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Zaki-Dizaji M, Abazari MF, Razzaghi H, Shkolnikov I, Christie BR. GRM7 deficiency, from excitotoxicity and neuroinflammation to neurodegeneration: Systematic review of GRM7 deficient patients. Brain Behav Immun Health 2024; 39:100808. [PMID: 38983774 PMCID: PMC11231722 DOI: 10.1016/j.bbih.2024.100808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 06/03/2024] [Accepted: 06/10/2024] [Indexed: 07/11/2024] Open
Abstract
The metabotropic glutamate receptor 7 (mGluR7) is a presynaptic G-protein-coupled glutamate receptor that modulates neurotransmitter release and synaptic plasticity at presynaptic terminals. It is encoded by GRM7, and recently variants have been identified in patients with autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), developmental delay (DD), intellectual disability (ID), and brain malformations. To gain updated insights into the function of GRM7 and the phenotypic spectrum of genetic variations within this gene, we conducted a systematic review of relevant literature utilizing PubMed, Web of Science, and Scopus databases. Among the 14 articles meeting the inclusion criteria, a total of 42 patients (from 28 families) harboring confirmed mutations in the GRM7 gene have been documented. Specifically, there were 17 patients with heterozygous mutations, 20 patients with homozygous mutations, and 5 patients with compound heterozygous mutations. Common clinical features included intellectual behavioral disability, seizure/epilepsy, microcephaly, developmental delay, peripheral hypertonia and hypomyelination. Genotype-phenotype correlation was not clear and each variant had unique characteristics including gene dosage, mutant protein surface expression, and degradation pathway that result with a spectrum of phenotype manifestations through ASD or ADHD to severe DD/ID with brain malformations. Neuroinflammation may play a role in the development and/or progression of GRM7-related neurodegeneration along with excitotoxicity. The clinical and functional data presented here demonstrate that both autosomal dominant and recessive inheritance of GRM7 mutation can cause disease spectrum phenotypes through ASD or ADHD to severe DD/ID and seizure with brain malformations.
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Affiliation(s)
- Majid Zaki-Dizaji
- Human Genetics Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Mohammad Foad Abazari
- Research Center for Clinical Virology, Tehran University of Medical Sciences, Tehran, Iran
- Island Medical Program, University of British Columbia, Victoria, British Columbia, Canada
| | - Hossein Razzaghi
- Human Genetics Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Irene Shkolnikov
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Brian R Christie
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
- Island Medical Program, University of British Columbia, Victoria, British Columbia, Canada
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van der Westhuizen ET. Single nucleotide variations encoding missense mutations in G protein-coupled receptors may contribute to autism. Br J Pharmacol 2024; 181:2158-2181. [PMID: 36787962 DOI: 10.1111/bph.16057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 12/21/2022] [Accepted: 02/04/2023] [Indexed: 02/16/2023] Open
Abstract
Autism is a neurodevelopmental condition with a range of symptoms that vary in intensity and severity from person to person. Genetic sequencing has identified thousands of genes containing mutations in autistic individuals, which may contribute to the development of autistic symptoms. Several of these genes encode G protein-coupled receptors (GPCRs), which are cell surface expressed proteins that transduce extracellular messages to the intracellular space. Mutations in GPCRs can impact their function, resulting in aberrant signalling within cells and across neurotransmitter systems in the brain. This review summarises the current knowledge on autism-associated single nucleotide variations encoding missense mutations in GPCRs and the impact of these genetic mutations on GPCR function. For some autism-associated mutations, changes in GPCR expression levels, ligand affinity, potency and efficacy have been observed. However, for many the functional consequences remain unknown. Thus, further work to characterise the functional impacts of the genetically identified mutations is required. LINKED ARTICLES: This article is part of a themed issue Therapeutic Targeting of G Protein-Coupled Receptors: hot topics from the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists 2021 Virtual Annual Scientific Meeting. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.14/issuetoc.
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Kamal MM, Teeya ST, Rahman MM, Talukder MEK, Sarmin S, Wani TA, Hasan MM. Prediction and assessment of deleterious and disease causing nonsynonymous single nucleotide polymorphisms (nsSNPs) in human FOXP4 gene: An in - silico study. Heliyon 2024; 10:e32791. [PMID: 38994097 PMCID: PMC11237951 DOI: 10.1016/j.heliyon.2024.e32791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Accepted: 06/10/2024] [Indexed: 07/13/2024] Open
Abstract
In humans, FOXP gene family is involved in embryonic development and cancer progression. The FOXP4 (Forkhead box protein P4) gene belongs to this FOXP gene family. FOXP4 gene plays a crucial role in oncogenesis. Single nucleotide polymorphisms are biological markers and common determinants of human diseases. Mutations can largely affect the function of the corresponding protein. Therefore, the molecular mechanism of nsSNPs in the FOXP4 gene needs to be elucidated. Initially, the SNPs of the FOXP4 gene were extracted from the dbSNP database and a total of 23124 SNPs was found, where 555 nonsynonymous, 20525 intronic, 1114 noncoding transcript, 334 synonymous were obtained and the rest were unspecified. Then, a series of bioinformatics tools (SIFT, PolyPhen2, SNAP2, PhD SNP, PANTHER, I-Mutant2.0, MUpro, GOR IV, ConSurf, NetSurfP 2.0, HOPE, DynaMut2, GeneMANIA, STRING and Schrodinger) were used to explore the effect of nsSNPs on FOXP4 protein function and structural stability. First, 555 nsSNPs were analyzed using SIFT, of which 57 were found as deleterious. Following, PolyPhen2, SNAP2, PhD SNP and PANTHER analyses, 10 nsSNPs (rs372762294, rs141899153, rs142575732, rs376938850, rs367607523, rs112517943, rs140387832, rs373949416, rs373949416 and rs376160648) were common and observed as deleterious, damaging and diseases associated. Following that, using I-Mutant2.0 and MUpro servers, 7 nsSNPs were found to be the most unstable. GOR IV predicted that these seven nsSNPs affect protein structure by altering the protein contents of alpha helixes, extended strands, and random coils. Following DynaMut2, 5 nsSNPs showed a decrease in the ΔΔG value compared with the wild-type and were found to be responsible for destabilizing the corresponding protein. GeneMANIA and STRING network revealed interaction of FOXP4 with other genes. Finally, molecular dynamics simulation analysis revealed consistent fluctuation in RMSD and RMSF values, Rg and hydrogen bonds in the mutant proteins compared with WT, which might alter the functional and structural stability of the corresponding protein. As a result, the aforementioned integrated comprehensive bioinformatic analyses provide insight into how various nsSNPs of the FOXP4 gene change the structural and functional properties of the corresponding protein, potentially proceeding with the pathophysiology of human diseases.
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Affiliation(s)
- Md Mostafa Kamal
- Department of Nutrition and Food Technology, Jashore University of Science and Technology, Jashore, 7408, Bangladesh
- Laboratory of Computational Biology, Biological Solution Centre, Jashore, 7408, Bangladesh
| | - Shamiha Tabassum Teeya
- Department of Nutrition and Food Technology, Jashore University of Science and Technology, Jashore, 7408, Bangladesh
| | - Md Mahfuzur Rahman
- Department of Genetic Engineering & Biotechnology, Bangabandhu Sheikh Mujibur Rahman Maritime University, Dhaka, 1216, Bangladesh
| | - Md Enamul Kabir Talukder
- Department of Genetic Engineering & Biotechnology, Jashore University of Science and Technology, Jashore, 7408, Bangladesh
- Laboratory of Computational Biology, Biological Solution Centre, Jashore, 7408, Bangladesh
| | - Sonia Sarmin
- BIRTAN-Bangladesh Institute of Research and Training on Applied Nutrition, Jhenaidah, 7300, Bangladesh
| | - Tanveer A Wani
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Md Mahmudul Hasan
- Department of Nutrition and Food Technology, Jashore University of Science and Technology, Jashore, 7408, Bangladesh
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Xiong GJ, Sheng ZH. Presynaptic perspective: Axonal transport defects in neurodevelopmental disorders. J Cell Biol 2024; 223:e202401145. [PMID: 38568173 PMCID: PMC10988239 DOI: 10.1083/jcb.202401145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 03/20/2024] [Accepted: 03/21/2024] [Indexed: 04/05/2024] Open
Abstract
Disruption of synapse assembly and maturation leads to a broad spectrum of neurodevelopmental disorders. Presynaptic proteins are largely synthesized in the soma, where they are packaged into precursor vesicles and transported into distal axons to ensure precise assembly and maintenance of presynapses. Due to their morphological features, neurons face challenges in the delivery of presynaptic cargos to nascent boutons. Thus, targeted axonal transport is vital to build functional synapses. A growing number of mutations in genes encoding the transport machinery have been linked to neurodevelopmental disorders. Emerging lines of evidence have started to uncover presynaptic mechanisms underlying axonal transport defects, thus broadening the view of neurodevelopmental disorders beyond postsynaptic mechanisms. In this review, we discuss presynaptic perspectives of neurodevelopmental disorders by focusing on impaired axonal transport and disturbed assembly and maintenance of presynapses. We also discuss potential strategies for restoring axonal transport as an early therapeutic intervention.
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Affiliation(s)
- Gui-Jing Xiong
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Zu-Hang Sheng
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
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De Pace R, Ghosh S, Ryan VH, Sohn M, Jarnik M, Rezvan Sangsari P, Morgan NY, Dale RK, Ward ME, Bonifacino JS. Messenger RNA transport on lysosomal vesicles maintains axonal mitochondrial homeostasis and prevents axonal degeneration. Nat Neurosci 2024; 27:1087-1102. [PMID: 38600167 PMCID: PMC11156585 DOI: 10.1038/s41593-024-01619-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 03/07/2024] [Indexed: 04/12/2024]
Abstract
In neurons, RNA granules are transported along the axon for local translation away from the soma. Recent studies indicate that some of this transport involves hitchhiking of RNA granules on lysosome-related vesicles. In the present study, we leveraged the ability to prevent transport of these vesicles into the axon by knockout of the lysosome-kinesin adaptor BLOC-one-related complex (BORC) to identify a subset of axonal mRNAs that depend on lysosome-related vesicles for transport. We found that BORC knockout causes depletion of a large group of axonal mRNAs mainly encoding ribosomal and mitochondrial/oxidative phosphorylation proteins. This depletion results in mitochondrial defects and eventually leads to axonal degeneration in human induced pluripotent stem cell (iPSC)-derived and mouse neurons. Pathway analyses of the depleted mRNAs revealed a mechanistic connection of BORC deficiency with common neurodegenerative disorders. These results demonstrate that mRNA transport on lysosome-related vesicles is critical for the maintenance of axonal homeostasis and that its failure causes axonal degeneration.
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Affiliation(s)
- Raffaella De Pace
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Saikat Ghosh
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Veronica H Ryan
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Mira Sohn
- Bioinformatics and Scientific Programming Core, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Michal Jarnik
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Paniz Rezvan Sangsari
- Biomedical Engineering and Physical Science Shared Resource, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Nicole Y Morgan
- Biomedical Engineering and Physical Science Shared Resource, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Ryan K Dale
- Bioinformatics and Scientific Programming Core, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Michael E Ward
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Juan S Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
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6
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De Pace R, Maroofian R, Paimboeuf A, Zamani M, Zaki MS, Sadeghian S, Azizimalamiri R, Galehdari H, Zeighami J, Williamson CD, Fleming E, Zhou D, Gannon JL, Thiffault I, Roze E, Suri M, Zifarelli G, Bauer P, Houlden H, Severino M, Patten SA, Farrow E, Bonifacino JS. Biallelic BORCS8 variants cause an infantile-onset neurodegenerative disorder with altered lysosome dynamics. Brain 2024; 147:1751-1767. [PMID: 38128568 PMCID: PMC11068110 DOI: 10.1093/brain/awad427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 09/30/2023] [Accepted: 12/02/2023] [Indexed: 12/23/2023] Open
Abstract
BLOC-one-related complex (BORC) is a multiprotein complex composed of eight subunits named BORCS1-8. BORC associates with the cytosolic face of lysosomes, where it sequentially recruits the small GTPase ARL8 and kinesin-1 and -3 microtubule motors to promote anterograde transport of lysosomes toward the peripheral cytoplasm in non-neuronal cells and the distal axon in neurons. The physiological and pathological importance of BORC in humans, however, remains to be determined. Here, we report the identification of compound heterozygous variants [missense c.85T>C (p.Ser29Pro) and frameshift c.71-75dupTGGCC (p.Asn26Trpfs*51)] and homozygous variants [missense c.196A>C (p.Thr66Pro) and c.124T>C (p.Ser42Pro)] in BORCS8 in five children with a severe early-infantile neurodegenerative disorder from three unrelated families. The children exhibit global developmental delay, severe-to-profound intellectual disability, hypotonia, limb spasticity, muscle wasting, dysmorphic facies, optic atrophy, leuko-axonopathy with hypomyelination, and neurodegenerative features with prevalent supratentorial involvement. Cellular studies using a heterologous transfection system show that the BORCS8 missense variants p.Ser29Pro, p.Ser42Pro and p.Thr66Pro are expressed at normal levels but exhibit reduced assembly with other BORC subunits and reduced ability to drive lysosome distribution toward the cell periphery. The BORCS8 frameshift variant p.Asn26Trpfs*51, on the other hand, is expressed at lower levels and is completely incapable of assembling with other BORC subunits and promoting lysosome distribution toward the cell periphery. Therefore, all the BORCS8 variants are partial or total loss-of-function alleles and are thus likely pathogenic. Knockout of the orthologous borcs8 in zebrafish causes decreased brain and eye size, neuromuscular anomalies and impaired locomotion, recapitulating some of the key traits of the human disease. These findings thus identify BORCS8 as a novel genetic locus for an early-infantile neurodegenerative disorder and highlight the critical importance of BORC and lysosome dynamics for the development and function of the central nervous system.
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Affiliation(s)
- Raffaella De Pace
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child, Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Reza Maroofian
- Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Adeline Paimboeuf
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, Laval, QC H7V 1B7, Canada
| | - Mina Zamani
- Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz 83151-61355, Iran
- Department of Molecular Genetics, Narges Medical Genetics and Prenatal Diagnosis Laboratory, Ahvaz 61556-89467, Iran
| | - Maha S Zaki
- Human Genetics and Genome Research Institute, Clinical Genetics Department, National Research Centre, Cairo 12622, Egypt
| | - Saeid Sadeghian
- Department of Pediatric Neurology, Golestan Medical, Educational, and Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz 61357-33184, Iran
| | - Reza Azizimalamiri
- Department of Pediatric Neurology, Golestan Medical, Educational, and Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz 61357-33184, Iran
| | - Hamid Galehdari
- Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz 83151-61355, Iran
| | - Jawaher Zeighami
- Department of Molecular Genetics, Narges Medical Genetics and Prenatal Diagnosis Laboratory, Ahvaz 61556-89467, Iran
| | - Chad D Williamson
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child, Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Emily Fleming
- Department of Genetics, Children’s Mercy Kansas City, Kansas City, MO 64108, USA
| | - Dihong Zhou
- Department of Genetics, Children’s Mercy Kansas City, Kansas City, MO 64108, USA
- Department of Pediatrics, University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108, USA
| | - Jennifer L Gannon
- Department of Pediatrics, University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108, USA
- Division of Clinical Genetics, Children’s Mercy Kansas City, Kansas City, MO 64108, USA
| | - Isabelle Thiffault
- Department of Genetics, Children’s Mercy Kansas City, Kansas City, MO 64108, USA
- Department of Pathology, Children's Mercy Kansas City, Kansas City, MO 64108, USA
| | - Emmanuel Roze
- Sorbonne Université, CNRS, INSERM, Institut du Cerveau (ICM), and Assistance Publique-Hôpitaux de Paris, Department of Neurology, Hôpital de la Pitié-Salpêtrière, Paris 75013, France
| | - Mohnish Suri
- Nottingham Clinical Genetics Service, Nottingham University Hospitals NHS Trust, City Hospital Campus, Nottingham NG5 1PB, UK
| | | | | | - Henry Houlden
- Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | | | - Shunmoogum A Patten
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, Laval, QC H7V 1B7, Canada
- Départementde Neurosciences, Université de Montréal, Montréal, QC H3C 3J7, Canada
| | - Emily Farrow
- Department of Pediatrics, University of Missouri-Kansas City School of Medicine, Kansas City, MO 64108, USA
- Genomic Medicine Center, Children’s Mercy Kansas City, Kansas City, MO 64108, USA
| | - Juan S Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child, Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
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Parent HH, Niswender CM. Therapeutic Potential for Metabotropic Glutamate Receptor 7 Modulators in Cognitive Disorders. Mol Pharmacol 2024; 105:348-358. [PMID: 38423750 PMCID: PMC11026152 DOI: 10.1124/molpharm.124.000874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/05/2024] [Accepted: 02/12/2024] [Indexed: 03/02/2024] Open
Abstract
Metabotropic glutamate receptor 7 (mGlu7) is the most highly conserved and abundantly expressed mGlu receptor in the human brain. The presynaptic localization of mGlu7, coupled with its low affinity for its endogenous agonist, glutamate, are features that contribute to the receptor's role in modulating neuronal excitation and inhibition patterns, including long-term potentiation, in various brain regions. These characteristics suggest that mGlu7 modulation may serve as a novel therapeutic strategy in disorders of cognitive dysfunction, including neurodevelopmental disorders that cause impairments in learning, memory, and attention. Primary mutations in the GRM7 gene have recently been identified as novel causes of neurodevelopmental disorders, and these patients exhibit profound intellectual and cognitive disability. Pharmacological tools, such as agonists, antagonists, and allosteric modulators, have been the mainstay for targeting mGlu7 in its endogenous homodimeric form to probe effects of its function and modulation in disease models. However, recent research has identified diversity in dimerization, as well as trans-synaptic interacting proteins, that also play a role in mGlu7 signaling and pharmacological properties. These novel findings represent exciting opportunities in the field of mGlu receptor drug discovery and highlight the importance of further understanding the functions of mGlu7 in complex neurologic conditions at both the molecular and physiologic levels. SIGNIFICANCE STATEMENT: Proper expression and function of mGlu7 is essential for learning, attention, and memory formation at the molecular level within neural circuits. The pharmacological targeting of mGlu7 is undergoing a paradigm shift by incorporating an understanding of receptor interaction with other cis- and trans- acting synaptic proteins, as well as various intracellular signaling pathways. Based upon these new findings, mGlu7's potential as a drug target in the treatment of cognitive disorders and learning impairments is primed for exploration.
