, Carlos D Bustamante, Quanli Wang, Slavé Petrovski, Dimitrios Vitsios, Ryan S Dhindsa

Duncan NRI Faculty and Staff Publications

The unprecedented scale of genomic databases has revolutionized our ability to identify regions in the human genome intolerant to variation—regions often implicated in disease. However, these datasets remain constrained by limited ancestral diversity. Here, we analyze whole-exome sequencing data from 460,551 UK Biobank and 125,748 Genome Aggregation Database (gnomAD) participants across multiple ancestries to test several key intolerance metrics, including the Residual Variance Intolerance Score (RVIS), Missense Tolerance Ratio (MTR), and Loss-of-Function Observed/Expected ratio (LOF O/E). We demonstrate that increasing ancestral representation, rather than sample size alone, critically drives their performance. Scores trained on variation observed in African and Admixed …