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Montillot C, Skutunova E, Ayushma, Dubied M, Lahmar A, Nguyen S, Peerally B, Prin F, Duffourd Y, Thauvin-Robinet C, Duplomb L, Wang H, Ansar M, Faivre L, Navarro N, Minocha S, Collins SC, Yalcin B. Characterization of Vps13b-mutant mice reveals neuroanatomical and behavioral phenotypes with females less affected. Neurobiol Dis 2023; 185:106259. [PMID: 37573958 DOI: 10.1016/j.nbd.2023.106259] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/26/2023] [Accepted: 08/11/2023] [Indexed: 08/15/2023] Open
Abstract
The vacuolar protein sorting-associated protein 13B (VPS13B) is a large and highly conserved protein. Disruption of VPS13B causes the autosomal recessive Cohen syndrome, a rare disorder characterized by microcephaly and intellectual disability among other features, including developmental delay, hypotonia, and friendly-personality. However, the underlying mechanisms by which VPS13B disruption leads to brain dysfunction still remain unexplained. To gain insights into the neuropathogenesis of Cohen syndrome, we systematically characterized brain changes in Vps13b-mutant mice and compared murine findings to 235 previously published and 17 new patients diagnosed with VPS13B-related Cohen syndrome. We showed that Vps13b is differentially expressed across brain regions with the highest expression in the cerebellum, the hippocampus and the cortex with postnatal peak. Half of the Vps13b-/- mice die during the first week of life. The remaining mice have a normal lifespan and display the core phenotypes of the human disease, including microcephaly, growth delay, hypotonia, altered memory, and enhanced sociability. Systematic 2D and 3D brain histo-morphological analyses reveal specific structural changes in the brain starting after birth. The dentate gyrus is the brain region with the most prominent reduction in size, while the motor cortex is specifically thinner in layer VI. The fornix, the fasciculus retroflexus, and the cingulate cortex remain unaffected. Interestingly, these neuroanatomical changes implicate an increase of neuronal death during infantile stages with no progression in adulthood suggesting that VPS13B promotes neuronal survival early in life. Importantly, whilst both sexes were affected, some neuroanatomical and behavioral phenotypes were less pronounced or even absent in females. We evaluate sex differences in Cohen patients and conclude that females are less affected both in mice and patients. Our findings provide new insights about the neurobiology of VPS13B and highlight previously unreported brain phenotypes while defining Cohen syndrome as a likely new entity of non-progressive infantile neurodegeneration.
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Affiliation(s)
- Charlotte Montillot
- Université de Bourgogne, 21000 Dijon, France; Inserm Unit 1231, 21000 Dijon, France
| | - Emilia Skutunova
- Université de Bourgogne, 21000 Dijon, France; Inserm Unit 1231, 21000 Dijon, France
| | - Ayushma
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi (IITD), Hauz Khas, New Delhi 110016, India
| | - Morgane Dubied
- Biogéosciences, UMR 6282 CNRS, EPHE, Université de Bourgogne, 21000 Dijon, France
| | - Adam Lahmar
- Université de Bourgogne, 21000 Dijon, France; Inserm Unit 1231, 21000 Dijon, France
| | - Sylvie Nguyen
- Université de Bourgogne, 21000 Dijon, France; Inserm Unit 1231, 21000 Dijon, France
| | - Benazir Peerally
- Université de Bourgogne, 21000 Dijon, France; Inserm Unit 1231, 21000 Dijon, France
| | - Fabrice Prin
- Crick Advanced Light Microscopy Facility, The Francis Crick Institute, London NW1 1AT, UK
| | - Yannis Duffourd
- Université de Bourgogne, 21000 Dijon, France; Inserm Unit 1231, 21000 Dijon, France; Unité Fonctionnelle Innovation en Diagnostic génomique des maladies rares, FHU-TRANSLAD, Dijon University Hospital, 21000 Dijon, France
| | - Christel Thauvin-Robinet
- Université de Bourgogne, 21000 Dijon, France; Inserm Unit 1231, 21000 Dijon, France; Unité Fonctionnelle Innovation en Diagnostic génomique des maladies rares, FHU-TRANSLAD, Dijon University Hospital, 21000 Dijon, France; Reference Center for Rare Diseases "Déficiences intellectuelles de causes rares", Dijon University Hospital, 21000 Dijon, France
| | - Laurence Duplomb
- Université de Bourgogne, 21000 Dijon, France; Inserm Unit 1231, 21000 Dijon, France
| | - Heng Wang
- DDC Clinic for Special Needs Children, Middlefield, OH 44062, USA
| | - Muhammad Ansar
- Jules Gonin Eye Hospital, University of Lausanne, CH-1015 Lausanne, Switzerland; Advanced Molecular Genetics and Genomics Disease Research and Treatment Centre, Dow University of Health Sciences, Karachi, Pakistan
| | - Laurence Faivre
- Université de Bourgogne, 21000 Dijon, France; Inserm Unit 1231, 21000 Dijon, France; Reference Center for Rare Diseases "Anomalies du Développement et syndromes malformatifs", Dijon University Hospital, 21000 Dijon, France
| | - Nicolas Navarro
- Biogéosciences, UMR 6282 CNRS, EPHE, Université de Bourgogne, 21000 Dijon, France; EPHE, PSL University, Paris 75014, France
| | - Shilpi Minocha
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi (IITD), Hauz Khas, New Delhi 110016, India
| | - Stephan C Collins
- Université de Bourgogne, 21000 Dijon, France; Inserm Unit 1231, 21000 Dijon, France
| | - Binnaz Yalcin
- Université de Bourgogne, 21000 Dijon, France; Inserm Unit 1231, 21000 Dijon, France.