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Affiliation(s)
- Harrison H Parent
- Department of Pharmacology (H.H.P., C.M.N.), Warren Center for Neuroscience Drug Discovery (H.H.P., C.M.N.), Vanderbilt Brain Institute (C.M.N.), and Vanderbilt Institute for Chemical Biology (C.M.N.), Vanderbilt University, Nashville, Tennessee; and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (C.M.N.)
| | - Colleen M Niswender
- Department of Pharmacology (H.H.P., C.M.N.), Warren Center for Neuroscience Drug Discovery (H.H.P., C.M.N.), Vanderbilt Brain Institute (C.M.N.), and Vanderbilt Institute for Chemical Biology (C.M.N.), Vanderbilt University, Nashville, Tennessee; and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (C.M.N.)
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8
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Januel L, Chatron N, Rivier-Ringenbach C, Cabet S, Labalme A, Sahin Y, Darvish H, Kruer M, Bakhtiari S, Sanlaville D, de Sainte Agathe JM, Lesca G. GRM7-related disorder: five additional patients from three independent families and review of the literature. Eur J Med Genet 2024; 67:104893. [PMID: 38070825 DOI: 10.1016/j.ejmg.2023.104893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 10/22/2023] [Accepted: 12/03/2023] [Indexed: 12/19/2023]
Abstract
Developmental and epileptic encephalopathies (DEEs) refer to a group of severe epileptic syndromes characterized by seizures as well as a developmental delay which can be a consequence of the underlying etiology and/or the epileptic encephalopathy. The genes responsible for DEEs are numerous and their number is increasing since the availability of Next-Generation Sequencing. Pathogenic variants in GRM7, encoding the metabotropic glutamate receptor 7, were recently shown as a cause of a severe DEE with autosomal recessive inheritance. To date, only ten patients have been reported in the literature, generally with severe phenotypes including early-onset epilepsy, microcephaly, brain anomalies, and spasticity. We report here 5 patients from 3 independent families with biallelic variants in the GRM7 gene. We review the literature and provide further elements for the understanding of the genotype-phenotype correlation of this rare syndrome.
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Affiliation(s)
- Louis Januel
- Hospices Civils de Lyon, Groupe Hospitalier Est, Service de Génétique, Bron, France.
| | - Nicolas Chatron
- Hospices Civils de Lyon, Groupe Hospitalier Est, Service de Génétique, Bron, France; Institut NeuroMyoGene PNMG, CNRS UMR5310, INSERM U1217, Université Claude Bernard Lyon 1, Lyon, France
| | | | - Sara Cabet
- Hospices Civils de Lyon, Groupe Hospitalier Est, Service de Radiologie, Bron, France
| | - Audrey Labalme
- Hospices Civils de Lyon, Groupe Hospitalier Est, Service de Génétique, Bron, France
| | | | - Hossein Darvish
- Pediatric Movement Disorders Program, Division of Pediatric Neurology, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Michael Kruer
- Pediatric Movement Disorders Program, Division of Pediatric Neurology, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Somayeh Bakhtiari
- Pediatric Movement Disorders Program, Division of Pediatric Neurology, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Damien Sanlaville
- Hospices Civils de Lyon, Groupe Hospitalier Est, Service de Génétique, Bron, France; Institut NeuroMyoGene PNMG, CNRS UMR5310, INSERM U1217, Université Claude Bernard Lyon 1, Lyon, France
| | | | - Gaetan Lesca
- Hospices Civils de Lyon, Groupe Hospitalier Est, Service de Génétique, Bron, France; Institut NeuroMyoGene PNMG, CNRS UMR5310, INSERM U1217, Université Claude Bernard Lyon 1, Lyon, France
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9
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Marom R, Zhang B, Washington ME, Song IW, Burrage LC, Rossi VC, Berrier AS, Lindsey A, Lesinski J, Nonet ML, Chen J, Baldridge D, Silverman GA, Sutton VR, Rosenfeld JA, Tran AA, Hicks MJ, Murdock DR, Dai H, Weis M, Jhangiani SN, Muzny DM, Gibbs RA, Caswell R, Pottinger C, Cilliers D, Stals K, Eyre D, Krakow D, Schedl T, Pak SC, Lee BH. Dominant negative variants in KIF5B cause osteogenesis imperfecta via down regulation of mTOR signaling. PLoS Genet 2023; 19:e1011005. [PMID: 37934770 PMCID: PMC10656020 DOI: 10.1371/journal.pgen.1011005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 11/17/2023] [Accepted: 10/03/2023] [Indexed: 11/09/2023] Open
Abstract
BACKGROUND Kinesin motor proteins transport intracellular cargo, including mRNA, proteins, and organelles. Pathogenic variants in kinesin-related genes have been implicated in neurodevelopmental disorders and skeletal dysplasias. We identified de novo, heterozygous variants in KIF5B, encoding a kinesin-1 subunit, in four individuals with osteogenesis imperfecta. The variants cluster within the highly conserved kinesin motor domain and are predicted to interfere with nucleotide binding, although the mechanistic consequences on cell signaling and function are unknown. METHODS To understand the in vivo genetic mechanism of KIF5B variants, we modeled the p.Thr87Ile variant that was found in two patients in the C. elegans ortholog, unc-116, at the corresponding position (Thr90Ile) by CRISPR/Cas9 editing and performed functional analysis. Next, we studied the cellular and molecular consequences of the recurrent p.Thr87Ile variant by microscopy, RNA and protein analysis in NIH3T3 cells, primary human fibroblasts and bone biopsy. RESULTS C. elegans heterozygous for the unc-116 Thr90Ile variant displayed abnormal body length and motility phenotypes that were suppressed by additional copies of the wild type allele, consistent with a dominant negative mechanism. Time-lapse imaging of GFP-tagged mitochondria showed defective mitochondria transport in unc-116 Thr90Ile neurons providing strong evidence for disrupted kinesin motor function. Microscopy studies in human cells showed dilated endoplasmic reticulum, multiple intracellular vacuoles, and abnormal distribution of the Golgi complex, supporting an intracellular trafficking defect. RNA sequencing, proteomic analysis, and bone immunohistochemistry demonstrated down regulation of the mTOR signaling pathway that was partially rescued with leucine supplementation in patient cells. CONCLUSION We report dominant negative variants in the KIF5B kinesin motor domain in individuals with osteogenesis imperfecta. This study expands the spectrum of kinesin-related disorders and identifies dysregulated signaling targets for KIF5B in skeletal development.
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Affiliation(s)
- Ronit Marom
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Texas Children’s Hospital, Houston, Texas, United States of America
| | - Bo Zhang
- Department of Pediatrics, Washington University School of Medicine, St Louis, Missouri, United States of America
| | - Megan E. Washington
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - I-Wen Song
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Lindsay C. Burrage
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Texas Children’s Hospital, Houston, Texas, United States of America
| | - Vittoria C. Rossi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Texas Children’s Hospital, Houston, Texas, United States of America
| | - Ava S. Berrier
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Anika Lindsey
- Department of Pediatrics, Washington University School of Medicine, St Louis, Missouri, United States of America
| | - Jacob Lesinski
- Department of Pediatrics, Washington University School of Medicine, St Louis, Missouri, United States of America
| | - Michael L. Nonet
- Department of Neuroscience, Washington University School of Medicine, St Louis, Missouri, United States of America
| | - Jian Chen
- Department of Genetics, Washington University School of Medicine, St Louis, Missouri, United States of America
| | - Dustin Baldridge
- Department of Pediatrics, Washington University School of Medicine, St Louis, Missouri, United States of America
| | - Gary A. Silverman
- Department of Pediatrics, Washington University School of Medicine, St Louis, Missouri, United States of America
| | - V. Reid Sutton
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Texas Children’s Hospital, Houston, Texas, United States of America
| | - Jill A. Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Alyssa A. Tran
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - M. John Hicks
- Texas Children’s Hospital, Houston, Texas, United States of America
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, Texas, United States of America
| | - David R. Murdock
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Hongzheng Dai
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - MaryAnn Weis
- Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington, United States of America
| | - Shalini N. Jhangiani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Donna M. Muzny
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Richard A. Gibbs
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Richard Caswell
- Exeter Genomics Laboratory, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom
| | - Carrie Pottinger
- All Wales Medical Genomics Service, Wrexham Maelor Hospital, Wrexham, UK
| | - Deirdre Cilliers
- Oxford Centre for Genomic Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Karen Stals
- Exeter Genomics Laboratory, Royal Devon University Healthcare NHS Foundation Trust, Exeter, United Kingdom
| | | | - David Eyre
- Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington, United States of America
| | - Deborah Krakow
- Human Genetics, Obstetrics & Gynecology, Orthopedic Surgery, University of California, Los Angeles, California, United States of America
| | - Tim Schedl
- Department of Genetics, Washington University School of Medicine, St Louis, Missouri, United States of America
| | - Stephen C. Pak
- Department of Pediatrics, Washington University School of Medicine, St Louis, Missouri, United States of America
| | - Brendan H. Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Texas Children’s Hospital, Houston, Texas, United States of America
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10
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Mir A, Song Y, Lee H, Khanahmad H, Khorram E, Nasiri J, Tabatabaiefar MA. Whole exome sequencing revealed variants in four genes underlying X-linked intellectual disability in four Iranian families: novel deleterious variants and clinical features with the review of literature. BMC Med Genomics 2023; 16:239. [PMID: 37821930 PMCID: PMC10566173 DOI: 10.1186/s12920-023-01680-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 10/01/2023] [Indexed: 10/13/2023] Open
Abstract
AIM AND OBJECTIVE Intellectual disability (ID) is a heterogeneous condition affecting brain development, function, and/or structure. The X-linked mode of inheritance of ID (X-linked intellectual disability; XLID) has a prevalence of 1 out of 600 to 1000 males. In the last decades, exome sequencing technology has revolutionized the process of disease-causing gene discovery in XLIDs. Nevertheless, so many of them still remain with unknown etiology. This study investigated four families with severe XLID to identify deleterious variants for possible diagnostics and prevention aims. METHODS Nine male patients belonging to four pedigrees were included in this study. The patients were studied genetically for Fragile X syndrome, followed by whole exome sequencing and analysis of intellectual disability-related genes variants. Sanger sequencing, co-segregation analysis, structural modeling, and in silico analysis were done to verify the causative variants. In addition, we collected data from previous studies to compare and situate our work with existing knowledge. RESULTS In three of four families, novel deleterious variants have been identified in three different genes, including ZDHHC9 (p. Leu189Pro), ATP2B3 (p. Asp847Glu), and GLRA2 (p. Arg350Cys) and also with new clinical features and in another one family, a reported pathogenic variant in the L1CAM (p. Glu309Lys) gene has been identified related to new clinical findings. CONCLUSION The current study's findings expand the existing knowledge of variants of the genes implicated in XLID and broaden the spectrum of phenotypes associated with the related conditions. The data have implications for genetic diagnosis and counseling.
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Affiliation(s)
- Atefeh Mir
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, 81746 73461, Iran
| | - Yongjun Song
- Division of Medical Genetics, 3Billion Inc, Seoul, South Korea
| | - Hane Lee
- Division of Medical Genetics, 3Billion Inc, Seoul, South Korea
| | - Hossein Khanahmad
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, 81746 73461, Iran
- Pediatric Inherited Diseases Research Center, Research Institute for Primordial Prevention of Noncommunicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Erfan Khorram
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, 81746 73461, Iran
| | - Jafar Nasiri
- Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohammad Amin Tabatabaiefar
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, 81746 73461, Iran.
- Pediatric Inherited Diseases Research Center, Research Institute for Primordial Prevention of Noncommunicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran.
- Deputy of Research and Technology, GenTArget Corp (GTAC), Isfahan University of Medical Sciences, Isfahan, Iran.
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11
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Masri AT, Oweis L, Ali M, Hamamy H. Global developmental delay and intellectual disability in the era of genomics: Diagnosis and challenges in resource limited areas. Clin Neurol Neurosurg 2023; 230:107799. [PMID: 37236004 DOI: 10.1016/j.clineuro.2023.107799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 05/12/2023] [Accepted: 05/22/2023] [Indexed: 05/28/2023]
Abstract
AIMS To report the diagnostic yield of clinical singleton whole exome sequencing (WES) performed among a group of Jordanian children presenting with global developmental delay /intellectual disability (GDD/ID), discuss the underlying identified genetic disorders and the challenges encountered. PATIENTS AND METHODS This retrospective medical record review study included 154 children who were diagnosed with GDD/ID at our clinic at Jordan University Hospital between 2016 and 2021, and whose diagnostic work up included WES. RESULTS Consanguinity among parents was reported in 94/154 (61.0%) patients and history of other affected siblings in 35/154 (22.7%) patients. Pathogenic and likely pathogenic variants (solved cases) were reported in 69/154 (44.8%) patients, a variant of uncertain significance was reported in 54/154 (35.0%) and a negative result was reported in 31/154 (20.1%) cases. In the solved cases, autosomal recessive diseases were the most common (33/69; 47.8%). Metabolic disorders were identified in 20/69 (28.9%) patients, followed by developmental and epileptic encephalopathies (9/69; 13.0%) and MECP2 related disorders (7/69; 10.1%). Other single gene disorders were identified in 33/69; 47.8%) patients. CONCLUSION This study had several limitations, as it was hospital-based and only including patients who were able to afford the test. Nevertheless, it yielded several important findings. In resource-limited countries, WES may be a reasonable approach. We discussed the challenges that clinicians meet in the context of shortage of resources.