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AbdelAleem A, Haddad N, Al-Ettribi G, Crunk A, Elsotouhy A. Cohen syndrome and early-onset epileptic encephalopathy in male triplets: two disease-causing mutations in VPS13B and NAPB. Neurogenetics 2023; 24:103-112. [PMID: 36780047 PMCID: PMC10063482 DOI: 10.1007/s10048-023-00710-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 01/07/2023] [Indexed: 02/14/2023]
Abstract
Cohen syndrome (CS) is a rare multisystem autosomal recessive disorder associated with mutations in VPS13B (vacuolar protein sorting homolog 13B). The NAPB-related neurodevelopmental disorder is characterized mainly by early-onset epileptic encephalopathy (EOEE) and is associated with mutations in NAPB that encodes for SNAP-beta (soluble NSF attachment protein beta). Here we describe male triplets, clinically presenting with the phenotype of subtle but distinctive facial features, intellectual disability, increased body weight, neonatal EOEE, and prominently variable abnormal behaviors of autism and sexual arousal. The EEG showed multifocal epilepsy, while the brain MRI showed no abnormalities. Diagnostic exome sequencing (ES), the applied next-generation sequencing approach, revealed the interesting finding of two novel homozygous variants in two genes: VPS13B missense variant (c.8516G > A) and NAPB splice-site loss (c.354 + 2 T > G). Sanger sequencing verified the segregation of the two recessive gene variants with the phenotype in family members. The prediction algorithms support the pathogenicity of these variants. Homozygosity mapping of ES data of this consanguineous family revealed multiple chromosomal regions of homozygosity stretches with the residing of VPS13B (chr8: 100830758G > A) and NAPB (Chr20: 23,375,774 A > C) variants within the largest homozygous blocks further supporting the disease-genes causal role. Interestingly, the functions of the two proteins; VPS13B, a transmembrane protein involved in intracellular protein transport, and SNAP-beta involved in neurotransmitters release at the neuronal synaptic complexes, have been associated with Golgi-mediated vesicular trafficking. Our ES findings provide new insights into the pathologic mechanism underlying the expansion of the neurodevelopmental spectrum in CS and further highlight the importance of Golgi and Golgi-membrane-related proteins in the development of neurodevelopmental syndromes associated with early-onset non-channelopathy epilepsy. To our knowledge, this is the first report documenting multifocal EOEE in CS patients with the association of a pathogenic NAPB variant.
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Affiliation(s)
- Alice AbdelAleem
- Neurogenetics Research Lab, Weill Cornell Medicine Qatar, Doha, Qatar.
- Clinical Genetics Division (Clinical Privilege), Hamad Medical Corporation, Doha, Qatar.
- Medical Molecular Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt.
| | - Naim Haddad
- Neurology Department, Weill Cornell Medicine Qatar, Doha, Qatar
| | - Ghada Al-Ettribi
- Medical Molecular Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, Egypt
| | | | - Ahmed Elsotouhy
- Neuroradiology Department, Hamad Medical Corporation, Doha, Qatar
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3
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Güneş N, Alkaya DU, Demirbilek V, Yalçınkaya C, Tüysüz B. Early Diagnostic Signs and the Natural History of Typical Findings in Cohen Syndrome. J Pediatr 2023; 252:93-100. [PMID: 36067876 DOI: 10.1016/j.jpeds.2022.08.052] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 07/08/2022] [Accepted: 08/31/2022] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To describe the clinical presentation and long-term clinical features of a molecularly confirmed cohort with Cohen syndrome. STUDY DESIGN Twelve patients with Cohen syndrome aged 0.2-13.9 years from 8 families with a median follow-up of 7 years were enrolled to the study. Genetic analyses were made by VPS13B and whole-exome sequencing analyses. RESULTS Biallelic VPS13B variants, including 3 nonsense, 1 frameshift, and 1 splice-site variant, and a multiexon deletion were detected. Prader-Willi syndrome-like features such as hypotonia, small hands, round face with full cheeks, almond-shaped eyes, and micrognathia were observed in all infantile patients. Beginning from age 4 years, it was noticed that the face gradually elongated and became oval. The typical facial features of Cohen syndrome such as a long face, beak-shaped nose, and open-mouth appearance with prominent upper central incisors became evident at age 9. Other Cohen syndrome features including retinopathy (11/11), neutropenia (11/12), truncal obesity (5/12), and myopia (5/11) were detected at the median ages of 7.8, 7, 7.5, and 5 years, respectively. Eleven patients aged older than 5 years at their last examination had severe speech delay. CONCLUSIONS A differential diagnosis of Cohen syndrome in the infancy should be made with Prader-Willi syndrome, and that the typical facial features for Cohen syndrome is prominent at age 9 years, when retinopathy, neutropenia, and truncal obesity become evident. Moreover, adding the severe speech delay to the diagnostic criteria should be considered.
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Affiliation(s)
- Nilay Güneş
- Department of Pediatric Genetics, Istanbul University-Cerrahpaşa, Cerrahpaşa Medical Faculty, Istanbul, Turkey
| | - Dilek Uludağ Alkaya
- Department of Pediatric Genetics, Istanbul University-Cerrahpaşa, Cerrahpaşa Medical Faculty, Istanbul, Turkey
| | - Veysi Demirbilek
- Department of Neurology, Istanbul University-Cerrahpaşa, Cerrahpaşa Medical Faculty, Istanbul, Turkey
| | - Cengiz Yalçınkaya
- Department of Neurology, Istanbul University-Cerrahpaşa, Cerrahpaşa Medical Faculty, Istanbul, Turkey
| | - Beyhan Tüysüz
- Department of Pediatric Genetics, Istanbul University-Cerrahpaşa, Cerrahpaşa Medical Faculty, Istanbul, Turkey.
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Leterme S, Bastien O, Aiese Cigliano R, Amato A, Michaud M. Phylogenetic and Structural Analyses of VPS13 Proteins in Archaeplastida Reveal Their Complex Evolutionary History in Viridiplantae. CONTACT (THOUSAND OAKS (VENTURA COUNTY, CALIF.)) 2023; 6:25152564231211976. [PMID: 38033810 PMCID: PMC10683392 DOI: 10.1177/25152564231211976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 10/09/2023] [Accepted: 10/18/2023] [Indexed: 12/02/2023]
Abstract
VPS13 is a lipid transfer protein family conserved among Eukaryotes and playing roles in fundamental processes involving vesicular transport and membrane expansion including autophagy and organelle biogenesis. VPS13 folds into a long hydrophobic tunnel, allowing lipid transport, decorated by distinct domains involved in protein localization and regulation. Whereas VPS13 organization and function have been extensively studied in yeast and mammals, information in organisms originating from primary endosymbiosis is scarce. In the higher plant Arabidopsis thaliana, four paralogs, AtVPS13S, X, M1, and M2, were identified, AtVPS13S playing a role in the regulation of root growth, cell patterning, and reproduction. In this work, we performed phylogenetic, as well as domain and structural modeling of VPS13 proteins in Archaeplastida in order to understand their general organization and evolutionary history. We confirmed the presence of human VPS13B orthologues in some phyla and described two new VPS13 families presenting a particular domain arrangement: VPS13R in Rhodophytes and VPS13Y in Chlorophytes and Streptophytes. By focusing on Viridiplantae, we were able to draw the evolutionary history of these proteins made by multiple gene gains and duplications as well as domain rearrangements. We showed that some Chlorophytes have only three (AtVPS13M, S, Y) whereas some Charophytes have up to six VPS13 paralogs (AtVPS13M1, M2, S, Y, X, B). We also highlighted specific structural features of VPS13M and X paralogs. This study reveals the complex evolution of VPS13 family and opens important perspectives for their functional characterization in photosynthetic organisms.