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Affiliation(s)
- Amira T Masri
- Faculty of Medicine, Paediatric Department, Division of Child Neurology, The University of Jordan, Jordan.
| | - Liyana Oweis
- Faculty of Medicine, The University of Jordan, Jordan
| | - Majd Ali
- Faculty of Medicine, The University of Jordan, Jordan
| | - Hanan Hamamy
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland
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12
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Lei X, Hofmann CS, Rodriguez AL, Niswender CM. Differential Activity of Orthosteric Agonists and Allosteric Modulators at Metabotropic Glutamate Receptor 7. Mol Pharmacol 2023; 104:17-27. [PMID: 37105671 PMCID: PMC10289241 DOI: 10.1124/molpharm.123.000678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 03/23/2023] [Accepted: 03/28/2023] [Indexed: 04/29/2023] Open
Abstract
Metabotropic glutamate receptor 7 (mGlu7) is a G protein coupled receptor that has demonstrated promise as a therapeutic target across a number of neurologic and psychiatric diseases. Compounds that modulate the activity of mGlu7, such as positive and negative allosteric modulators, may represent new therapeutic strategies to modulate receptor activity. The endogenous neurotransmitter associated with the mGlu receptor family, glutamate, exhibits low efficacy and potency in activating mGlu7, and surrogate agonists, such as the compound L-(+)-2-Amino-4-phosphonobutyric acid (L-AP4), are often used for receptor activation and compound profiling. To understand the implications of the use of such agonists in the development of positive allosteric modulators (PAMs), we performed a systematic evaluation of receptor activation using a system in which mutations can be made in either protomer of the mGlu7 dimer; we employed mutations that prevent interaction with the orthosteric site as well as the G-protein coupling site of the receptor. We then measured increases in calcium levels downstream of a promiscuous G protein to assess the effects of mutations in one of the two protomers in the presence of two different agonists and three positive allosteric modulators. Our results reveal that distinct PAMs, for example N-[3-Chloro-4-[(5-chloro-2-pyridinyl)oxy]phenyl]-2-pyridinecarboxamide (VU0422288) and 3-(2,3-Difluoro-4-methoxyphenyl)-2,5-dimethyl-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine (VU6005649), do exhibit different maximal levels of potentiation with L-AP4 versus glutamate, but there appear to be common stable receptor conformations that are shared among all of the compounds examined here. SIGNIFICANCE STATEMENT: This manuscript describes the systematic evaluation of the mGlu7 agonists glutamate and L-(+)-2-Amino-4-phosphonobutyric acid (L-AP4) in the presence and absence of three distinct potentiators examining possible mechanistic differences. These findings demonstrate that mGlu7 potentiators display subtle variances in response to glutamate versus L-AP4.
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Affiliation(s)
- Xia Lei
- Department of Pharmacology (X.L., C.S.H., A.L.R., C.M.N.), Warren Center for Neuroscience Drug Discovery (X.L., A.L.R., C.M.N.), Vanderbilt Institute of Chemical Biology (C.M.N.), and Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennesee (C.M.N.); and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (C.M.N.)
| | - Christopher S Hofmann
- Department of Pharmacology (X.L., C.S.H., A.L.R., C.M.N.), Warren Center for Neuroscience Drug Discovery (X.L., A.L.R., C.M.N.), Vanderbilt Institute of Chemical Biology (C.M.N.), and Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennesee (C.M.N.); and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (C.M.N.)
| | - Alice L Rodriguez
- Department of Pharmacology (X.L., C.S.H., A.L.R., C.M.N.), Warren Center for Neuroscience Drug Discovery (X.L., A.L.R., C.M.N.), Vanderbilt Institute of Chemical Biology (C.M.N.), and Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennesee (C.M.N.); and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (C.M.N.)
| | - Colleen M Niswender
- Department of Pharmacology (X.L., C.S.H., A.L.R., C.M.N.), Warren Center for Neuroscience Drug Discovery (X.L., A.L.R., C.M.N.), Vanderbilt Institute of Chemical Biology (C.M.N.), and Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennesee (C.M.N.); and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (C.M.N.)
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13
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Nurchis MC, Altamura G, Riccardi MT, Radio FC, Chillemi G, Bertini ES, Garlasco J, Tartaglia M, Dallapiccola B, Damiani G. Whole genome sequencing diagnostic yield for paediatric patients with suspected genetic disorders: systematic review, meta-analysis, and GRADE assessment. Arch Public Health 2023; 81:93. [PMID: 37231492 DOI: 10.1186/s13690-023-01112-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 05/18/2023] [Indexed: 05/27/2023] Open
Abstract
BACKGROUND About 80% of the roughly 7,000 known rare diseases are single gene disorders, about 85% of which are ultra-rare, affecting less than one in one million individuals. NGS technologies, in particular whole genome sequencing (WGS) in paediatric patients suffering from severe disorders of likely genetic origin improve the diagnostic yield allowing targeted, effective care and management. The aim of this study is to perform a systematic review and meta-analysis to assess the effectiveness of WGS, with respect to whole exome sequencing (WES) and/or usual care, for the diagnosis of suspected genetic disorders among the paediatric population. METHODS A systematic review of the literature was conducted querying relevant electronic databases, including MEDLINE, EMBASE, ISI Web of Science, and Scopus from January 2010 to June 2022. A random-effect meta-analysis was run to inspect the diagnostic yield of different techniques. A network meta-analysis was also performed to directly assess the comparison between WGS and WES. RESULTS Of the 4,927 initially retrieved articles, thirty-nine met the inclusion criteria. Overall results highlighted a significantly higher pooled diagnostic yield for WGS, 38.6% (95% CI: [32.6 - 45.0]), in respect to WES, 37.8% (95% CI: [32.9 - 42.9]) and usual care, 7.8% (95% CI: [4.4 - 13.2]). The meta-regression output suggested a higher diagnostic yield of the WGS compared to WES after controlling for the type of disease (monogenic vs non-monogenic), with a tendency to better diagnostic performances for Mendelian diseases. The network meta-analysis showed a higher diagnostic yield for WGS compared to WES (OR = 1.54, 95%CI: [1.11 - 2.12]). CONCLUSIONS Although whole genome sequencing for the paediatric population with suspected genetic disorders provided an accurate and early genetic diagnosis in a high proportion of cases, further research is needed for evaluating costs, effectiveness, and cost-effectiveness of WGS and achieving an informed decision-making process. TRIAL REGISTRATION This systematic review has not been registered.
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Grants
- RF-2018-12,366,391, 2018 Ministero della Salute
- RF-2018-12,366,391, 2018 Ministero della Salute
- RF-2018-12,366,391, 2018 Ministero della Salute
- RF-2018-12,366,391, 2018 Ministero della Salute
- RF-2018-12,366,391, 2018 Ministero della Salute
- RF-2018-12,366,391, 2018 Ministero della Salute
- RF-2018-12,366,391, 2018 Ministero della Salute
- RF-2018-12,366,391, 2018 Ministero della Salute
- RF-2018-12,366,391, 2018 Ministero della Salute
- RF-2018-12,366,391, 2018 Ministero della Salute
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Affiliation(s)
- Mario Cesare Nurchis
- Department of Woman and Child Health and Public Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168, Rome, Italy
- School of Economics, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
| | - Gerardo Altamura
- Department of Health Sciences and Public Health, Section of Hygiene, Università Cattolica del Sacro Cuore, Largo Francesco Vito 1, 00168, Rome, Italy.
| | - Maria Teresa Riccardi
- Department of Health Sciences and Public Health, Section of Hygiene, Università Cattolica del Sacro Cuore, Largo Francesco Vito 1, 00168, Rome, Italy
| | - Francesca Clementina Radio
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù IRCCS, 00146, Rome, Italy
| | - Giovanni Chillemi
- Department for Innovation in Biological Agro-Food and Forest Systems (DIBAF), University of Tuscia, 01100, Viterbo, Italy
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies, Centro Nazionale Delle Ricerche, 70126, Bari, Italy
| | - Enrico Silvio Bertini
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù IRCCS, 00146, Rome, Italy
| | - Jacopo Garlasco
- Department of Public Health Sciences and Paediatrics, University of Turin, 10126, Turin, Italy
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù IRCCS, 00146, Rome, Italy
| | - Bruno Dallapiccola
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù IRCCS, 00146, Rome, Italy
| | - Gianfranco Damiani
- Department of Woman and Child Health and Public Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168, Rome, Italy
- Department of Health Sciences and Public Health, Section of Hygiene, Università Cattolica del Sacro Cuore, Largo Francesco Vito 1, 00168, Rome, Italy
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14
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Khorram E, Tabatabaiefar MA, Yaghini O, Khorrami M, Yazdani V, Fakhr F, Amini M, Kheirollahi M. Griscelli syndrome type 1: a novel pathogenic variant, and review of literature. Mol Genet Genomics 2023; 298:485-493. [PMID: 36651988 DOI: 10.1007/s00438-022-01971-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 10/28/2022] [Indexed: 01/19/2023]
Abstract
Griscelli syndrome type 1 (GS1) is a rare inherited autosomal recessive disease caused by a deleterious variant in the MYO5A gene and characterized by general hypopigmentation, neurological symptoms, motor disability, hypotonia, and vision abnormality. Only nine pathogenic variants in the MYO5A gene have been confirmed in association with the GS1. All of the reported pathogenic variants are truncating. Herein, two siblings from a consanguineous Iranian family with abnormal pigmentation and neurological symptoms were referred for genetic counseling. Whole-exome sequencing (WES) revealed a novel homozygous truncating variant c.1633_1634delAA (p.Asn545Glnfs*10) in the MYO5A gene, which was completely co-segregated with the phenotype in all affected and unaffected family members. Computational analysis and protein modeling demonstrated the deleterious effects of this variant on the structure and function of the protein. The variant, according to ACMG guidelines, was classified as pathogenic. Besides the novelty of the identified variant, our patients manifested more severe clinical symptoms and presented distal hyperlaxity in all four limbs, which was a new finding. In conclusion, we expanded the mutational and phenotypic spectrum of the GS1. Moreover, by studying clinical manifestations in all molecularly confirmed reported cases, provided a comprehensive overview of clinical presentation, and attempted to find a genotype-phenotype correlation.
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Affiliation(s)
- Erfan Khorram
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohammad Amin Tabatabaiefar
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Omid Yaghini
- Department of Pediatrics, School of Medicine, Growth and Development Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mehdi Khorrami
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Vida Yazdani
- Department of Biology, Islamic Azad University, East Tehran Branch, Tehran, Iran
| | - Fatemeh Fakhr
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Masoomeh Amini
- Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Majid Kheirollahi
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
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15
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Ghazarian TC, Hall MG, Horton LA, Miller BL, Rubin RT. Behavioral variant frontotemporal dementia in a 23-year-old man. Neurocase 2023; 29:6-13. [PMID: 36998234 PMCID: PMC10544695 DOI: 10.1080/13554794.2023.2191858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 03/10/2023] [Indexed: 04/01/2023]
Abstract
A 23-year-old man presented with behavioral disinhibition, stereotypies, motor apathy, flattened affect, and inappropriate laughter. CT demonstrated generalized cerebral atrophy. He was admitted with a diagnosis of unspecified psychosis and discharged on antipsychotic medication. He was readmitted 3 months later, was diagnosed with schizophrenia, and antipsychotic medication was continued. Owing to symptom progression and aggressive behavior, he was readmitted 2 months later. CT again demonstrated moderate central and cortical cerebral atrophy. MRI showed severe, stable atrophy with frontotemporal predominance, and he was diagnosed with probable behavioral variant frontotemporal dementia (bvFTD). Over the next year he rapidly deteriorated, with loss of cognitive abilities. Genetic testing revealed several variants, none of which are clearly disease-causing.
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Affiliation(s)
- Tania C. Ghazarian
- College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA
- Department of Psychiatry, Loma Linda University School of Medicine, Loma Linda, CA
| | - Matthew G.H. Hall
- Weill Institute for Neurosciences, Department of Neurology, and Memory and Aging Center, University of California San Francisco, San Francisco, CA
| | - Leslie A. Horton
- Psychiatry Residency Program, Community Memorial Health System, Ventura, CA
- Department of Psychiatry, Ventura County Medical Center, Ventura, CA
| | - Bruce L. Miller
- Weill Institute for Neurosciences, Department of Neurology, and Memory and Aging Center, University of California San Francisco, San Francisco, CA
| | - Robert T. Rubin
- Psychiatry Residency Program, Community Memorial Health System, Ventura, CA
- Department of Psychiatry, Ventura County Medical Center, Ventura, CA
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA
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16
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Kalbfleisch JJ, Rodriguez AL, Lei X, Weiss K, Blobaum AL, Boutaud O, Niswender CM, Lindsley CW. Persistent challenges in the development of an mGlu 7 PAM in vivo tool compound: The discovery of VU6046980. Bioorg Med Chem Lett 2023; 80:129106. [PMID: 36528230 PMCID: PMC10201562 DOI: 10.1016/j.bmcl.2022.129106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 12/06/2022] [Accepted: 12/11/2022] [Indexed: 12/16/2022]
Abstract
Herein, we report on the further chemical optimization of the first reported mGlu7 positive allosteric modulator (PAM), VU6027459. Replacement of the quinoline core by a cinnoline scaffold increased mGlu7 PAM potency by ∼ 10-fold, and concomitant introduction of a chiral tricyclic motif led to potent mGlu7 PAMs with enantioselective mGlu receptor selectivity profiles. Of these, VU6046980 emerged as a putative in vivo tool compound with excellent CNS penetration (Kp = 4.1; Kp,uu = 0.7) and efficacy in preclinical models. However, either off-target activity at the sigma-1 receptor or activity at a target not elucidated by large ancillary pharmacology panels led to sedation not driven by activation of mGlu7 (validated in Grm7 knockout mice). Thus, despite a significant advance, a viable mGlu7 PAM in vivo tool remains elusive.
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Affiliation(s)
- Jacob J Kalbfleisch
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Department of Chemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Alice L Rodriguez
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Xia Lei
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Kelly Weiss
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Annie L Blobaum
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Olivier Boutaud
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Colleen M Niswender
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Craig W Lindsley
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Department of Chemistry, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN 37232, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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17
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Feng Y, Zhang C, Wei Z, Li G, Gan Y, Liu C, Deng Y. Gene variations of glutamate metabolism pathway and epilepsy. ACTA EPILEPTOLOGICA 2022. [DOI: 10.1186/s42494-022-00103-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Epilepsy is a paroxysmal disorder of the brain, caused by an imbalance of neuronal excitation and inhibition. Glutamate is the most important excitatory neurotransmitter in the brain and plays an important role in epileptogenesis. Mutations in genes at any step/component of the glutamate metabolic pathway may lead to the development of epilepsy or epileptic encephalopathy.
Methods
Clinical history of 3 epilepsy patients with genetic variations of the glutamate metabolism pathway was collected. Electroencephalogram recording and magnetic resonance imaging were performed in each patient. We also reviewed recent literature for a variety of the genetic variations involved in epilepsy.
Results
Case 1 was a SLC1A2 mutation-carrier diagnosed with developmental and epileptic encephalopathy (DEE) 41, whose seizures decreased after start of the ketogenic diet. Case 2 carried a GRIN2A gene mutation and was seizure-free for three years after taking levetiracetam and vitamin B6. Case 3 was a GRIN2B mutation-carrier diagnosed with DEE 27, who seizures diminished after taking oxcarbazepine.
Conclusions
Preclinical and clinical evidence supports the therapeutic potential of glutamatergic signaling-targeting treatments for epilepsy. More studies are needed to discover novel DEE-related genetic mutations in the glutamate metabolic pathway.
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Salman DO, Mahfouz R, Bitar ER, Samaha J, Karam PE. Challenges of genetic diagnosis of inborn errors of metabolism in a major tertiary care center in Lebanon. Front Genet 2022; 13:1029947. [PMID: 36468010 PMCID: PMC9715967 DOI: 10.3389/fgene.2022.1029947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 11/08/2022] [Indexed: 01/25/2023] Open
Abstract
Background: Inborn errors of metabolism are rare genetic disorders; however, these are prevalent in countries with high consanguinity rates, like Lebanon. Patients are suspected, based on a combination of clinical and biochemical features; however, the final confirmation relies on genetic testing. Using next generation sequencing, as a new genetic investigational tool, carries several challenges for the physician, the geneticist, and the families. Methods: In this retrospective study, we analyzed the clinical, biochemical, and genetic profile of inborn errors of metabolism suspected patients, seen at a major tertiary care center in Lebanon, between 2015 and 2018. Genetic testing was performed using next generation sequencing. Genotype-phenotype correlation and diagnostic yield of each testing modality were studied. Results: Out of 211 patients genetically tested, 126 were suspected to have an inborn error of metabolism. The diagnostic yield of next generation sequencing reached 64.3%. Single gene testing was requested in 53%, whole exome sequencing in 36% and gene panels in 10%. Aminoacid disorders were mostly diagnosed followed by storage disorders, organic acidemias and mitochondrial diseases. Targeted testing was performed in 77% of aminoacid and organic acid disorders and half of suspected storage disorders. Single gene sequencing was positive in 75%, whereas whole exome sequencing diagnostic yield for complex cases, like mitochondrial disorders, reached 49%. Good clinical and biochemical correlation allowed the interpretation of variants of unknown significance and negative mutations as well as therapeutic management of most patients. Conclusion: Tailoring the choice of test modality, by next generation sequencing, to the category of suspected inborn errors of metabolism may lead to rapid diagnosis, shortcutting the cost of repeated testing. Whole exome sequencing as a first-tier investigation may be considered mainly for suspected mitochondrial diseases, whereas targeted sequencing can be offered upon suspicion of a specific enzyme deficiency. Timing and modality of gene test remain challenging, in view of the cost incurred by families.
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Affiliation(s)
- Doaa O. Salman
- Department of Pediatrics and Adolescent Medicine, American University of Beirut, Beirut, Lebanon
| | - Rami Mahfouz
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Elio R. Bitar
- Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Jinane Samaha
- Department of Pediatrics and Adolescent Medicine, American University of Beirut, Beirut, Lebanon,Inherited Metabolic Diseases Program, American University of Beirut Medical Center, Beirut, Lebanon
| | - Pascale E. Karam
- Department of Pediatrics and Adolescent Medicine, American University of Beirut, Beirut, Lebanon,Inherited Metabolic Diseases Program, American University of Beirut Medical Center, Beirut, Lebanon,*Correspondence: Pascale E. Karam,
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The diagnostic yield, candidate genes, and pitfalls for a genetic study of intellectual disability in 118 middle eastern families. Sci Rep 2022; 12:18862. [PMID: 36344539 PMCID: PMC9640568 DOI: 10.1038/s41598-022-22036-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 10/07/2022] [Indexed: 11/09/2022] Open
Abstract
Global Developmental Delay/Intellectual disability (ID) is the term used to describe various disorders caused by abnormal brain development and characterized by impairments in cognition, communication, behavior, or motor skills. In the past few years, whole-exome sequencing (WES) has been proven to be a powerful, robust, and scalable approach for candidate gene discoveries in consanguineous populations. In this study, we recruited 215 patients affected with ID from 118 Middle Eastern families. Whole-exome sequencing was completed for 188 individuals. The average age at which WES was completed was 8.5 years. Pathogenic or likely pathogenic variants were detected in 32/118 families (27%). Variants of uncertain significance were seen in 33/118 families (28%). The candidate genes with a possible association with ID were detected in 32/118 (27%) with a total number of 64 affected individuals. These genes are novel, were previously reported in a single family, or cause strikingly different phenotypes with a different mode of inheritance. These genes included: AATK, AP1G2, CAMSAP1, CCDC9B, CNTROB, DNAH14, DNAJB4, DRG1, DTNBP1, EDRF1, EEF1D, EXOC8, EXOSC4, FARSB, FBXO22, FILIP1, INPP4A, P2RX7, PRDM13, PTRHD1, SCN10A, SCYL2, SMG8, SUPV3L1, TACC2, THUMPD1, XPR1, ZFYVE28. During the 5 years of the study and through gene matching databases, several of these genes have now been confirmed as causative of ID. In conclusion, understanding the causes of ID will help understand biological mechanisms, provide precise counseling for affected families, and aid in primary prevention.
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Kane E, Beasley S, Schafer J, Bohl J, Lee Y, Rich K, Bosia E, Spratt D. Redefining the catalytic HECT domain boundaries for the HECT E3 ubiquitin ligase family. Biosci Rep 2022; 42:BSR20221036. [PMID: 36111624 PMCID: PMC9547173 DOI: 10.1042/bsr20221036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 09/07/2022] [Accepted: 09/08/2022] [Indexed: 11/17/2022] Open
Abstract
There are 28 unique human members of the homologous to E6AP C-terminus (HECT) E3 ubiquitin ligase family. Each member of the HECT E3 ubiquitin ligases contains a conserved bilobal HECT domain of approximately 350 residues found near their C-termini that is responsible for their respective ubiquitylation activities. Recent studies have begun to elucidate specific roles that each HECT E3 ubiquitin ligase has in various cancers, age-induced neurodegeneration, and neurological disorders. New structural models have been recently released for some of the HECT E3 ubiquitin ligases, but many HECT domain structures have yet to be examined due to chronic insolubility and/or protein folding issues. Building on these recently published structural studies coupled with our in-house experiments discussed in the present study, we suggest that the addition of ∼50 conserved residues preceding the N-terminal to the current UniProt defined boundaries of the HECT domain are required for isolating soluble, stable, and active HECT domains. We show using in silico bioinformatic analyses coupled with secondary structural prediction software that this predicted N-terminal α-helix found in all 28 human HECT E3 ubiquitin ligases forms an obligate amphipathic α-helix that binds to a hydrophobic pocket found within the HECT N-terminal lobe. The present study brings forth the proposal to redefine the residue boundaries of the HECT domain to include this N-terminal extension that will likely be critical for future biochemical, structural, and therapeutic studies on the HECT E3 ubiquitin ligase family.
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Affiliation(s)
- Emma I. Kane
- Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, 950 Main Street, Worcester, MA 01610, U.S.A
| | - Steven A. Beasley
- Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, 950 Main Street, Worcester, MA 01610, U.S.A
| | - Johanna M. Schafer
- Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, 950 Main Street, Worcester, MA 01610, U.S.A
| | - Justine E. Bohl
- Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, 950 Main Street, Worcester, MA 01610, U.S.A
| | - Young Sun Lee
- Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, 950 Main Street, Worcester, MA 01610, U.S.A
| | - Kayla J. Rich
- Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, 950 Main Street, Worcester, MA 01610, U.S.A
| | - Elizabeth F. Bosia
- Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, 950 Main Street, Worcester, MA 01610, U.S.A
| | - Donald E. Spratt
- Gustaf H. Carlson School of Chemistry and Biochemistry, Clark University, 950 Main Street, Worcester, MA 01610, U.S.A
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21
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Sánchez-Luquez KY, Carpena MX, Karam SM, Tovo-Rodrigues L. The contribution of whole-exome sequencing to intellectual disability diagnosis and knowledge of underlying molecular mechanisms: A systematic review and meta-analysis. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2022; 790:108428. [PMID: 35905832 DOI: 10.1016/j.mrrev.2022.108428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 07/21/2022] [Accepted: 07/23/2022] [Indexed: 01/01/2023]
Abstract
Whole-exome sequencing (WES) is useful for molecular diagnosis, family genetic counseling, and prognosis of intellectual disability (ID). However, ID molecular diagnosis ascertainment based on WES is highly dependent on de novo mutations (DNMs) and variants of uncertain significance (VUS). The quantification of DNM frequency in ID molecular diagnosis ascertainment and the biological mechanisms common to genes with VUS may provide objective information about WES use in ID diagnosis and etiology. We aimed to investigate and estimate the rate of ID molecular diagnostic assessment by WES, quantify the contribution of DNMs to this rate, and biologically and functionally characterize the genes whose mutations were identified through WES. A PubMed/Medline, Web of Science, Scopus, Science Direct, BIREME, and PsycINFO systematic review and meta-analysis was performed, including studies published between 2010 and 2022. Thirty-seven articles with data on ID molecular diagnostic yield using the WES approach were included in the review. WES testing accounted for an overall diagnostic rate of 42% (Confidence interval (CI): 35-50%), while the estimate restricted to DNMs was 11% (CI: 6-18%). Genetic information on mutations and genes was extracted and split into two groups: (1) genes whose mutation was used for positive molecular diagnosis, and (2) genes whose mutation led to uncertain molecular diagnosis. After functional enrichment analysis, in addition to their expected roles in neurodevelopment, genes from the first group were enriched in epigenetic regulatory mechanisms, immune system regulation, and circadian rhythm control. Genes from uncertain diagnosis cases were enriched in the renin angiotensin pathway. Taken together, our results support WES as an important approach to the molecular diagnosis of ID. The results also indicated relevant pathways that may underlie the pathogenesis of ID with the renin-angiotensin pathway being suggested to be a potential pathway underlying the pathogenesis of ID.
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Affiliation(s)
| | - Marina Xavier Carpena
- Postgraduate Program in Epidemiology, Universidade Federal de Pelotas, Pelotas, Brazil.
| | - Simone M Karam
- Postgraduate Program in Public Health, Universidade Federal do Rio Grande, Rio Grande, Brazil.
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Formation of the Mouse Internal Capsule and Cerebral Peduncle: A Pioneering Role for Striatonigral Axons as Revealed in Isl1 Conditional Mutants. J Neurosci 2022; 42:3344-3364. [PMID: 35273083 PMCID: PMC9034787 DOI: 10.1523/jneurosci.2291-21.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 02/09/2022] [Accepted: 02/13/2022] [Indexed: 01/05/2023] Open
Abstract
The projection neurons of the striatum, the principal nucleus of the basal ganglia, belong to one of the following two major pathways: the striatopallidal (indirect) pathway or the striatonigral (direct) pathway. Striatonigral axons project long distances and encounter ascending tracts (thalamocortical) while coursing alongside descending tracts (corticofugal) as they extend through the internal capsule and cerebral peduncle. These observations suggest that striatal circuitry may help to guide their trajectories. To investigate the developmental contributions of striatonigral axons to internal capsule formation, we have made use of Sox8-EGFP (striatal direct pathway) and Fezf2-TdTomato (corticofugal pathway) BAC transgenic reporter mice in combination with immunohistochemical markers to trace these axonal pathways throughout development. We show that striatonigral axons pioneer the internal capsule and cerebral peduncle and are temporally and spatially well positioned to provide guidance for corticofugal and thalamocortical axons. Using Isl1 conditional knock-out (cKO) mice, which exhibit disrupted striatonigral axon outgrowth, we observe both corticofugal and thalamocortical axon defects with either ventral forebrain- or telencephalon-specific Isl1 inactivation, despite Isl1 not being expressed in either cortical or thalamic projection neurons. Striatonigral axon defects can thus disrupt internal capsule formation. Our genome-wide transcriptomic analysis in Isl1 cKOs reveals changes in gene expression relevant to cell adhesion, growth cone dynamics, and extracellular matrix composition, suggesting potential mechanisms by which the striatonigral pathway exerts this guidance role. Together, our data support a novel pioneering role for the striatal direct pathway in the correct assembly of the ascending and descending axon tracts within the internal capsule and cerebral peduncle.SIGNIFICANCE STATEMENT The basal ganglia are a group of subcortical nuclei with established roles in the coordination of voluntary motor programs, aspects of cognition, and the selection of appropriate social behaviors. Hence, disruptions in basal ganglia connectivity have been implicated in the motor, cognitive, and social dysfunction characterizing common neurodevelopmental disorders such as attention-deficit/hyperactivity disorder, autism spectrum disorder, obsessive-compulsive disorder, and tic disorder. Here, we identified a novel role for the striatonigral (direct) pathway in pioneering the internal capsule and cerebral peduncle, and in guiding axons extending to and from the cortex. Our findings suggest that the abnormal development of basal ganglia circuits can drive secondary internal capsule defects and thereby may contribute to the pathology of these disorders.
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Stephenson SE, Costain G, Blok LE, Silk MA, Nguyen TB, Dong X, Alhuzaimi DE, Dowling JJ, Walker S, Amburgey K, Hayeems RZ, Rodan LH, Schwartz MA, Picker J, Lynch SA, Gupta A, Rasmussen KJ, Schimmenti LA, Klee EW, Niu Z, Agre KE, Chilton I, Chung WK, Revah-Politi A, Au PB, Griffith C, Racobaldo M, Raas-Rothschild A, Ben Zeev B, Barel O, Moutton S, Morice-Picard F, Carmignac V, Cornaton J, Marle N, Devinsky O, Stimach C, Wechsler SB, Hainline BE, Sapp K, Willems M, Bruel AL, Dias KR, Evans CA, Roscioli T, Sachdev R, Temple SE, Zhu Y, Baker JJ, Scheffer IE, Gardiner FJ, Schneider AL, Muir AM, Mefford HC, Crunk A, Heise EM, Millan F, Monaghan KG, Person R, Rhodes L, Richards S, Wentzensen IM, Cogné B, Isidor B, Nizon M, Vincent M, Besnard T, Piton A, Marcelis C, Kato K, Koyama N, Ogi T, Goh ESY, Richmond C, Amor DJ, Boyce JO, Morgan AT, Hildebrand MS, Kaspi A, Bahlo M, Friðriksdóttir R, Katrínardóttir H, Sulem P, Stefánsson K, Björnsson HT, Mandelstam S, Morleo M, Mariani M, Scala M, Accogli A, Torella A, Capra V, Wallis M, Jansen S, Waisfisz Q, de Haan H, Sadedin S, Lim SC, White SM, Ascher DB, Schenck A, Lockhart PJ, Christodoulou J, Tan TY, Christodoulou J, Tan TY. Germline variants in tumor suppressor FBXW7 lead to impaired ubiquitination and a neurodevelopmental syndrome. Am J Hum Genet 2022; 109:601-617. [PMID: 35395208 DOI: 10.1016/j.ajhg.2022.03.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 02/28/2022] [Indexed: 11/01/2022] Open
Abstract
Neurodevelopmental disorders are highly heterogenous conditions resulting from abnormalities of brain architecture and/or function. FBXW7 (F-box and WD-repeat-domain-containing 7), a recognized developmental regulator and tumor suppressor, has been shown to regulate cell-cycle progression and cell growth and survival by targeting substrates including CYCLIN E1/2 and NOTCH for degradation via the ubiquitin proteasome system. We used a genotype-first approach and global data-sharing platforms to identify 35 individuals harboring de novo and inherited FBXW7 germline monoallelic chromosomal deletions and nonsense, frameshift, splice-site, and missense variants associated with a neurodevelopmental syndrome. The FBXW7 neurodevelopmental syndrome is distinguished by global developmental delay, borderline to severe intellectual disability, hypotonia, and gastrointestinal issues. Brain imaging detailed variable underlying structural abnormalities affecting the cerebellum, corpus collosum, and white matter. A crystal-structure model of FBXW7 predicted that missense variants were clustered at the substrate-binding surface of the WD40 domain and that these might reduce FBXW7 substrate binding affinity. Expression of recombinant FBXW7 missense variants in cultured cells demonstrated impaired CYCLIN E1 and CYCLIN E2 turnover. Pan-neuronal knockdown of the Drosophila ortholog, archipelago, impaired learning and neuronal function. Collectively, the data presented herein provide compelling evidence of an F-Box protein-related, phenotypically variable neurodevelopmental disorder associated with monoallelic variants in FBXW7.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - John Christodoulou
- Murdoch Children's Research Institute, Melbourne, VIC 3052, Australia; Department of Paediatrics, University of Melbourne, Melbourne, VIC 3052, Australia; Victorian Clinical Genetics Services, Melbourne, VIC 3052, Australia
| | - Tiong Yang Tan
- Murdoch Children's Research Institute, Melbourne, VIC 3052, Australia; Department of Paediatrics, University of Melbourne, Melbourne, VIC 3052, Australia; Victorian Clinical Genetics Services, Melbourne, VIC 3052, Australia.
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Ceylan AC, Acar Arslan E, Erdem HB, Kavus H, Arslan M, Topaloğlu H. Autosomal recessive spinocerebellar ataxia 18 caused by homozygous exon 14 duplication in GRID2 and review of the literature. Acta Neurol Belg 2021; 121:1457-1462. [PMID: 32170608 DOI: 10.1007/s13760-020-01328-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Accepted: 02/29/2020] [Indexed: 01/19/2023]
Abstract
Autosomal recessive cerebellar ataxias (ARCA) are characterized by the abnormal structure of the cerebellum and spinal cord. Spinocerebellar ataxia type 18 (MIM 616204), one of the ARCA, is caused by the loss-of-function mutations of the GRID2 gene due to deletions. Missense mutations in the GRID2 cause ataxia with the gain-of-function mechanism. We report a homozygous GRID2 duplication in childhood-onset ataxia in two siblings. The clinical exome sequencing was performed on one of the siblings. No disease-causing mutations were reported as a result of the clinical exome test. Chromosomal microarray analysis was performed on the entire family using Affymetrix Optima® chips. Chromosomal microarray analysis showed a ~ 121-kb homozygous duplication of GRID2 (arr[GRCh37]4q22.2(94426536_94613158) × 4), including exon 14, in both siblings. Previously, GRID2 has been associated with an autosomal recessive (loss-of-function) and autosomal semi-dominant (gain-of-function) forms of ataxia. To the best of our knowledge, this is the first study to identify a homozygous duplication of GRID2 causing loss of function of the GluRD2 protein. These findings provide us with the conclusion that copy number variation analyses should be in the diagnostic process of autosomal recessive ataxia types.