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Affiliation(s)
- Sébastien Leterme
- Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG, LPCV, Grenoble, France
| | - Olivier Bastien
- Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG, LPCV, Grenoble, France
| | | | - Alberto Amato
- Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG, LPCV, Grenoble, France
| | - Morgane Michaud
- Université Grenoble Alpes, CNRS, CEA, INRAE, IRIG, LPCV, Grenoble, France
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Kang L, Ma Y, Zhao P. Deletion as novel variants in VPS13B gene in Cohen syndrome: Case series. Transl Neurosci 2023; 14:20220304. [PMID: 37692084 PMCID: PMC10487392 DOI: 10.1515/tnsci-2022-0304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/29/2023] [Accepted: 08/10/2023] [Indexed: 09/12/2023] Open
Abstract
Background Cohen syndrome (OMIM No. # 216550) is a rare autosomal recessive disorder caused by homozygous mutation in the vacuolar protein sorting 13 homolog B (VPS13B) gene on chromosome 8q22.2. Clinical manifestations include hypermobile joints, microcephaly, intellectual disabilities, craniofacial and limb anomalies, and neutropenia. To date, more than 200 mutations of VPS13B have been reported in over 1,000 Cohen syndrome patients. This article reviews the clinical data of two cases of Cohen syndrome diagnosed by whole exome sequencing. Results Both children visited for psychomotor retardation. Gene detection showed a mutation in 8q22.2, NM_017890.4 Intron38 c.6940+1G > T and heterozygotic deletion of exon 3-19 of the VPS13B gene (Case 1), and a mutation in 8q22.2, NM_017890.4 Intron38 c.6940+1G > T and 8q22, NM_017890.4 Exon56 c10334_10335del in the VPS13B gene (Case 2). The variation was predicted to be pathogenic by related software, and they have not been reported. Conclusion Cohen syndrome should be considered in the differential diagnosis of any child with developmental retardation and neutropenia. The present study increases the mutation spectrum of the VPS13B gene and could be helpful in genetic diagnosis and genetic counseling in Cohen syndrome patients.
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Affiliation(s)
- Li Kang
- Department of Rehabilitation Medicine, Tianjin Children’s Hospital, 238 Longyan Road, Rui Jing District, Tianjin, 300134, China
| | - Yixuan Ma
- Division of Sports Science and Physical Education, Tsinghua University, Beijing100081, China
| | - Peng Zhao
- Department of Rehabilitation Medicine, Tianjin Children’s Hospital, 238 Longyan Road, Rui Jing District, Tianjin, 300134, China
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Quantitative trait locus analysis for endophenotypes reveals genetic substrates of core symptom domains and neurocognitive function in autism spectrum disorder. Transl Psychiatry 2022; 12:407. [PMID: 36153334 PMCID: PMC9509384 DOI: 10.1038/s41398-022-02179-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 09/08/2022] [Accepted: 09/12/2022] [Indexed: 11/25/2022] Open
Abstract
Autism spectrum disorder (ASD) represents a heterogeneous group of neurodevelopmental disorders and is largely attributable to genetic risk factors. Phenotypic and genetic heterogeneity of ASD have been well-recognized; however, genetic substrates for endophenotypes that constitute phenotypic heterogeneity are not yet known. In the present study, we compiled data from the Autism Genetic Resource Exchange, which contains the demographic and detailed phenotype information of 11,961 individuals. Notably, the whole-genome sequencing data available from MSSNG and iHART for 3833 individuals in this dataset was used to perform an endophenotype-wide association study. Using a linear mixed model, genome-wide association analyses were performed for 29 endophenotype scores and 0.58 million common variants with variant allele frequency ≥ 5%. We discovered significant associations between 9 genetic variants and 6 endophenotype scores comprising neurocognitive development and severity scores for core symptoms of ASD at a significance threshold of p < 5 × 10-7. Of note, the Stereotyped Behaviors and Restricted Interests total score in Autism Diagnostic Observation Schedule Module 3 was significantly associated with multiple variants in the VPS13B gene, a causal gene for Cohen syndrome and a candidate gene for syndromic ASD. Our findings yielded loci with small effect sizes due to the moderate sample size and, thus, require validation in another cohort. Nonetheless, our endophenotype-wide association analysis extends previous candidate gene discovery in the context of genotype and endophenotype association. As a result, these candidate genes may be responsible for specific traits that constitute core symptoms and neurocognitive function of ASD rather than the disorder itself.
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Kehinde TA, Bhatia A, Olarewaju B, Shoaib MZ, Mousa J, Osundiji MA. Syndromic obesity with neurodevelopmental delay: Opportunities for targeted interventions. Eur J Med Genet 2022; 65:104443. [DOI: 10.1016/j.ejmg.2022.104443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 01/09/2022] [Accepted: 01/22/2022] [Indexed: 01/01/2023]
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Tarani L, Rasio D, Tarani F, Parlapiano G, Valentini D, Dylag KA, Spalice A, Paparella R, Fiore M. Pediatrics for Disability: A Comprehensive Approach to Children with Syndromic Psychomotor Delay. Curr Pediatr Rev 2022; 18:110-120. [PMID: 34844545 DOI: 10.2174/1573396317666211129093426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 06/30/2021] [Accepted: 09/21/2021] [Indexed: 11/22/2022]
Abstract
Intellectual disability is the impairment of cognitive, linguistic, motor and social skills that occurs in the pediatric age and is also described by the term "mental retardation". Intellectual disability occurs in 3-28 % of the general population due to a genetic cause, including chromosome aberrations. Among people with intellectual disabilities, the cause of the disability was identified as a single gene disorder in up to 12 %, multifactorial disorders in up to 4 %, and genetic disorders in up to 8.5 %. Children affected by a malformation syndrome associated with mental retardation or intellectual disability represent a care challenge for the pediatrician. A multidisciplinary team is essential to manage the patient, thereby controlling the complications of the syndrome and promoting the correct psychophysical development. This requires continuous follow-up of these children by the pediatrician, which is essential for both the clinical management of the syndrome and facilitating the social integration of these children.
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Affiliation(s)
- Luigi Tarani
- Department of Pediatrics, Medical Faculty, Sapienza University of Rome, Rome, Italy
| | - Debora Rasio
- Department of Pediatry, Sarn Raffaele Hospital, Rome, Italy
| | - Francesca Tarani
- Department of Pediatrics, Medical Faculty, Sapienza University of Rome, Rome, Italy
| | - Giovanni Parlapiano
- Department of Pediatrics, Medical Faculty, Sapienza University of Rome, Rome, Italy
| | | | - Katarzyna Anna Dylag
- Department of Pediatric Nephrology, Jagiellonian University Medical College, Krakow, Poland.,St. Louis Children Hospital, Krakow, Poland
| | - Alberto Spalice
- Department of Pediatrics, Medical Faculty, Sapienza University of Rome, Rome, Italy
| | - Roberto Paparella
- Department of Pediatrics, Medical Faculty, Sapienza University of Rome, Rome, Italy
| | - Marco Fiore
- Institute of Biochemistry and Cell Biology, IBBC-CNR, Rome, Italy
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Vacuolar Protein-Sorting Receptor MoVps13 Regulates Conidiation and Pathogenicity in Rice Blast Fungus Magnaporthe oryzae. J Fungi (Basel) 2021; 7:jof7121084. [PMID: 34947066 PMCID: PMC8708568 DOI: 10.3390/jof7121084] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/04/2021] [Accepted: 12/16/2021] [Indexed: 01/18/2023] Open
Abstract
Magnaporthe oryzae (synonym Pyricularia oryzae) is a filamentous fungal pathogen that causes major yield losses in cultivated rice worldwide. However, the mechanisms of infection of M. oryzae are not well characterized. The VPS13 proteins play vital roles in various biological processes in many eukaryotic organisms, including in the organization of actin cytoskeleton, vesicle trafficking, mitochondrial fusion, and phagocytosis. Nevertheless, the function of the Vps13 protein in plant pathogenic fungi has not been explored. Here, we analysed the biological functions of the Vps13 protein in the development and pathogenicity of M. oryzae. Deletion mutants of MoVps13 significantly reduced the conidiation and decreased the rate of fungal infection on hosts. Moreover, the loss of MoVps13 resulted in defective cell wall integrity (CWI) and plasma membrane (PM) homeostasis when treated with chemicals for inducing cell wall stress (200 mg/mL Congo Red or 0.005% SDS) and sphingolipid synthesis inhibitors (2 μM myriocin or 2 μM amphotericin B). This indicated that MoVps13 is also involved in cell wall synthesis and sphingolipid synthesis. Through immunoblotting, autophagic flux detection, co-localization, and chemical drug sensitivity assays, we confirmed the involvement of Movps13 in ER-phagy and the response to ER stress. Additionally, we generated the C-terminal structure of MoVps13 with high accuracy using the alphaflod2 database. Our experimental evidence indicates that MoVps13 is an important virulence factor that regulates the pathogenicity of M. oryzae by controlling CWI, lipid metabolism and the ER-phagy pathway. These results have expanded our knowledge about pathogenic fungi and will help exploration for novel therapeutic strategies against the rice blast fungus.
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Daich Varela M, Motta FL, Webster AR, Arno G. A rare canonical splice-site variant in VPS13B causes attenuated Cohen syndrome. Ophthalmic Genet 2021; 43:110-115. [PMID: 34425733 DOI: 10.1080/13816810.2021.1970194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND To describe a patient with a history of obesity, retinal dystrophy, type II diabetes, and mild cognitive impairment; found to harbour biallelic splice-site variants in VPS13B. MATERIALS & METHODS A complete ophthalmic evaluation was performed at Moorfields Eye Hospital (London, United Kingdom), consisting of measurement of best-corrected visual acuity (BCVA), slit lamp and dilated fundus evaluation, colour, autofluorescence and near-infrared retinal imaging, spectral domain-optical coherence tomography, and electroretinogram (ERG). Whole-genome sequencing was performed as part of the UK's 100,000 Genomes Project. RESULTS A 26-year-old Pakistani man with normal appearance, stature, and head size presented with decreased BCVA and severely constricted visual fields to our Ophthalmic Genetics clinic. He had a history of obesity, type II diabetes, and mild cognitive impairment. His evaluation showed retina-wide, severe photoreceptor dysfunction in both eyes, with undetectable scotopic and photopic ERG waveforms. Genomic analysis identified a homozygous rare splice donor variant in the VPS13B gene (c.5024+2T>C) that was demonstrated to lead to skipping of the in-frame exon 31 (p.Gln1607_Ser1675delinsHis). CONCLUSIONS Exon 31 skipping in VPS13B may lead to a hypomorphic change, with partial gene function and an incomplete, mild Cohen syndrome-like phenotype.
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Affiliation(s)
- Malena Daich Varela
- UCL Institute of Ophthalmology, London, UK.,Moorfields Eye Hospital, London, UK
| | - Fabiana Louise Motta
- UCL Institute of Ophthalmology, London, UK.,Department of Ophthalmology, Universidade Federal de Sao Paulo, Sao Paulo, Brazil
| | - Andrew R Webster
- UCL Institute of Ophthalmology, London, UK.,Moorfields Eye Hospital, London, UK
| | - Gavin Arno
- UCL Institute of Ophthalmology, London, UK.,Moorfields Eye Hospital, London, UK.,North Thames Genomic Laboratory Hub, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
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11
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Karimzadeh MR, Omidi F, Sahebalzamani A, Saeidi K. A Novel VPS13B Mutation Identified by Whole-Exome Sequencing in Iranian Patients with Cohen Syndrome. J Mol Neurosci 2021; 71:2566-2574. [PMID: 34041686 DOI: 10.1007/s12031-021-01852-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 04/26/2021] [Indexed: 11/27/2022]
Abstract
Cohen syndrome is caused by homozygous mutation in the vacuolar protein sorting 13 homolog B (VPS13B, also referred to as COH1) gene on chromosome 8q22.2. The VPS13B protein is involved in transmembrane transport, Golgi integrity, and neuritogenesis. Clinical manifestations of Cohen syndrome are mainly intellectual disability, developmental delay, facial abnormalities, and eye disorders. This study aimed to identify the causative variant in two unrelated families with Cohen syndrome. To this end, whole-exome sequencing (WES) was performed to identify the pathogenic variants. A homozygous nonsense variant (NM_017890:c.10369C > T; NP_060360.3: p.Q3457X) in the VPS13B gene was identified and co-segregated with all affected individuals in both families. In silico analysis highly suggested this variant as damaging for protein function. The present study increases the mutation spectrum of the VPS13B gene and could be useful in genetic diagnosis and genetic counseling in Cohen syndrome patients.