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Rasheed M, Khan V, Harripaul R, Siddiqui M, Malik MA, Ullah Z, Zahid M, Vincent JB, Ansar M. Exome sequencing identifies novel and known mutations in families with intellectual disability. BMC Med Genomics 2021; 14:211. [PMID: 34452636 PMCID: PMC8399827 DOI: 10.1186/s12920-021-01066-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 08/25/2021] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Intellectual disability (ID) is a phenotypically and genetically heterogeneous disorder. METHODS In this study, genome wide SNP microarray and whole exome sequencing are used for the variant identification in eight Pakistani families with ID. Beside ID, most of the affected individuals had speech delay, facial dysmorphism and impaired cognitive abilities. Repetitive behavior was observed in MRID143, while seizures were reported in affected individuals belonging to MRID137 and MRID175. RESULTS In two families (MRID137b and MRID175), we identified variants in the genes CCS and ELFN1, which have not previously been reported to cause ID. In four families, variants were identified in ARX, C5orf42, GNE and METTL4. A copy number variation (CNV) was identified in IL1RAPL1 gene in MRID165. CONCLUSION These findings expand the existing knowledge of variants and genes implicated in autosomal recessive and X linked ID.
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Affiliation(s)
- Memoona Rasheed
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-I-Azam University, Islamabad, 45320, Pakistan
| | - Valeed Khan
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-I-Azam University, Islamabad, 45320, Pakistan
| | - Ricardo Harripaul
- Molecular Neuropsychiatry and Development (MiND) Lab, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, M5T 1R8, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Maimoona Siddiqui
- Division of Neurology, Shifa College of Medicine, H-8/1, Islamabad, Pakistan
| | - Madiha Amin Malik
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-I-Azam University, Islamabad, 45320, Pakistan
| | - Zahid Ullah
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-I-Azam University, Islamabad, 45320, Pakistan
| | - Muhammad Zahid
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-I-Azam University, Islamabad, 45320, Pakistan
| | - John B Vincent
- Molecular Neuropsychiatry and Development (MiND) Lab, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, M5T 1R8, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A8, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, M5T 1R8, Canada
| | - Muhammad Ansar
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-I-Azam University, Islamabad, 45320, Pakistan.
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Vincent KM, Eaton A, Yassaee VR, Miryounesi M, Hashemi-Gorji F, Rudichuk L, Goez H, Leonard N, Lazier J. Delineating the expanding phenotype of HERC2-related disorders: The impact of biallelic loss of function versus missense variation. Clin Genet 2021; 100:637-640. [PMID: 34370298 DOI: 10.1111/cge.14039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 07/06/2021] [Accepted: 07/24/2021] [Indexed: 11/28/2022]
Abstract
HECT And RLD Domain-Containing E3 Ubiquitin Protein Ligase 2, or HERC2, codes an ubiquitin ligase that has an important role in key cellular processes including cell cycle regulation, DNA repair, mitochondrial functions, and spindle formation during mitosis. While HERC2 Neurodevelopmental Disorder in Old Order Amish is a well characterized human disorder involving HERC2, bi-allelic HERC2 loss of function has only been described in three families and results in a more severe neurodevelopmental disorder. Herein, we delineate the HERC2 loss of function phenotype by describing three previously unreported patients, and by summarizing the molecular and phenotypic information of all known HERC2 missense variants and biallelic loss of function patients. Collectively, these twelve individuals present with recurring features that define a syndrome with varying combinations of severe neurodevelopmental delay, structural brain anomalies, seizures, hypotonia, feeding difficulties, hearing and vision issues, and renal anomalies. This study describes a distinct neurodevelopmental disorder, emphasizing the importance of further characterization of HERC2-related disorders, as well as highlighting the importance of ongoing work into understanding these critical neurodevelopmental pathways.
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Affiliation(s)
- Krista M Vincent
- Department of Medical Genetics, Children's Hospital of Eastern Ontario, Ottawa, Canada
| | - Alison Eaton
- Department of Medical Genetics, University of Alberta, Edmonton, Canada
| | - Vahid Reza Yassaee
- Genomic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Miryounesi
- Genomic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Lauren Rudichuk
- Department of Medical Genetics, University of Alberta, Edmonton, Canada
| | - Helly Goez
- Department of Pediatrics, University of Alberta, Edmonton, Canada
| | - Norma Leonard
- Department of Medical Genetics, University of Alberta, Edmonton, Canada.,Women's and Children's Research Institute, Edmonton, Canada
| | - Joanna Lazier
- Department of Medical Genetics, Children's Hospital of Eastern Ontario, Ottawa, Canada.,Department of Medical Genetics, University of Alberta, Edmonton, Canada.,Women's and Children's Research Institute, Edmonton, Canada
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Jdila MB, Mignon-Ravix C, Ncir SB, Kammoun F, Fakhfakh F, Villard L, Triki C. A large consanguineous family with a homozygous Metabotropic Glutamate Receptor 7 (mGlu7) variant and developmental epileptic encephalopathy: Effect on protein structure and ligand affinity. Orphanet J Rare Dis 2021; 16:317. [PMID: 34273994 PMCID: PMC8286605 DOI: 10.1186/s13023-021-01951-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 07/11/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Developmental and epileptic encephalopathies (DEE) are chronic neurological conditions where epileptic activity contributes to the progressive disruption of brain function, frequently leading to impaired motor, cognitive and sensory development. PATIENTS AND METHODS The present study reports a clinical investigation and a molecular analysis by Next Generation Sequencing (NGS) of a large consanguineous family comprising several cases of developmental and epileptic encephalopathy. Bioinformatic prediction and molecular docking analysis were also carried out. RESULTS The majority of patients in our studied family had severe developmental impairments, early-onset seizures, brain malformations such as cortical atrophy and microcephaly, developmental delays and intellectual disabilities. The molecular investigations revealed a novel homozygous variant c.1411G>A (p.Gly471Arg) in the GRM7 gene which was segregating with the disease in the family. Bioinformatic tools predicted its pathogenicity and docking analysis revealed its potential effects on mGlu7 protein binding to its ligand. CONCLUSION Our results contribute to a better understanding of the impact of GRM7 variants for the newly described associated phenotype.
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Affiliation(s)
- Marwa Ben Jdila
- Research Laboratory 'NeuroPédiatrie' (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia. .,Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, Sfax University, Sfax, Tunisia.
| | | | - Sihem Ben Ncir
- Research Laboratory 'NeuroPédiatrie' (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia.,Child Neurology Department, Hedi Chaker Universitary Hospital of Sfax, Sfax, Tunisia
| | - Fatma Kammoun
- Research Laboratory 'NeuroPédiatrie' (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia.,Child Neurology Department, Hedi Chaker Universitary Hospital of Sfax, Sfax, Tunisia
| | - Faiza Fakhfakh
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, Sfax University, Sfax, Tunisia
| | - Laurent Villard
- Inserm, MMG, Aix Marseille Univ, Marseille, France.,Département de Génétique Médicale, Hôpital d'Enfants de la Timone, Assistance Publique Hôpitaux de Marseille, 13385, Marseille, France
| | - Chahnez Triki
- Research Laboratory 'NeuroPédiatrie' (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia.,Child Neurology Department, Hedi Chaker Universitary Hospital of Sfax, Sfax, Tunisia
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De Pace R, Britt DJ, Mercurio J, Foster AM, Djavaherian L, Hoffmann V, Abebe D, Bonifacino JS. Synaptic Vesicle Precursors and Lysosomes Are Transported by Different Mechanisms in the Axon of Mammalian Neurons. Cell Rep 2021; 31:107775. [PMID: 32553155 PMCID: PMC7478246 DOI: 10.1016/j.celrep.2020.107775] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 04/07/2020] [Accepted: 05/26/2020] [Indexed: 01/08/2023] Open
Abstract
BORC is a multisubunit complex previously shown to promote coupling of mammalian lysosomes and C. elegans synaptic vesicle (SV) precursors (SVPs) to kinesins for anterograde transport of these organelles along microtubule tracks. We attempted to meld these observations into a unified model for axonal transport in mammalian neurons by testing two alternative hypotheses: (1) that SV and lysosomal proteins are co-transported within a single type of “lysosome-related vesicle” and (2) that SVPs and lysosomes are distinct organelles, but both depend on BORC for axonal transport. Analyses of various types of neurons from wild-type rats and mice, as well as from BORC-deficient mice, show that neither hypothesis is correct. We find that SVPs and lysosomes are transported separately, but only lysosomes depend on BORC for axonal transport in these neurons. These findings demonstrate that SVPs and lysosomes are distinct organelles that rely on different machineries for axonal transport in mammalian neurons. De Pace et al. show that lysosomes and synaptic vesicle precursors (SVPs) are distinct organelles that move separately from the soma to the axon in rat and mouse neurons. Moreover, they demonstrate that the BLOC-1-related complex (BORC) is required for the transport of lysosomes but not SVPs in mouse neurons.
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Affiliation(s)
- Raffaella De Pace
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dylan J Britt
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jeffrey Mercurio
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Arianne M Foster
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lucas Djavaherian
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Victoria Hoffmann
- Division of Veterinary Resources, National Institutes of Health, Bethesda, MD 20892, USA
| | - Daniel Abebe
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Juan S Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
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The Utility of Whole Exome Sequencing in Diagnosing Pediatric Neurological Disorders. Balkan J Med Genet 2021; 23:17-24. [PMID: 33816068 PMCID: PMC8009565 DOI: 10.2478/bjmg-2020-0028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Pediatric neurological disorders have a wide spectrum of clinical presentations and can be challenging to diagnose. Whole exome sequencing (WES) is increasingly becoming an integral diagnostic tool in medicine. It is cost-effective and has high diagnostic yield, especially in consanguineous populations. This study aims to review WES results and its value in diagnosing neurological disorders. A retrospective chart review was performed for WES results between the period of January 2018 to November 2019. Whole exome sequencing was requested for children with unexplained neurological signs and symptoms such as epilepsy, developmental delay, visual impairment, spasticity, hypotonia and magnetic resonance imaging (MRI) brain changes. It was conducted for children in a pediatric neurology clinic of a tertiary center at Jeddah, Saudi Arabia. Twenty-six children with undiagnosed neurological conditions were identified and underwent WES diagnosis. Nineteen patients (73.0%) of the cohort were diagnosed with pathogenic variants, likely pathogenic variants or variants of unknown significance (VUS). Consanguinity was positive in 18 families of the cohort (69.0%). Seven patients showed homozygous mutations. Five patients had heterozygous mutations. There were six patients with VUS and six patients had negative WES results. Whole exome sequencing showed a high diagnostic rate in this group of children with variable neurological disorders.
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Wang J, Liu Z, Xu M, Han X, Ren C, Yang X, Zhang C, Fang F. Cinical, Metabolic, and Genetic Analysis and Follow-Up of Eight Patients With HIBCH Mutations Presenting With Leigh/Leigh-Like Syndrome. Front Pharmacol 2021; 12:605803. [PMID: 33762937 PMCID: PMC7982470 DOI: 10.3389/fphar.2021.605803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 01/22/2021] [Indexed: 11/26/2022] Open
Abstract
3-Hydroxyisobutyryl-CoA hydrolase (HIBCH, NM_014362.3) gene mutation can cause HIBCH deficiency, leading to Leigh/Leigh-like disease. To date, few case series have investigated the relationship between metabolites and clinical phenotypes or the effects of treatment, although 34 patients with HIBCH mutations from 27 families have been reported. The purpose of this study was to analyze the phenotypic spectrum, follow-up results, metabolites, and genotypes of patients with HIBCH deficiency presenting with Leigh/Leigh-like syndrome and explore specific metabolites related to disease diagnosis and prognosis through retrospective and longitudinal studies. Applying next-generation sequencing, we identified eight patients with HIBCH mutations from our cohort of 181 cases of genetically diagnosed Leigh/Leigh-like syndrome. Six novel HIBCH mutations were identified: c.977T>G [p.Leu326Arg], c.1036G>T [p.Val346Phe], c.750+1G>A, c.810-2A>C, c.469C>T [p.Arg157*], and c.236delC [p.Pro79Leufs*5]. The Newcastle Pediatric Mitochondrial Disease Scale (NPMDS) was employed to assess disease progression and clinical outcomes. The non-invasive approach of metabolite analysis showed that levels of some were associated with clinical phenotype severity. Five (5/7) patients presented with elevated C4-OH in dried blood spots, and the level was probably correlated with the NPMDS scores during the peak disease phase. 2,3-Dihydroxy-2-methylbutyrate in urine was elevated in six (6/7) patients and elevated S-(2-caboxypropyl)cysteamine in urine was found in three patients (3/3). The median age at initial presentation was 13 months (8–18 months), and the median follow-up was 2.3 years (range 1.3–7.2 years). We summarized and compared with all reported patients with HIBCH mutations. The most prominent clinical manifestations were developmental regression/delay, hypotonia, encephalopathy, and feeding difficulties. We administered drug and dietary treatment. During follow-up, five patients responded positively to treatment with a significant decrease in NPMDS scores. Our research is the largest case series of patients with HIBCH mutations.
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Affiliation(s)
- Junling Wang
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Zhimei Liu
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Manting Xu
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Xiaodi Han
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Changhong Ren
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Xinying Yang
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Chunhua Zhang
- Department of Research, Development of MILS International, Ishikawa, Japan
| | - Fang Fang
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
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31
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Snijders Blok L, Vino A, den Hoed J, Underhill HR, Monteil D, Li H, Reynoso Santos FJ, Chung WK, Amaral MD, Schnur RE, Santiago-Sim T, Si Y, Brunner HG, Kleefstra T, Fisher SE. Heterozygous variants that disturb the transcriptional repressor activity of FOXP4 cause a developmental disorder with speech/language delays and multiple congenital abnormalities. Genet Med 2021; 23:534-542. [PMID: 33110267 PMCID: PMC7935712 DOI: 10.1038/s41436-020-01016-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 10/06/2020] [Accepted: 10/09/2020] [Indexed: 11/08/2022] Open
Abstract
PURPOSE Heterozygous pathogenic variants in various FOXP genes cause specific developmental disorders. The phenotype associated with heterozygous variants in FOXP4 has not been previously described. METHODS We assembled a cohort of eight individuals with heterozygous and mostly de novo variants in FOXP4: seven individuals with six different missense variants and one individual with a frameshift variant. We collected clinical data to delineate the phenotypic spectrum, and used in silico analyses and functional cell-based assays to assess pathogenicity of the variants. RESULTS We collected clinical data for six individuals: five individuals with a missense variant in the forkhead box DNA-binding domain of FOXP4, and one individual with a truncating variant. Overlapping features included speech and language delays, growth abnormalities, congenital diaphragmatic hernia, cervical spine abnormalities, and ptosis. Luciferase assays showed loss-of-function effects for all these variants, and aberrant subcellular localization patterns were seen in a subset. The remaining two missense variants were located outside the functional domains of FOXP4, and showed transcriptional repressor capacities and localization patterns similar to the wild-type protein. CONCLUSION Collectively, our findings show that heterozygous loss-of-function variants in FOXP4 are associated with an autosomal dominant neurodevelopmental disorder with speech/language delays, growth defects, and variable congenital abnormalities.
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Affiliation(s)
- Lot Snijders Blok
- Human Genetics Department, Radboud University Medical Center, Nijmegen, The Netherlands.
- Language & Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands.
| | - Arianna Vino
- Language & Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
| | - Joery den Hoed
- Language & Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
| | - Hunter R Underhill
- Department of Pediatrics, Division of Medical Genetics, University of Utah, Salt Lake City, UT, USA
| | - Danielle Monteil
- Department of Pediatrics, Naval Medical Center, Portsmouth, VA, USA
| | - Hong Li
- Department of Human Genetics, Emory University, Atlanta, GA, USA
| | - Francis Jeshira Reynoso Santos
- Department of Genetics, Joe DiMaggio Children's Hospital, Hollywood, FL, USA
- Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Wendy K Chung
- Department of Pediatrics, Columbia University Irving Medical Center, New York, NY, USA
| | | | | | | | - Yue Si
- GeneDx, Gaithersburg, MD, USA
| | - Han G Brunner
- Human Genetics Department, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Clinical Genetics, MHeNS School of Neuroscience, and GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Tjitske Kleefstra
- Human Genetics Department, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Simon E Fisher
- Language & Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.
- Donders Institute for Brain, Cognition & Behaviour, Radboud University, Nijmegen, The Netherlands.