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Affiliation(s)
- Mohammad Reza Karimzadeh
- Department of Medical Genetics, School of Medicine, Bam University of Medical Sciences, Bam, Iran
| | - Fatemeh Omidi
- Department of Medical Genetics, Afzalipour Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | | | - Kolsoum Saeidi
- Student Research Committee, Kerman University of Medical Sciences, Kerman, Iran.
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Lhussiez V, Dubus E, Cesar Q, Acar N, Nandrot EF, Simonutti M, Audo I, Lizé E, Nguyen S, Geissler A, Bouchot A, Ansar M, Picaud S, Thauvin-Robinet C, Olivier-Faivre L, Duplomb L, Da Costa R. Cohen Syndrome-Associated Cataract Is Explained by VPS13B Functions in Lens Homeostasis and Is Modified by Additional Genetic Factors. Invest Ophthalmol Vis Sci 2021; 61:18. [PMID: 32915983 PMCID: PMC7488618 DOI: 10.1167/iovs.61.11.18] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Purpose Cohen syndrome (CS) is a rare genetic disorder caused by variants of the VPS13B gene. CS patients are affected with a severe form of retinal dystrophy, and in several cases cataracts also develop. The purpose of this study was to investigate the mechanisms and risk factors for cataract in CS, as well as to report on cataract surgeries in CS patients. Methods To understand how VPS13B is associated with visual impairments in CS, we generated the Vps13b∆Ex3/∆Ex3 mouse model. Mice from 1 to 3 months of age were followed by ophthalmoscopy and slit-lamp examinations. Phenotypes were investigated by histology, immunohistochemistry, and western blot. Literature analysis was performed to determine specific characteristic features of cataract in CS and to identify potential genotype–phenotype correlations. Results Cataracts rapidly developed in 2-month-old knockout mice and were present in almost all lenses at 3 months. Eye fundi appeared normal until cataract development. Lens immunostaining revealed that cataract formation was associated with the appearance of large vacuoles in the cortical area, epithelial–mesenchymal transition, and fibrosis. In later stages, cataracts became hypermature, leading to profound retinal remodeling due to inflammatory events. Literature analysis showed that CS-related cataracts display specific features compared to other forms of retinitis pigmentosa-related cataracts, and their onset is modified by additional genetic factors. Corroboratively, we were able to isolate a subline of the Vps13b∆Ex3/∆Ex3 model with delayed cataract onset. Conclusions VPS13B participates in lens homeostasis, and the CS-related cataract development dynamic is linked to additional genetic factors.
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Affiliation(s)
- Vincent Lhussiez
- INSERM UMR1231, Equipe GAD, Université de Bourgogne Franche Comté, Dijon, France
| | - Elisabeth Dubus
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRAE, Université Bourgogne Franche-Comté, Dijon, France
| | - Quénol Cesar
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Niyazi Acar
- Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRAE, Université Bourgogne Franche-Comté, Dijon, France
| | - Emeline F Nandrot
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Manuel Simonutti
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Eléonore Lizé
- INSERM UMR1231, Equipe GAD, Université de Bourgogne Franche Comté, Dijon, France
| | - Sylvie Nguyen
- INSERM UMR1231, Equipe GAD, Université de Bourgogne Franche Comté, Dijon, France
| | - Audrey Geissler
- Plateforme d'Imagerie Cellulaire DImaCell (site CellImaP), INSERM LNC UMR1231, Dijon, France
| | - André Bouchot
- Plateforme d'Imagerie Cellulaire DImaCell (site CellImaP), INSERM LNC UMR1231, Dijon, France
| | - Muhammad Ansar
- Institute of Molecular and Clinical Ophthalmology Basel, Basel, Switzerland.,Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
| | - Serge Picaud
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Christel Thauvin-Robinet
- INSERM UMR1231, Equipe GAD, Université de Bourgogne Franche Comté, Dijon, France.,FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France.,Centre de Référence Déficiences Intellectuelles de Causes Rares, CHU Dijon Bourgogne, Dijon, France
| | - Laurence Olivier-Faivre
- INSERM UMR1231, Equipe GAD, Université de Bourgogne Franche Comté, Dijon, France.,FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France.,Centre de Référence Anomalies du Développement et Syndromes Malformatifs, CHU Dijon Bourgogne, Dijon, France
| | - Laurence Duplomb
- INSERM UMR1231, Equipe GAD, Université de Bourgogne Franche Comté, Dijon, France.,FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France
| | - Romain Da Costa
- INSERM UMR1231, Equipe GAD, Université de Bourgogne Franche Comté, Dijon, France.,FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France
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13
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Lafon A, Faivre L, Seux D, Gautier E, Duplomb L, Grogogeat B, Marcelet A, Laforest L. Periodontal disorders in a cohort of patients with Cohen syndrome. SPECIAL CARE IN DENTISTRY 2020; 41:118-124. [PMID: 33202072 DOI: 10.1111/scd.12544] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 10/01/2020] [Accepted: 10/24/2020] [Indexed: 11/27/2022]
Abstract
AIMS Cohen syndrome (CS) is an uncommon autosomal recessive disorder due to mutations in vacuolar protein sorting 13B, with an intermittent presence of neutropenia. Contrary to other clinical phenotypic features, oral health has been little investigated in CS. We described oral health and dental hygiene in a cohort of CS patients. METHODS AND RESULTS Twelve CS patients with neutropenia (<1500/mm3 ) were recruited in the dental department of Dijon University Hospital (France). Patients underwent oral examination, and blood samples were collected. Oral health markers were described and compared between patients with moderate and severe neutropenia (<500/mm3 ). In 12 patients (mean age = 21.1 years, SD = 13.7, six females), 45.5% brushed at least twice daily their teeth, and the same percentage annually visited a dentist. Dental plaque index was high (mean = 1.7, SD = 1.4). So was the number of lost teeth per patient, notably among adults (mean = 13.8, SD = 9.8). Elevated markers of periodontitis were noted as percentage of bleeding dental sites (mean = 70.2%, SD = 45.2%) or Gingival Index (mean = 2.2, SD = 1.0). The severity of neutropenia was correlated to the level of tooth-loss (P = .03). CONCLUSION This study highlighted in CS patients worrisome oral health and dental follow-up in the context of intellectual disability with behavioural anomalies. More attention is needed by care-givers on oral condition in CS.