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32
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Fisher NM, AlHashim A, Buch AB, Badivuku H, Samman MM, Weiss KM, Cestero GI, Does MD, Rook JM, Lindsley CW, Conn PJ, Gogliotti RG, Niswender CM. A GRM7 mutation associated with developmental delay reduces mGlu7 expression and produces neurological phenotypes. JCI Insight 2021; 6:143324. [PMID: 33476302 PMCID: PMC7934925 DOI: 10.1172/jci.insight.143324] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 01/13/2021] [Indexed: 12/29/2022] Open
Abstract
The metabotropic glutamate receptor 7 (mGlu7) is a G protein–coupled receptor that has been recently linked to neurodevelopmental disorders. This association is supported by the identification of GRM7 variants in patients with autism spectrum disorder, attention deficit hyperactivity disorder, and severe developmental delay. One GRM7 mutation previously reported in 2 patients results in a single amino acid change, I154T, within the mGlu7 ligand-binding domain. Here, we report 2 new patients with this mutation who present with severe developmental delay and epilepsy. Functional studies of the mGlu7-I154T mutant reveal that this substitution resulted in significant loss of mGlu7 protein expression in HEK293A cells and in mice. We show that this occurred posttranscriptionally at the level of protein expression and trafficking. Similar to mGlu7–global KO mice, mGlu7-I154T animals exhibited reduced motor coordination, deficits in contextual fear learning, and seizures. This provides functional evidence that a disease-associated mutation affecting the mGlu7 receptor was sufficient to cause neurological dysfunction in mice and further validates GRM7 as a disease-causing gene in the human population.
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Affiliation(s)
- Nicole M Fisher
- Department of Pharmacology and.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | | | - Aditi B Buch
- Department of Pharmacology and.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - Hana Badivuku
- Department of Pharmacology and.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | | | - Kelly M Weiss
- Department of Pharmacology and.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - Gabriela I Cestero
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, USA
| | - Mark D Does
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, USA
| | - Jerri M Rook
- Department of Pharmacology and.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - Craig W Lindsley
- Department of Pharmacology and.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA.,Department of Chemistry and.,Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - P Jeffrey Conn
- Department of Pharmacology and.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee USA
| | - Rocco G Gogliotti
- Department of Pharmacology and.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA.,Department of Molecular Pharmacology and Neuroscience, Loyola University Chicago, Maywood, Illinois, USA
| | - Colleen M Niswender
- Department of Pharmacology and.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee USA
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33
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Masri A, Hamamy H. Cost Effectiveness of Whole Exome Sequencing for Children with Developmental Delay in a Developing Country: A Study from Jordan. JOURNAL OF PEDIATRIC NEUROLOGY 2021. [DOI: 10.1055/s-0040-1722265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AbstractThis retrospective study aimed to determine the cost effectiveness of whole exome sequencing (WES) in the diagnosis of children with developmental delay in a developing country. In this study of 40 patients, the average cost of traditional investigations and indirect costs related to rehabilitation and medications per child were USD847 and 6,585 per year, respectively. With a current cost for WES of approximately USD1,200, we concluded that performing WES could be cost effective, even in countries with limited resources, as it provides the option for genetic counseling in affected families with an ultimate reduction of overall financial burden to both parents and health care system.
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Affiliation(s)
- Amira Masri
- Division of Child Neurology, Department of Pediatrics, Faculty of Medicine, The University of Jordan, Amman, Jordan
| | - Hanan Hamamy
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland
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MRI of 3-hydroxyisobutyryl-CoA hydrolase (HIBCH) deficiency. Radiol Case Rep 2021; 16:807-810. [PMID: 33552330 PMCID: PMC7846898 DOI: 10.1016/j.radcr.2021.01.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 01/06/2021] [Accepted: 01/11/2021] [Indexed: 11/30/2022] Open
Abstract
3-Hydroxyisobutyryl-CoA hydrolase (HIBCH) deficiency is a rare mitochondrial disorder of valine metabolism which may present with motor delay, hypotonia, ataxia, dystonia, seizures poor feeding, and organic aciduria. Neuroimaging findings include signal abnormalities of the deep gray matter, particularly the globus pallidi, and cerebral peduncles. We report a 15-month-old male patient with HIBCH deficiency who presented with paroxysmal tonic upgaze of infancy, motor delay, and hypotonia. MRI revealed characteristic bilateral, symmetric signal abnormalities in the basal ganglia and a mutation in HIBCH was confirmed with whole exome sequencing. HIBCH should be a consideration in patients with Leigh-like features, especially if neuroimaging changes primarily affect the globus pallidi. Recognition of this pattern may help guide targeted testing and expedite the diagnosis and treatment of this rare disease.
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35
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Pathogenic GRM7 Mutations Associated with Neurodevelopmental Disorders Impair Axon Outgrowth and Presynaptic Terminal Development. J Neurosci 2021; 41:2344-2359. [PMID: 33500274 DOI: 10.1523/jneurosci.2108-20.2021] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 01/11/2021] [Accepted: 01/16/2021] [Indexed: 12/18/2022] Open
Abstract
Metabotropic glutamate receptor 7 (mGlu7) is an inhibitory heterotrimeric G-protein-coupled receptor that modulates neurotransmitter release and synaptic plasticity at presynaptic terminals in the mammalian central nervous system. Recent studies have shown that rare mutations in glutamate receptors and synaptic scaffold proteins are associated with neurodevelopmental disorders (NDDs). However, the role of presynaptic mGlu7 in the pathogenesis of NDDs remains largely unknown. Recent whole-exome sequencing (WES) studies in families with NDDs have revealed that several missense mutations (c.1865G>A:p.R622Q; c.461T>C:p.I154T; c.1972C>T:p.R658W and c.2024C>A:p.T675K) or a nonsense mutation (c.1757G>A:p.W586X) in the GRM7 gene may be linked to NDDs. In the present study, we investigated the mechanistic links between GRM7 point mutations and NDD pathology. We find that the pathogenic GRM7 I154T and R658W/T675K mutations lead to the degradation of the mGlu7 protein. In particular, the GRM7 R658W/T675K mutation results in a lack of surface mGlu7 expression in heterologous cells and cultured neurons isolated from male and female rat embryos. We demonstrate that the expression of mGlu7 variants or exposure to mGlu7 antagonists impairs axon outgrowth through the mitogen-activated protein kinase (MAPK)-cAMP-protein kinase A (PKA) signaling pathway during early neuronal development, which subsequently leads to a decrease in the number of presynaptic terminals in mature neurons. Treatment with an mGlu7 agonist restores the pathologic phenotypes caused by mGlu7 I154T but not by mGlu7 R658W/T675K because of its lack of neuronal surface expression. These findings provide evidence that stable neuronal surface expression of mGlu7 is essential for neural development and that mGlu7 is a promising therapeutic target for NDDs.SIGNIFICANCE STATEMENT Neurodevelopmental disorders (NDDs) affect brain development and function by multiple etiologies. Metabotropic glutamate receptor 7 (mGlu7) is a receptor that controls excitatory neurotransmission and synaptic plasticity. Since accumulating evidence indicates that the GRM7 gene locus is associated with NDD risk, we analyzed the functional effects of human GRM7 variants identified in patients with NDDs. We demonstrate that stable neuronal surface expression of mGlu7 is essential for axon outgrowth and presynaptic terminal development in neurons. We found that mitogen-activated protein kinase (MAPK)-cAMP-protein kinase A (PKA) signaling and subsequent cytoskeletal dynamics are defective because of the degradation of mGlu7 variants. Finally, we show that the defects caused by mGlu7 I154T can be reversed by agonists, providing the rationale for proposing mGlu7 as a potential therapeutic target for NDDs.
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Yokotsuka-Ishida S, Nakamura M, Tomiyasu Y, Nagai M, Kato Y, Tomiyasu A, Umehara H, Hayashi T, Sasaki N, Ueno SI, Sano A. Positional cloning and comprehensive mutation analysis identified a novel KDM2B mutation in a Japanese family with minor malformations, intellectual disability, and schizophrenia. J Hum Genet 2021; 66:597-606. [PMID: 33402700 DOI: 10.1038/s10038-020-00889-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/25/2020] [Accepted: 11/29/2020] [Indexed: 11/09/2022]
Abstract
The importance of epigenetic control in the development of the central nervous system has recently been attracting attention. Methylation patterns of lysine 4 and lysine 36 in histone H3 (H3K4 and H3K36) in the central nervous system are highly conserved among species. Numerous complications of body malformations and neuropsychiatric disorders are due to abnormal histone H3 methylation modifiers. In this study, we analyzed a Japanese family with a dominant inheritance of symptoms including Marfan syndrome-like minor physical anomalies (MPAs), intellectual disability, and schizophrenia (SCZ). We performed positional cloning for this family using a single nucleotide polymorphism (SNP) array and whole-exome sequencing, which revealed a missense coding strand mutation (rs1555289644, NM_032590.4: c.2173G>A, p.A725T) in exon 15 on the plant homeodomain of the KDM2B gene as a possible cause of the disease in the family. The exome sequencing revealed that within the coding region, only a point mutation in KDM2B was present in the region with the highest logarithm of odds score of 2.41 resulting from whole genome linkage analysis. Haplotype analysis revealed co-segregation with four affected family members (IV-9, III-4, IV-5, and IV-8). Lymphoblastoid cell lines from the proband with this mutation showed approximately halved KDM2B expression in comparison with healthy controls. KDM2B acts as an H3K4 and H3K36 histone demethylase. Our findings suggest that haploinsufficiency of KDM2B in the process of development, like other H3K4 and H3K36 methylation modifiers, may have caused MPAs, intellectual disability, and SCZ in this Japanese family.
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Affiliation(s)
- Saeko Yokotsuka-Ishida
- Department of Psychiatry, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Masayuki Nakamura
- Department of Psychiatry, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
| | - Yoko Tomiyasu
- Department of Psychiatry, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Mio Nagai
- Division of Psychiatry, Matsuyama Red Cross Hospital, Matsuyama, Japan
| | - Yuko Kato
- Division of Psychiatry, Jiundo Hospital, Tokyo, Japan
| | - Akiyuki Tomiyasu
- Department of Psychiatry, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Hiromi Umehara
- Department of Psychiatry, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Takehiro Hayashi
- Department of Social Welfare, The International University of Kagoshima, Kagoshima, Japan
| | - Natsuki Sasaki
- Department of Psychiatry, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Shu-Ichi Ueno
- Department of Neuropsychiatry, Ehime University Graduate School of Medicine Toon, Kagoshima, Japan
| | - Akira Sano
- Department of Psychiatry, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
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Mone F, Doyle S, Ahmad A, Abu Subieh H, Hamilton S, Allen S, Marton T, Williams D, Kilby MD. Diagnostic and perinatal outcomes in consanguineous couples with a structural fetal anomaly: A cohort study. Acta Obstet Gynecol Scand 2020; 100:418-424. [PMID: 33128783 DOI: 10.1111/aogs.14036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 10/13/2020] [Accepted: 10/20/2020] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Consanguineous unions occur when a couple are related outside marriage and is associated with adverse genetic and perinatal outcomes for affected offspring. The objectives of this study were to evaluate: (i) background characteristics, (ii) uptake of prenatal and postnatal investigation and (iii) diagnostic outcomes of UK consanguineous couples presenting with a fetal structural anomaly. MATERIAL AND METHODS This was a retrospective and partly prospective cohort study comparing consanguineous (n = 62) and non-consanguineous (n = 218) pregnancies with current or previous fetal structural anomalies reviewed in a UK prenatal genetic clinic from 2008 to 2019. Outcomes were compared using odds ratios (OR). RESULTS Most consanguineous couples were of Pakistani ethnicity (odds ratio [OR] 29, 95% confidence interval [95% CI] 13-62) and required use of an interpreter [OR 9, 95% CI 4-20). In the consanguineous group, the uptake of prenatal invasive testing was lower (OR 0.4, 95% CI 0.2-0.7) and the number declining follow up was greater (OR 10, 95% CI 3-34) than in the non-consanguineous group. This likely explained the lower proportion of consanguineous couples where a final definitive unifying diagnosis to explain the fetal structural anomalies was reached (OR 0.3, 95% CI 0.2-0.6). When a diagnosis was obtained in this group, it was always postnatal and most often using genomic sequencing technologies (OR 6, 95% CI 1-27). The risk of perinatal death was greater (OR 3, 95% CI 1-6) in the consanguineous group, as was the risk of fetal structural anomaly recurrence in a subsequent pregnancy (OR 4, 95% CI 1-13). There was no difference in the uptake of perinatal autopsy or termination of pregnancy between groups. CONCLUSIONS Consanguineous couples are a vulnerable group in the prenatal setting. Although adverse perinatal outcomes in this group are more common secondary to congenital anomalies, despite the evolution of genomic sequencing technologies, due to a lower uptake of prenatal testing it is less likely that a unifying diagnosis is obtained and recurrence can occur. There is a need for proactive genetic counseling and education from the multidisciplinary team, addressing language barriers as well as religious and cultural beliefs in an attempt to optimize reproductive options.
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Affiliation(s)
- Fionnuala Mone
- Fetal Medicine Centre, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK.,Institute of Metabolism and Systems Research, College of Medical & Dental Sciences, University of Birmingham, Birmingham, UK
| | - Samantha Doyle
- West Midlands Regional Genetics Laboratory and Clinical Genetics Service, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Asfa Ahmad
- West Midlands Regional Genetics Laboratory and Clinical Genetics Service, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Hala Abu Subieh
- Fetal Medicine Centre, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Susan Hamilton
- West Midlands Regional Genetics Laboratory and Clinical Genetics Service, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Stephanie Allen
- West Midlands Regional Genetics Laboratory and Clinical Genetics Service, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Tamas Marton
- West Midland's Perinatal Pathology Service, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Denise Williams
- West Midlands Regional Genetics Laboratory and Clinical Genetics Service, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Mark D Kilby
- Fetal Medicine Centre, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK.,Institute of Metabolism and Systems Research, College of Medical & Dental Sciences, University of Birmingham, Birmingham, UK
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Keren-Kaplan T, Bonifacino JS. ARL8 Relieves SKIP Autoinhibition to Enable Coupling of Lysosomes to Kinesin-1. Curr Biol 2020; 31:540-554.e5. [PMID: 33232665 DOI: 10.1016/j.cub.2020.10.071] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 09/16/2020] [Accepted: 10/23/2020] [Indexed: 01/24/2023]
Abstract
Long-range movement of organelles within the cytoplasm relies on coupling to microtubule motors, a process that is often mediated by adaptor proteins. In many cases, this coupling involves organelle- or adaptor-induced activation of the microtubule motors by conformational reversal of an autoinhibited state. Herein, we show that a similar regulatory mechanism operates for an adaptor protein named SKIP (also known as PLEKHM2). SKIP binds to the small guanosine triphosphatase (GTPase) ARL8 on the lysosomal membrane to couple lysosomes to the anterograde microtubule motor kinesin-1. Structure-function analyses of SKIP reveal that the C-terminal region comprising three pleckstrin homology (PH) domains interacts with the N-terminal region comprising ARL8- and kinesin-1-binding sites. This interaction inhibits coupling of lysosomes to kinesin-1 and, consequently, lysosome movement toward the cell periphery. We also find that ARL8 does not just recruit SKIP to the lysosomal membrane but also relieves SKIP autoinhibition, promoting kinesin-1-driven, anterograde lysosome transport. Finally, our analyses show that the largely disordered middle region of SKIP mediates self-association and that this self-association enhances the interaction of SKIP with kinesin-1. These findings indicate that SKIP is not just a passive connector of lysosome-bound ARL8 to kinesin-1 but is itself subject to intra- and inter-molecular interactions that regulate its function. We anticipate that similar organelle- or GTPase-induced conformational changes could regulate the activity of other kinesin adaptors.
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Affiliation(s)
- Tal Keren-Kaplan
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Juan S Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
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39
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Reed CW, Kalbfleisch JJ, Wong MJ, Washecheck JP, Hunter A, Rodriguez AL, Blobaum AL, Conn PJ, Niswender CM, Lindsley CW. Discovery of VU6027459: A First-in-Class Selective and CNS Penetrant mGlu 7 Positive Allosteric Modulator Tool Compound. ACS Med Chem Lett 2020; 11:1773-1779. [PMID: 32944146 DOI: 10.1021/acsmedchemlett.0c00432] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 08/20/2020] [Indexed: 01/07/2023] Open
Abstract
Herein, we report the discovery of the first selective and CNS penetrant mGlu7 PAM (VU6027459) derived from a "molecular switch" within a selective mGlu7 NAM chemotype. VU6027459 displayed CNS penetration in both mice (Kp = 2.74) and rats (Kp= 4.78), it was orally bioavailable in rats (%F = 69.5), and undesired activity at DAT was ablated.