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Affiliation(s)
- Arnaud Lafon
- Faculté d'odontologie, Université de Lyon, Université Lyon 1, Lyon, France.,Hospices Civils de Lyon, Service de Consultations et de Traitements Dentaires, Lyon, France.,Enseignant chercheur du Laboratoire Parcours de Santé Systémique EA 4129-Ecole Doctorale EDISS, Université Claude Bernard Lyon 1, Lyon, France
| | - Laurence Faivre
- Inserm UMR1231, Team Génétique des Anomalies du Développement, Université de Bourgogne Franche Comté, Dijon, France.,FHU TRANSLAD, Département de Génétique, CHU Dijon, Université de Bourgogne Franche-Comté, Dijon, France.,Centre de référence Anomalies du Développement et Syndromes Malformatifs, Hôpital d'Enfants, CHU Dijon, Dijon, France
| | - Dominique Seux
- Faculté d'odontologie, Université de Lyon, Université Lyon 1, Lyon, France.,Hospices Civils de Lyon, Service de Consultations et de Traitements Dentaires, Lyon, France.,Université de Lyon, LMI UMR CNRS 5615, Lyon, France
| | - Elodie Gautier
- FHU TRANSLAD, Département de Génétique, CHU Dijon, Université de Bourgogne Franche-Comté, Dijon, France.,Centre de référence Anomalies du Développement et Syndromes Malformatifs, Hôpital d'Enfants, CHU Dijon, Dijon, France
| | - Laurence Duplomb
- Inserm UMR1231, Team Génétique des Anomalies du Développement, Université de Bourgogne Franche Comté, Dijon, France.,FHU TRANSLAD, Département de Génétique, CHU Dijon, Université de Bourgogne Franche-Comté, Dijon, France
| | - Brigitte Grogogeat
- Faculté d'odontologie, Université de Lyon, Université Lyon 1, Lyon, France.,Hospices Civils de Lyon, Service de Consultations et de Traitements Dentaires, Lyon, France.,Université de Lyon, LMI UMR CNRS 5615, Lyon, France
| | | | - Laurent Laforest
- Faculté d'odontologie, Université de Lyon, Université Lyon 1, Lyon, France
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Lee YK, Hwang SK, Lee SK, Yang JE, Kwak JH, Seo H, Ahn H, Lee YS, Kim J, Lim CS, Kaang BK, Lee JH, Lee JA, Lee K. Cohen Syndrome Patient iPSC-Derived Neurospheres and Forebrain-Like Glutamatergic Neurons Reveal Reduced Proliferation of Neural Progenitor Cells and Altered Expression of Synapse Genes. J Clin Med 2020; 9:jcm9061886. [PMID: 32560273 PMCID: PMC7356975 DOI: 10.3390/jcm9061886] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 06/07/2020] [Accepted: 06/15/2020] [Indexed: 12/17/2022] Open
Abstract
Cohen syndrome (CS), a rare autosomal recessive disorder, has been associated with genetic mutations in the VPS13B gene, which regulates vesicle-mediated protein sorting and transport. However, the cellular mechanism underlying CS pathogenesis in patient-derived human neurons remains unknown. We identified a novel compound heterozygous mutation, due to homozygous variation of biparental origin and heterozygous variation inherited from the father, in the VPS13B gene in a 20-month-old female patient. To understand the cellular pathogenic mechanisms, we generated induced pluripotent stem cells (iPSCs) from the fibroblasts of the CS patient. The iPSCs were differentiated into forebrain-like functional glutamatergic neurons or neurospheres. Functional annotation from transcriptomic analysis using CS iPSC-derived neurons revealed that synapse-related functions were enriched among the upregulated and downregulated genes in the CS neurons, whereas processes associated with neurodevelopment were enriched in the downregulated genes. The developing CS neurospheres were small in size compared to control neurospheres, likely due to the reduced proliferation of SOX2-positive neural stem cells. Moreover, the number of SV2B-positive puncta and spine-like structures was significantly reduced in the CS neurons, suggesting synaptic dysfunction. Taking these findings together, for the first time, we report a potential cellular pathogenic mechanism which reveals the alteration of neurodevelopment-related genes and the dysregulation of synaptic function in the human induced neurons differentiated from iPSCs and neurospheres of a CS patient.
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Affiliation(s)
- You-Kyung Lee
- Department of Biotechnology and Biological Sciences, Hannam University, Daejeon 34430, Korea; (Y.-K.L.); (S.-K.L.)
| | - Su-Kyeong Hwang
- Department of Pediatrics, School of Medicine, Kyungpook National University, Daegu 41944, Korea;
| | - Soo-Kyung Lee
- Department of Biotechnology and Biological Sciences, Hannam University, Daejeon 34430, Korea; (Y.-K.L.); (S.-K.L.)
| | - Jung-eun Yang
- Department of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 08826, Korea; (J.-e.Y.); (B.-K.K.)
| | - Ji-Hye Kwak
- Laboratory for Behavioral Neural Circuitry and Physiology, Department of Anatomy, Brain Science & Engineering Institute, School of Medicine, Kyungpook National University, Daegu 41944, Korea; (J.-H.K.); (H.S.)
| | - Hyunhyo Seo
- Laboratory for Behavioral Neural Circuitry and Physiology, Department of Anatomy, Brain Science & Engineering Institute, School of Medicine, Kyungpook National University, Daegu 41944, Korea; (J.-H.K.); (H.S.)
| | - Hyunjun Ahn
- Stem Cell Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea; (H.A.); (J.K.)
- Department of Functional Genomics, KRIBB School of Bioscience, University of Science and Technology, Daejeon 34113, Korea
| | - Yong-Seok Lee
- Department of Physiology, Biomedical Sciences, Neuroscience Research Institute, Seoul National University College of Medicine, Seoul 03080, Korea;
| | - Janghwan Kim
- Stem Cell Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea; (H.A.); (J.K.)
- Department of Functional Genomics, KRIBB School of Bioscience, University of Science and Technology, Daejeon 34113, Korea
| | - Chae-Seok Lim
- Department of Pharmacology, Wonkwang University School of Medicine, Iksan 54538, Korea;
| | - Bong-Kiun Kaang
- Department of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 08826, Korea; (J.-e.Y.); (B.-K.K.)
| | - Jae-Hyung Lee
- Department of Life and Nanopharmaceutical Sciences, Department of Oral Microbiology, School of Dentistry, Kyung Hee University, Seoul 02447, Korea
- Correspondence: (J.-H.L.); (J.-A.L.); (K.L.); Tel.: +82-2-961-9290 (J.H.L); +82 42-629-8785 (J.A.L); +82-53-420-4803 (K.L.)
| | - Jin-A Lee
- Department of Biotechnology and Biological Sciences, Hannam University, Daejeon 34430, Korea; (Y.-K.L.); (S.-K.L.)