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Affiliation(s)
- Carson W Reed
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Jacob J Kalbfleisch
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Madison J Wong
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Jordan P Washecheck
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Ashton Hunter
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Alice L Rodriguez
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Anna L Blobaum
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - P Jeffrey Conn
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States.,Vanderbilt Kennedy Center, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Colleen M Niswender
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States.,Vanderbilt Kennedy Center, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - Craig W Lindsley
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37232, United States.,Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States.,Warren Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
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40
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Co M, Anderson AG, Konopka G. FOXP transcription factors in vertebrate brain development, function, and disorders. WILEY INTERDISCIPLINARY REVIEWS. DEVELOPMENTAL BIOLOGY 2020; 9:e375. [PMID: 31999079 PMCID: PMC8286808 DOI: 10.1002/wdev.375] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 12/17/2019] [Accepted: 01/08/2020] [Indexed: 12/22/2022]
Abstract
FOXP transcription factors are an evolutionarily ancient protein subfamily coordinating the development of several organ systems in the vertebrate body. Association of their genes with neurodevelopmental disorders has sparked particular interest in their expression patterns and functions in the brain. Here, FOXP1, FOXP2, and FOXP4 are expressed in distinct cell type-specific spatiotemporal patterns in multiple regions, including the cortex, hippocampus, amygdala, basal ganglia, thalamus, and cerebellum. These varied sites and timepoints of expression have complicated efforts to link FOXP1 and FOXP2 mutations to their respective developmental disorders, the former affecting global neural functions and the latter specifically affecting speech and language. However, the use of animal models, particularly those with brain region- and cell type-specific manipulations, has greatly advanced our understanding of how FOXP expression patterns could underlie disorder-related phenotypes. While many questions remain regarding FOXP expression and function in the brain, studies to date have illuminated the roles of these transcription factors in vertebrate brain development and have greatly informed our understanding of human development and disorders. This article is categorized under: Nervous System Development > Vertebrates: General Principles Gene Expression and Transcriptional Hierarchies > Gene Networks and Genomics Nervous System Development > Vertebrates: Regional Development.
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Affiliation(s)
- Marissa Co
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, Oregon
| | - Ashley G Anderson
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Genevieve Konopka
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas
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41
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Rapid Whole-Exome Sequencing as a Diagnostic Tool in a Neonatal/Pediatric Intensive Care Unit. J Clin Med 2020; 9:jcm9072220. [PMID: 32668698 PMCID: PMC7408678 DOI: 10.3390/jcm9072220] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/03/2020] [Accepted: 07/10/2020] [Indexed: 12/21/2022] Open
Abstract
Genetic disorders are the leading cause of infant morbidity and mortality. Due to the large number of genetic diseases, molecular and phenotype heterogeneity and often severe course, these diseases remain undiagnosed. In infants with a suspected acute monogenic disease, rapid whole-exome sequencing (R-WES) can be successfully performed. R-WES (singletons) was performed in 18 unrelated infants with a severe and/or progressing disease with the suspicion of genetic origin hospitalized in an Intensive Care Unit (ICU). Blood samples were also collected from the parents. The results from the R-WES were available after 5-14 days. A conclusive genetic diagnosis was obtained in 13 children, corresponding to an overall diagnostic yield of 72.2%. For nine patients, R-WES was used as a first-tier test. Eight patients were diagnosed with inborn errors of metabolism, mainly mitochondrial diseases. In two patients, the disease was possibly caused by variants in genes which so far have not been associated with human disease (NARS1 and DCAF5). R-WES proved to be an effective diagnostic tool for critically ill infants in ICUs suspected of having a genetic disorder. It also should be considered as a first-tier test after precise clinical description. The quickly obtained diagnosis impacts patient's medical management, and families can receive genetic counseling.
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42
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Hetzelt KLML, Kraus C, Kusnik S, Thiel CT, Uebe S, Ekici AB, Trollmann R, Reis A, Zweier C. A case of severe autosomal recessive spinocerebellar ataxia type 18 with a novel nonsense variant in GRID2. Eur J Med Genet 2020; 63:103998. [PMID: 32622959 DOI: 10.1016/j.ejmg.2020.103998] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/12/2020] [Accepted: 06/28/2020] [Indexed: 12/20/2022]
Abstract
Autosomal-recessive spinocerebellar ataxia type 18 (SCAR18) is a rare neurologic disorder. It is caused by bi-allelic aberrations in the GRID2 gene, encoding an ionotropic glutamate receptor. In total, 20 affected individuals with mainly homozygous/compound heterozygous intragenic deletions/duplications, two different missense variants and one nonsense variant in GRID2 have been reported, so far. SCAR18 is characterized by delayed psychomotor development, intellectual disability, severely impaired gait due to cerebellar ataxia, ocular movement abnormalities, and cerebellar atrophy in brain imaging. By trio exome sequencing, we now identified a novel homozygous nonsense variant (c.568C > T; p.Gln190*) in GRID2 in a four year old female from a consanguineous family who presented with a particularly severe manifestation of SCAR18. The girl was born after an uneventful pregnancy and showed early-onset, profoundly delayed psychomotor development with no achieved psychomotor milestones at age 4 years. Additionally, she presented with severe muscular hypotonia, progressive truncal and appendicular ataxia, binocular vertical nystagmus, central hearing loss and incomplete loss of sight. She was dystrophic, interacted only very little and had behavioral anomalies such as eating hair and bruxism. Brain imaging showed cerebellar hypoplasia, extended cerebrospinal fluid spaces and beginning reduction of cerebral volume. Our findings further delineate the mutational and clinical spectrum of GRID2-associated spinocerebellar ataxia type 18 and indicate that homozygous nonsense variants are possibly associated with the severe end of the SCAR18 phenotypic spectrum.
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Affiliation(s)
- Katalin L M L Hetzelt
- Institute of Human Genetics, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg FAU, Erlangen, Germany
| | - Cornelia Kraus
- Institute of Human Genetics, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg FAU, Erlangen, Germany
| | - Stefan Kusnik
- Department of Pediatrics, Division of Pediatric Neurology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg FAU, Erlangen, Germany
| | - Christian T Thiel
- Institute of Human Genetics, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg FAU, Erlangen, Germany
| | - Steffen Uebe
- Institute of Human Genetics, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg FAU, Erlangen, Germany
| | - Arif B Ekici
- Institute of Human Genetics, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg FAU, Erlangen, Germany
| | - Regina Trollmann
- Department of Pediatrics, Division of Pediatric Neurology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg FAU, Erlangen, Germany
| | - André Reis
- Institute of Human Genetics, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg FAU, Erlangen, Germany
| | - Christiane Zweier
- Institute of Human Genetics, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg FAU, Erlangen, Germany.
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43
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Kılıç M, Kurt-Çolak F. 3-Hydroxyisobutyryl-CoA Hydrolase Deficiency in a Turkish Child with a Novel HIBCH Gene Mutation and Literature Review. Mol Syndromol 2020. [DOI: 10.1159/000508728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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44
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Blackburn PR, Schultz MJ, Lahner CA, Li D, Bhoj E, Fisher LJ, Renaud DL, Kenney A, Ibrahim N, Hashem M, Zain Seidahmed M, Hasadsri L, Schrier Vergano SA, Alkuraya FS, Lanpher BC. Expanding the clinical and phenotypic heterogeneity associated with biallelic variants in ACO2. Ann Clin Transl Neurol 2020; 7:1013-1028. [PMID: 32519519 PMCID: PMC7318087 DOI: 10.1002/acn3.51074] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 05/08/2020] [Accepted: 05/10/2020] [Indexed: 11/06/2022] Open
Abstract
OBJECTIVE We describe the clinical characteristics and genetic etiology of several new cases within the ACO2-related disease spectrum. Mitochondrial aconitase (ACO2) is a nuclear-encoded tricarboxylic acid cycle enzyme. Homozygous pathogenic missense variants in the ACO2 gene were initially associated with infantile degeneration of the cerebrum, cerebellum, and retina, resulting in profound intellectual and developmental disability and early death. Subsequent studies have identified a range of homozygous and compound heterozygous pathogenic missense, nonsense, frameshift, and splice-site ACO2 variants in patients with a spectrum of clinical manifestations and disease severities. METHODS We describe a cohort of five novel patients with biallelic pathogenic variants in ACO2. We review the clinical histories of these patients as well as the molecular and functional characterization of the associated ACO2 variants and compare with those described previously in the literature. RESULTS Two siblings with relatively mild symptoms presented with episodic ataxia, mild developmental delays, severe dysarthria, and behavioral abnormalities including hyperactivity and depressive symptoms with generalized anxiety. One patient presented with the classic form with cerebellar hypoplasia, ataxia, seizures, optic atrophy, and retinitis pigmentosa. Another unrelated patient presented with ataxia but developed severe progressive spastic quadriplegia. Another patient demonstrated a spinal muscular atrophy-like presentation with severe neonatal hypotonia, diminished reflexes, and poor respiratory drive, leading to ventilator dependence until death at the age of 9 months. INTERPRETATION In this study, we highlight the importance of recognizing milder forms of the disorder, which may escape detection due to atypical disease presentation.
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Affiliation(s)
- Patrick R Blackburn
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Matthew J Schultz
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Carrie A Lahner
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Dong Li
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Elizabeth Bhoj
- Center for Applied Genomics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Laura J Fisher
- Department of Clinical Genomics, Mayo Clinic, Rochester, Minnesota
| | - Deborah L Renaud
- Departments of Neurology and Pediatrics, Mayo Clinic, Rochester, Minnesota
| | - Amy Kenney
- Division of Medical Genetics and Metabolism, Children's Hospital of The King's Daughters, Norfolk, Virginia
| | - Niema Ibrahim
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mais Hashem
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mohammed Zain Seidahmed
- Division of Neonatology, Department of Pediatrics, Security Forces Hospital, Riyadh, Saudi Arabia
| | - Linda Hasadsri
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Samantha A Schrier Vergano
- Division of Medical Genetics and Metabolism, Children's Hospital of The King's Daughters, Norfolk, Virginia.,Department of Pediatrics, Eastern Virginia Medical School, Norfolk, Virginia
| | - Fowzan S Alkuraya
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia.,Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
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45
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Palombo F, Graziano C, Al Wardy N, Nouri N, Marconi C, Magini P, Severi G, La Morgia C, Cantalupo G, Cordelli DM, Gangarossa S, Al Kindi MN, Al Khabouri M, Salehi M, Giorgio E, Brusco A, Pisani F, Romeo G, Carelli V, Pippucci T, Seri M. Autozygosity-driven genetic diagnosis in consanguineous families from Italy and the Greater Middle East. Hum Genet 2020; 139:1429-1441. [PMID: 32488467 DOI: 10.1007/s00439-020-02187-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 05/25/2020] [Indexed: 12/12/2022]
Abstract
Autozygosity-driven exome analysis has been shown effective for identification of genes underlying recessive diseases especially in countries of the so-called Greater Middle East (GME), where high consanguinity unravels the phenotypic effects of recessive alleles and large family sizes facilitate homozygosity mapping. In Italy, as in most European countries, consanguinity is estimated low. Nonetheless, consanguineous Italian families are not uncommon in publications of genetic findings and are often key to new associations of genes with rare diseases. We collected 52 patients from 47 consanguineous families with suspected recessive diseases, 29 originated in GME countries and 18 of Italian descent. We performed autozygosity-driven exome analysis by detecting long runs of homozygosity (ROHs > 1.5 Mb) and by prioritizing candidate clinical variants within. We identified a pathogenic synonymous variant that had been previously missed in NARS2 and we increased an initial high diagnostic rate (47%) to 55% by matchmaking our candidate genes and including in the analysis shorter ROHs that may also happen to be autozygous. GME and Italian families contributed to diagnostic yield comparably. We found no significant difference either in the extension of the autozygous genome, or in the distribution of candidate clinical variants between GME and Italian families, while we showed that the average autozygous genome was larger and the mean number of candidate clinical variants was significantly higher (p = 0.003) in mutation-positive than in mutation-negative individuals, suggesting that these features influence the likelihood that the disease is autozygosity-related. We highlight the utility of autozygosity-driven genomic analysis also in countries and/or communities, where consanguinity is not widespread cultural tradition.
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Affiliation(s)
- Flavia Palombo
- Medical Genetics Sant'Orsola, Malpighi University Hospital of Bologna, Via Massarenti 9, 40138, Bologna, Italy.,IRCCS Istituto Delle Scienze Neurologiche Di Bologna, UOC Clinica Neurologica, Bologna, Italy
| | - Claudio Graziano
- Medical Genetics Sant'Orsola, Malpighi University Hospital of Bologna, Via Massarenti 9, 40138, Bologna, Italy
| | - Nadia Al Wardy
- Department of Biochemistry, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Nayereh Nouri
- Department of Genetics and Molecular Biology, Isfahan University of Medical Sciences, Isfahan, Iran.,Craniofacial and Cleft Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Caterina Marconi
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Bologna, Italy
| | - Pamela Magini
- Medical Genetics Sant'Orsola, Malpighi University Hospital of Bologna, Via Massarenti 9, 40138, Bologna, Italy
| | - Giulia Severi
- Medical Genetics Sant'Orsola, Malpighi University Hospital of Bologna, Via Massarenti 9, 40138, Bologna, Italy
| | - Chiara La Morgia
- IRCCS Istituto Delle Scienze Neurologiche Di Bologna, UOC Clinica Neurologica, Bologna, Italy.,Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
| | - Gaetano Cantalupo
- Child Neuropsychiatry, Department of Surgical Sciences, Dentistry, Gynecology and Pediatrics, University of Verona, Verona, Italy.,UOC Neuropsichiatria Infantile, DAI Materno-Infantile, AOUI Verona, Verona, Italy
| | - Duccio Maria Cordelli
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Bologna, Italy.,Neuropsychiatry Sant'Orsola-Malpighi University Hospital of Bologna, Bologna, Italy
| | | | - Mohammed Nasser Al Kindi
- Department of Biochemistry, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman
| | - Mazin Al Khabouri
- Department of Biochemistry, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Oman.,Department of ENT, Al Nahdha Hospital, Ministry of Health, Muscat, Oman
| | - Mansoor Salehi
- Department of Genetics and Molecular Biology, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Elisa Giorgio
- Department of Medical Sciences, University of Torino, Turin, Italy
| | - Alfredo Brusco
- Department of Medical Sciences, University of Torino, Turin, Italy
| | - Francesco Pisani
- Child Neuropsychiatry Unit, Department of Medicine & Surgery, University of Parma, Parma, Italy
| | - Giovanni Romeo
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Bologna, Italy
| | - Valerio Carelli
- IRCCS Istituto Delle Scienze Neurologiche Di Bologna, UOC Clinica Neurologica, Bologna, Italy.,Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
| | - Tommaso Pippucci
- Medical Genetics Sant'Orsola, Malpighi University Hospital of Bologna, Via Massarenti 9, 40138, Bologna, Italy.
| | - Marco Seri
- Medical Genetics Sant'Orsola, Malpighi University Hospital of Bologna, Via Massarenti 9, 40138, Bologna, Italy.,Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Bologna, Italy
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Fisher NM, Gould RW, Gogliotti RG, McDonald AJ, Badivuku H, Chennareddy S, Buch AB, Moore AM, Jenkins MT, Robb WH, Lindsley CW, Jones CK, Conn PJ, Niswender CM. Phenotypic profiling of mGlu 7 knockout mice reveals new implications for neurodevelopmental disorders. GENES BRAIN AND BEHAVIOR 2020; 19:e12654. [PMID: 32248644 DOI: 10.1111/gbb.12654] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 03/03/2020] [Accepted: 03/26/2020] [Indexed: 12/17/2022]
Abstract
Neurodevelopmental disorders are characterized by deficits in communication, cognition, attention, social behavior and/or motor control. Previous studies have pointed to the involvement of genes that regulate synaptic structure and function in the pathogenesis of these disorders. One such gene, GRM7, encodes the metabotropic glutamate receptor 7 (mGlu7 ), a G protein-coupled receptor that regulates presynaptic neurotransmitter release. Mutations and polymorphisms in GRM7 have been associated with neurodevelopmental disorders in clinical populations; however, limited preclinical studies have evaluated mGlu7 in the context of this specific disease class. Here, we show that the absence of mGlu7 in mice is sufficient to alter phenotypes within the domains of social behavior, associative learning, motor function, epilepsy and sleep. Moreover, Grm7 knockout mice exhibit an attenuated response to amphetamine. These findings provide rationale for further investigation of mGlu7 as a potential therapeutic target for neurodevelopmental disorders such as idiopathic autism, attention deficit hyperactivity disorder and Rett syndrome.