- Correspondence: (J.-H.L.); (J.-A.L.); (K.L.); Tel.: +82-2-961-9290 (J.H.L); +82 42-629-8785 (J.A.L); +82-53-420-4803 (K.L.)
| | - Kyungmin Lee
- Laboratory for Behavioral Neural Circuitry and Physiology, Department of Anatomy, Brain Science & Engineering Institute, School of Medicine, Kyungpook National University, Daegu 41944, Korea; (J.-H.K.); (H.S.)
- Correspondence: (J.-H.L.); (J.-A.L.); (K.L.); Tel.: +82-2-961-9290 (J.H.L); +82 42-629-8785 (J.A.L); +82-53-420-4803 (K.L.)
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15
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Nasser F, Kurtenbach A, Biskup S, Weidensee S, Kohl S, Zrenner E. Ophthalmic features of retinitis pigmentosa in Cohen syndrome caused by pathogenic variants in the VPS13B gene. Acta Ophthalmol 2020; 98:e316-e321. [PMID: 31580008 DOI: 10.1111/aos.14255] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 09/06/2019] [Indexed: 11/27/2022]
Abstract
PURPOSE The aim of this study is to report on the phenotype and genotype of five patients diagnosed with Cohen syndrome, an extremely rare autosomal recessive disorder manifesting with mental and physiological defects. METHODS Five patients from three German families and one Syrian family underwent a comprehensive ophthalmological examination. The scheduled visual acuity measurements, fundus ophthalmoscopy, spectral domain optical coherence tomography (OCT), full-field electrophysiological recordings of scotopic and photopic electroretinograms (ERGs) and colour vision testing could not be carried out in all subjects, because of the mental and physical retardation. The genetic diagnosis was achieved by next-generation sequencing. RESULTS The ophthalmic and systemic phenotype of the patients is typical for Cohen syndrome including myopia, night blindness, photophobia, fundus pigmentary changes and bull's eye maculopathy. Electroretinograms (ERGs) were extinguished in the four patients, whose recording was possible. Genetic testing revealed homozygous or two heterozygous bi-allelic mutations in the VPS13B (COH1) gene in all five patients, with five different allelic variants observed. The homozygous mutation c.6055_6056delGA; p.Asp2019Glnfs*15 in two sibling patients as well as the homozygous nonsense mutation c.8112C>G;p.Tyr2704* have not previously been reported. CONCLUSIONS The phenotype of the five patients reported here is typical for Cohen syndrome; however, their genotype is heterogeneous. Two new allelic variants were found to be the causative mutation.
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Affiliation(s)
- Fadi Nasser
- Centre for Ophthalmology University of Tuebingen Tuebingen Germany
| | - Anne Kurtenbach
- Centre for Ophthalmology University of Tuebingen Tuebingen Germany
| | | | | | - Susanne Kohl
- Centre for Ophthalmology University of Tuebingen Tuebingen Germany
| | - Eberhart Zrenner
- Centre for Ophthalmology University of Tuebingen Tuebingen Germany
- Werner Reichardt Centre for Integrative Neuroscience (CIN) University of Tuebingen Tuebingen Germany
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16
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Koehler K, Schuelke M, Hell AK, Schittkowski M, Huebner A, Brockmann K. A novel homozygous nonsense mutation of VPS13B associated with previously unreported features of Cohen syndrome. Am J Med Genet A 2019; 182:570-575. [PMID: 31825161 DOI: 10.1002/ajmg.a.61435] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 10/21/2019] [Accepted: 11/18/2019] [Indexed: 11/10/2022]
Abstract
Cohen syndrome (CS) is a rare autosomal recessive disorder associated with mutations in the vacuolar protein sorting 13 homolog B (VPS13B; formerly COH1) gene. The core clinical phenotype comprises a characteristic facial gestalt, marked developmental delay, and myopia. Additional, nonobligatory features include obesity, microcephaly, short stature, muscular hypotonia, scoliosis, narrow hands and feet, progressive retinopathy, as well as neutropenia. Here we report a novel homozygous nonsense mutation in the VPS13B gene and previously undescribed clinical features in a 19-year-old woman with developmental delay, intellectual disability, and a particular facial appearance. The patient showed several features consistent with CS. In addition, the parents observed congenital alacrima and anhidrosis persisting until onset of puberty. The diagnosis was not established based on the clinical phenotype. We performed whole-genome sequencing and identified a novel homozygous nonsense mutation c.62T>G (NM_152564.4), p.(Leu21*) in the VPS13B gene. Our findings extended the previously reported phenotype of CS. We conclude that transient, prepubertal alacrima and anhidrosis are part of the phenotypic spectrum of CS associated with a novel homozygous nonsense mutation in the VPS13B gene.
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Affiliation(s)
- Katrin Koehler
- Department of Pediatrics, Medizinische Fakultät, Technische Universität Dresden, Dresden, Germany
| | - Markus Schuelke
- Department of Neuropediatrics and NeuroCure Clinical Research Center, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Anna K Hell
- Pediatric Orthopaedics; Department of Trauma, Orthopaedic and Plastic Surgery, University Medical Center Göttingen, Göttingen, Germany
| | - Michael Schittkowski
- Department of Ophthalmology, Section for Strabismus, Neuroophthalmology and Oculoplastics, University Medical Center Göttingen, Göttingen, Germany
| | - Angela Huebner
- Department of Pediatrics, Medizinische Fakultät, Technische Universität Dresden, Dresden, Germany
| | - Knut Brockmann
- Interdisciplinary Pediatric Center for Children with Developmental Disabilities and Severe Chronic Disorders, University Medical Center Göttingen, Göttingen, Germany
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17
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Zhao S, Luo Z, Xiao Z, Li L, Zhao R, Yang Y, Zhong Y. Case report: two novel VPS13B mutations in a Chinese family with Cohen syndrome and hyperlinear palms. BMC MEDICAL GENETICS 2019; 20:187. [PMID: 31752730 PMCID: PMC6873578 DOI: 10.1186/s12881-019-0920-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 11/11/2019] [Indexed: 01/18/2023]
Abstract
BACKGROUND Cohen syndrome (CS) is an uncommon developmental disease with evident clinical heterogeneity. VPS13B is the only gene responsible for CS. Only few sporadic cases of CS have been reported in China. CASE PRESENTATION A Chinese family with two offspring-patients affected by developmental delay and intellectual disability was investigated in this study. Exome sequencing was performed, and compound heterozygous mutations in VPS13B were segregated for family members with autosomal recessive disorder. Splicing mutation c.3666 + 1G > T (exon 24) and nonsense mutation c. 9844 A > T:p.K3282X (exon 54) were novel. We revisited the family and learned that both patients are affected by microcephaly, developmental delay, neutropenia, and myopia and have a friendly disposition, all of which are consistent with CS phenotypes. We also found that both patients have hyperlinear palms, which their parents do not have. VPS13B mutations reported among the Chinese population were reviewed accordingly. CONCLUSIONS This study presents two novel VPS13B mutations in CS. The identification of hyperlinear palms in a family affected by CS expands the phenotype spectrum of CS.