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Affiliation(s)
- Nicole M Fisher
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - Robert W Gould
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - Rocco G Gogliotti
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - Annalise J McDonald
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - Hana Badivuku
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - Susmita Chennareddy
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - Aditi B Buch
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - Annah M Moore
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA
| | - Matthew T Jenkins
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - W Hudson Robb
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA
| | - Craig W Lindsley
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA.,Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA
| | - Carrie K Jones
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - P Jeffrey Conn
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Colleen M Niswender
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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47
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Marafi D, Mitani T, Isikay S, Hertecant J, Almannai M, Manickam K, Abou Jamra R, El-Hattab AW, Rajah J, Fatih JM, Du H, Karaca E, Bayram Y, Punetha J, Rosenfeld JA, Jhangiani SN, Boerwinkle E, Akdemir ZC, Erdin S, Hunter JV, Gibbs RA, Pehlivan D, Posey JE, Lupski JR. Biallelic GRM7 variants cause epilepsy, microcephaly, and cerebral atrophy. Ann Clin Transl Neurol 2020; 7:610-627. [PMID: 32286009 PMCID: PMC7261753 DOI: 10.1002/acn3.51003] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 02/10/2020] [Accepted: 02/11/2020] [Indexed: 01/29/2023] Open
Abstract
Objective Defects in ion channels and neurotransmitter receptors are implicated in developmental and epileptic encephalopathy (DEE). Metabotropic glutamate receptor 7 (mGluR7), encoded by GRM7, is a presynaptic G‐protein‐coupled glutamate receptor critical for synaptic transmission. We previously proposed GRM7 as a candidate disease gene in two families with neurodevelopmental disorders (NDDs). One additional family has been published since. Here, we describe three additional families with GRM7 biallelic variants and deeply characterize the associated clinical neurological and electrophysiological phenotype and molecular data in 11 affected individuals from six unrelated families. Methods Exome sequencing and family‐based rare variant analyses on a cohort of 220 consanguineous families with NDDs revealed three families with GRM7 biallelic variants; three additional families were identified through literature search and collaboration with a clinical molecular laboratory. Results We compared the observed clinical features and variants of 11 affected individuals from the six unrelated families. Identified novel deleterious variants included two homozygous missense variants (c.2671G>A:p.Glu891Lys and c.1973G>A:p.Arg685Gln) and one homozygous stop‐gain variant (c.1975C>T:p.Arg659Ter). Developmental delay, neonatal‐ or infantile‐onset epilepsy, and microcephaly were universal. Three individuals had hypothalamic–pituitary–axis dysfunction without pituitary structural abnormality. Neuroimaging showed cerebral atrophy and hypomyelination in a majority of cases. Two siblings demonstrated progressive loss of myelination by 2 years in both and an acquired microcephaly pattern in one. Five individuals died in early or late childhood. Conclusion Detailed clinical characterization of 11 individuals from six unrelated families demonstrates that rare biallelic GRM7 pathogenic variants can cause DEEs, microcephaly, hypomyelination, and cerebral atrophy.
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Affiliation(s)
- Dana Marafi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030.,Department of Pediatrics, Faculty of Medicine, Kuwait University, P.O. Box 24923, 13110, Safat, Kuwait
| | - Tadahiro Mitani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - Sedat Isikay
- Department of Physiotherapy and Rehabilitation, School of Health Sciences, Hasan Kalyoncu University, Gaziantep, 27000, Turkey
| | - Jozef Hertecant
- Pediatric Metabolic and Genetics Division, Tawam Hospital, Al Ain, Abu Dhabi, United Arab Emirates
| | - Mohammed Almannai
- Section of Medical Genetics, Children's Hospital, King Fahad Medical City, Riyadh, 11525, Saudi Arabia
| | - Kandamurugu Manickam
- Division of Genetic and Genomic Medicine, Nationwide Children's Hospital, Columbus, Ohio
| | - Rami Abou Jamra
- Institute of Human Genetics, University Medical Center Leipzig, 04103, Leipzig, Germany
| | - Ayman W El-Hattab
- Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, 27272, United Arab Emirates
| | - Jaishen Rajah
- Sheikh Khalifa Medical City (SKMC), P.O. Box: 51900, Abu Dhabi, United Arab Emirates
| | - Jawid M Fatih
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - Haowei Du
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - Ender Karaca
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - Yavuz Bayram
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - Jaya Punetha
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - Jill A Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - Shalini N Jhangiani
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, 77030
| | - Eric Boerwinkle
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, 77030.,Human Genetics Center, University of Texas Health Science Center at Houston, Houston, Texas
| | - Zeynep C Akdemir
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - Serkan Erdin
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts
| | - Jill V Hunter
- Texas Children's Hospital, Houston, Texas, 77030.,Department of Radiology, Baylor College of Medicine, Houston, Texas, 77030
| | - Richard A Gibbs
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030.,Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, 77030
| | - Davut Pehlivan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030.,Texas Children's Hospital, Houston, Texas, 77030.,Section of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, 77030
| | - Jennifer E Posey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030.,Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, 77030.,Texas Children's Hospital, Houston, Texas, 77030.,Department of Pediatrics, Baylor College of Medicine, Houston, Texas, 77030
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Eaton A, Hartley T, Kernohan K, Ito Y, Lamont R, Parboosingh J, Barrowman N, Innes AM, Boycott K. When to think outside the autozygome: Best practices for exome sequencing in "consanguineous" families. Clin Genet 2020; 97:835-843. [PMID: 32162313 DOI: 10.1111/cge.13736] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 02/15/2020] [Accepted: 03/09/2020] [Indexed: 12/14/2022]
Abstract
Exome sequencing (ES) is an effective diagnostic tool with a high yield in consanguineous families. However, how diagnostic yield and mode of inheritance relate to family structure has not been well delineated. We reviewed ES results from families enrolled in the Care4Rare Canada research consortium with various degrees of consanguinity. We contrasted the diagnostic yield in families with parents who are second cousins or closer ("close" consanguinity) vs those more distantly related or from isolated populations ("presumed" consanguinity). We further stratified by number of affected individuals (multiple affected ["multiplex"] vs single affected [simplex]). The overall yield in 116 families was 45.7% (n = 53) with no significant difference between subgroups. Homozygous variants accounted for 100% and 75% of diagnoses in close and presumed consanguineous multiplex families, respectively. In simplex presumed consanguineous families, a striking 46.2% of diagnoses were due to de novo variants, vs only 11.8% in simplex closely consanguineous families (88.2% homozygous). Our data underscores the high yield of ES in consanguineous families and highlights that while a singleton approach may frequently be reasonable and a responsible use of resources, trio sequencing should be strongly considered in simplex families in the absence of confirmed consanguinity given the proportion of de novo variants.
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Affiliation(s)
- Alison Eaton
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Taila Hartley
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Kristin Kernohan
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada.,Newborn Screening Ontario, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - Yoko Ito
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - Ryan Lamont
- Alberta Children's Hospital Research Institute, Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jillian Parboosingh
- Alberta Children's Hospital Research Institute, Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Nick Barrowman
- Clinical Research Unit, Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
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- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
| | - A Micheil Innes
- Alberta Children's Hospital Research Institute, Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Kym Boycott
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
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49
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Genome-Wide Sequencing for Unexplained Developmental Disabilities or Multiple Congenital Anomalies: A Health Technology Assessment. ONTARIO HEALTH TECHNOLOGY ASSESSMENT SERIES 2020; 20:1-178. [PMID: 32194879 PMCID: PMC7080457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
BACKGROUND People with unexplained developmental disabilities or multiple congenital anomalies might have had many biochemical, metabolic, and genetic tests for a period of years without receiving a diagnosis. A genetic diagnosis can help these people and their families better understand their condition and may help them to connect with others who have the same condition. Ontario Health (Quality), in collaboration with the Canadian Agency for Drugs and Technologies in Health (CADTH) conducted a health technology assessment about the use of genome-wide sequencing for patients with unexplained developmental disabilities or multiple congenital anomalies. Ontario Health (Quality) evaluated the effectiveness, cost-effectiveness, and budget impact of publicly funding genome-wide sequencing. We also conducted interviews with patients and examined the quantitative evidence of preferences and values literature to better understand the patient preferences and values for these tests. METHODS Ontario Health (Quality) performed a systematic literature search of the clinical evidence. We assessed the risk of bias of each included study using the Risk of Bias Assessment tool for Non-randomized Studies (RoBANS) and the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We also performed a search of the quantitative evidence and undertook direct patient engagement to ascertain patient preferences for genetic testing for unexplained developmental disabilities or multiple congenital anomalies. CADTH performed a review of qualitative literature about patient perspectives and experiences, and a review of ethical issues.Ontario Health (Quality) performed an economic literature review of genome-wide sequencing in people with unexplained developmental disabilities or multiple congenital anomalies. Although we found eight published cost-effectiveness studies, none completely addressed our research question. Therefore, we conducted a primary economic evaluation using a discrete event simulation model. Owing to its high cost and early stage of clinical implementation, whole exome sequencing is primarily used for people who do not have a diagnosis from standard testing (referred to here as whole exome sequencing after standard testing; standard testing includes chromosomal microarray and targeted single-gene tests or gene panels). Therefore, in our first analysis, we evaluated the cost-effectiveness of whole exome sequencing after standard testing versus standard testing alone. In our second analysis, we explored the cost-effectiveness of whole exome and whole genome sequencing used at various times in the diagnostic pathway (e.g., first tier, second tier, after standard testing) versus standard testing. We also estimated the budget impact of publicly funding genome-wide sequencing in Ontario for the next 5 years. RESULTS Forty-four studies were included in the clinical evidence review. The overall diagnostic yield of genome-wide sequencing for people with unexplained development disability and multiple congenital anomalies was 37%, but we are very uncertain about this estimate (GRADE: Very Low). Compared with standard genetic testing of chromosomal microarray and targeted single-gene tests or gene panels, genome-wide sequencing could have a higher diagnostic yield (GRADE: Low). As well, for some who are tested, genome-wide sequencing prompts some changes to medications, treatments, and referrals to specialists (GRADE: Very Low).Whole exome sequencing after standard testing cost an additional $3,261 per patient but was more effective than standard testing alone. For every 1,000 persons tested, using whole exome sequencing after standard testing would lead to an additional 240 persons with a molecular diagnosis, 272 persons with any positive finding, and 46 persons with active treatment change (modifications to medications, procedures, or treatment). The resulting incremental cost-effectiveness ratios (ICERs) were $13,591 per additional molecular diagnosis. The use of genome-wide sequencing early in the diagnostic pathway (e.g., as a first- or second-tier test) can save on costs and improve diagnostic yields over those of standard testing. Results remained robust when parameters and assumptions were varied.Our budget impact analysis showed that, if whole exome sequencing after standard testing continues to be funded through Ontario's Out-of-Country Prior Approval Program, its budget impact would range from $4 to $5 million in years 1 to 5. If whole exome sequencing becomes publicly funded in Ontario (not through the Out-of-Country Prior Approval Program), the budget impact would be about $9 million yearly. We also found that using whole exome sequencing as a second-tier test would lead to cost savings ($3.4 million per 1,000 persons tested yearly).Participants demonstrated consistent motivations for and expectations of obtaining a diagnosis for unexplained developmental delay or congenital anomalies through genome-wide sequencing. Patients and families greatly value the support and information they receive through genetic counselling when considering genome-wide sequencing and learning of a diagnosis. CONCLUSIONS Genome-wide sequencing could have a higher diagnostic yield than standard testing for people with unexplained developmental disabilities or multiple congenital anomalies. Genome-wide sequencing can also prompt some changes to medications, treatments, and referrals to specialists for some people tested; however, we are very uncertain about this. Genome-wide sequencing could be a cost-effective strategy when used after standard testing to diagnose people with unexplained developmental disabilities or multiple congenital anomalies. It could also lead to cost savings when used earlier in the diagnostic pathway. Patients and families consistently noted a benefit from seeking a diagnosis through genetic testing.
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50
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Wang Y, Zhu LN, Ma XW, Yang F, Xu XL, Yang Y, Yang X, Peng W, Zhang WQ, Liang JY, Zhu WD, Jiang TJ, Zhang XL, Feng ZC. Gene-Focused Networks Underlying Phenotypic Convergence in a Systematically Phenotyped Cohort With Heterogeneous Intellectual Disability. Front Bioeng Biotechnol 2020; 8:45. [PMID: 32117926 PMCID: PMC7019181 DOI: 10.3389/fbioe.2020.00045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 01/21/2020] [Indexed: 11/13/2022] Open
Abstract
The broad spectrum of intellectual disability (ID) patients' clinical manifestations, the heterogeneity of ID genetic variation, and the diversity of the phenotypic variation represent major challenges for ID diagnosis. By exploiting a manually curated systematic phenotyping cohort of 3803 patients harboring ID, we identified 704 pathogenic genes, 3848 pathogenic sites, and 2075 standard phenotypes for underlying molecular perturbations and their phenotypic impact. We found the positive correlation between the number of phenotypes and that of patients that revealed their extreme heterogeneities, and the relative contribution of multiple determinants to the heterogeneity of ID phenotypes. Nevertheless, despite the extreme heterogeneity in phenotypes, the ID genes had a specific bias of mutation types, and the top 44 genes that ranked by the number of patients accounted for 39.9% of total patients. More interesting, enriched co-occurrent phenotypes and co-occurrent phenotype networks for each gene had the potential for prioritizing ID genes, further exhibited the convergences of ID phenotypes. Then we established a predictor called IDpred using machine learning methods for ID pathogenic genes prediction. Using10-fold cross-validation, our evaluation shows remarkable AUC values for IDpred (auc = 0.978), demonstrating the robustness and reliability of our tool. Besides, we built the most comprehensive database of ID phenotyped cohort to date: IDminer http://218.4.234.74:3100/IDminer/, which included the curated ID data and integrated IDpred tool for both clinical and experimental researchers. The IDminer serves as an important resource and user-friendly interface to help researchers investigate ID data, and provide important implications for the diagnosis and pathogenesis of developmental disorders of cognition.
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Affiliation(s)
- Yan Wang
- BaYi Children’s Hospital, The Seventh Medical Center of PLA General Hospital, Beijing, China
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing, China
- Beijing Key Laboratory of Pediatric Organ Failure, Beijing, China
| | - Li-Na Zhu
- BaYi Children’s Hospital, The Seventh Medical Center of PLA General Hospital, Beijing, China
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing, China
- Beijing Key Laboratory of Pediatric Organ Failure, Beijing, China
| | - Xiu-Wei Ma
- BaYi Children’s Hospital, The Seventh Medical Center of PLA General Hospital, Beijing, China
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing, China
- Beijing Key Laboratory of Pediatric Organ Failure, Beijing, China
| | - Fang Yang
- Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences, Suzhou, China
| | - Xi-Lin Xu
- Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences, Suzhou, China
| | - Yao Yang
- BaYi Children’s Hospital, The Seventh Medical Center of PLA General Hospital, Beijing, China
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing, China
- Beijing Key Laboratory of Pediatric Organ Failure, Beijing, China
| | - Xiao Yang
- BaYi Children’s Hospital, The Seventh Medical Center of PLA General Hospital, Beijing, China
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing, China
- Beijing Key Laboratory of Pediatric Organ Failure, Beijing, China
| | - Wei Peng
- BaYi Children’s Hospital, The Seventh Medical Center of PLA General Hospital, Beijing, China
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing, China
- Beijing Key Laboratory of Pediatric Organ Failure, Beijing, China
| | - Wan-Qiao Zhang
- BaYi Children’s Hospital, The Seventh Medical Center of PLA General Hospital, Beijing, China
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing, China
- Beijing Key Laboratory of Pediatric Organ Failure, Beijing, China
| | - Jin-Yu Liang
- The Second People’s Hospital of Aohanqi, Inner Mongolia, China
| | - Wei-Dong Zhu
- The Second People’s Hospital of Aohanqi, Inner Mongolia, China
| | - Tai-Jiao Jiang
- Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences, Suzhou, China
- Center of Systems Medicine, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xin-Lei Zhang
- Suzhou Geneworks Technology Co., Ltd., Suzhou, China
| | - Zhi-Chun Feng
- BaYi Children’s Hospital, The Seventh Medical Center of PLA General Hospital, Beijing, China
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing, China
- Beijing Key Laboratory of Pediatric Organ Failure, Beijing, China
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