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Affiliation(s)
- Sha Zhao
- The Laboratory of Genetics and Metabolism, Hunan Children's Research Institute (HCRI), Hunan Children's Hospital, University of South China, Changsha, 410007, China.,Department of Child Healthcare, Hunan Children's Hospital, University of South China, Changsha, 410007, Hunan, China
| | - Zhenqing Luo
- The Laboratory of Genetics and Metabolism, Hunan Children's Research Institute (HCRI), Hunan Children's Hospital, University of South China, Changsha, 410007, China
| | - Zhenghui Xiao
- The Laboratory of Genetics and Metabolism, Hunan Children's Research Institute (HCRI), Hunan Children's Hospital, University of South China, Changsha, 410007, China
| | - Liping Li
- The Laboratory of Genetics and Metabolism, Hunan Children's Research Institute (HCRI), Hunan Children's Hospital, University of South China, Changsha, 410007, China
| | - Rui Zhao
- The Laboratory of Genetics and Metabolism, Hunan Children's Research Institute (HCRI), Hunan Children's Hospital, University of South China, Changsha, 410007, China
| | - Yongjia Yang
- The Laboratory of Genetics and Metabolism, Hunan Children's Research Institute (HCRI), Hunan Children's Hospital, University of South China, Changsha, 410007, China.
| | - Yan Zhong
- Department of Child Healthcare, Hunan Children's Hospital, University of South China, Changsha, 410007, Hunan, China.
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18
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Albandar JM, Susin C, Hughes FJ. Manifestations of systemic diseases and conditions that affect the periodontal attachment apparatus: Case definitions and diagnostic considerations. J Clin Periodontol 2019; 45 Suppl 20:S171-S189. [PMID: 29926486 DOI: 10.1111/jcpe.12947] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 10/14/2017] [Accepted: 10/21/2017] [Indexed: 01/03/2023]
Abstract
OBJECTIVES This review proposes case definitions and diagnostic considerations of systemic disorders and conditions that affect the periodontal attachment apparatus. IMPORTANCE Periodontal diseases and certain systemic disorders share similar genetic and/or environmental etiological factors, and affected patients may show manifestations of both diseases. Characterizing these diseases and the nature of the association between them could have important diagnostic value and therapeutic implications for patients. FINDINGS Numerous systemic disorders and certain medications can affect the periodontal attachment apparatus and cause loss of periodontal attachment and alveolar bone. Although many of these disorders are rare or uncommon, they often cause significant loss of periodontal tissue by influencing periodontal inflammation or through mechanisms distinct from periodontitis. Most of these disorders are due to innate mechanisms and some are acquired via environmental factors or lifestyle. Several disorders affect periodontal inflammation through alterations in the host immune response to periodontal infection; others cause defects in the gingiva or periodontal connective tissue, instigate metabolic changes in the host that affect various tissues of the periodontal apparatus, or operate by other mechanisms. For some systemic disorders that are more common, their contribution to the loss of periodontal tissue is modest, while for others, contribution is not supported by clear evidence. Few systemic medications are associated with increased loss of periodontal tissue, and these are typically medications used in the treatment of malignancies. CONCLUSIONS This review identifies systemic diseases and conditions that can affect the periodontal attachment apparatus and cause loss of periodontal supporting tissues and, where possible, presents case definitions for these. Many of these diseases are associated with a profound loss of periodontal attachment and alveolar bone, and for some of these disorders the periodontal manifestations may be among the first signs of the disease. These case definitions may be useful in the early diagnosis of these diseases and may contribute to an improvement in the management of periodontal manifestations and improve the quality of life for these patients.
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Affiliation(s)
- Jasim M Albandar
- Department of Periodontology and Oral Implantology, Temple University School of Dentistry, Philadelphia, PA, USA
| | - Cristiano Susin
- Department of Periodontics, Augusta University Dental College of Georgia, Augusta, GA, USA
| | - Francis J Hughes
- Unit of Periodontology, Dental Institute, Kings College London, London, UK
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19
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Fogel BL. Collaborative science unites researchers and a novel spastic ataxia gene. Ann Neurol 2019; 83:1072-1074. [PMID: 29908061 DOI: 10.1002/ana.25262] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 04/30/2018] [Accepted: 05/17/2018] [Indexed: 12/16/2022]
Affiliation(s)
- Brent L Fogel
- Departments of Neurology and Human Genetics David Geffen School of Medicine, University of California, Los Angeles Los Angeles, CA
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20
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8q22.2q22.3 Microdeletion Syndrome Associated with Hearing Loss and Intractable Epilepsy. Case Rep Genet 2019; 2019:7608348. [PMID: 30733878 PMCID: PMC6348808 DOI: 10.1155/2019/7608348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/07/2018] [Accepted: 12/02/2018] [Indexed: 11/17/2022] Open
Abstract
8q22.2q22.3 microdeletion syndrome has been described in only seven patients. We present a new case from Colombia. The characteristics of this condition are developmental delay, microcephaly, seizures, and typical facial dysmorphism. We discuss the clinical phenotype of the patient presenting relevant findings like hearing loss and severe epilepsy and the possible relations between the phenotype and the genes involved in the microdeletion. We describe a female with developmental delay, microcephaly, epilepsy, severe short stature, impaired speech, facial dysmorphism, and congenital deafness. A minimal/maximal deletion of 5.238 Mb and 5.374Mb, respectively, at 8q22.2q22.3 was diagnosed using a genome-wide array. The clinical phenotype is similar to the others seven patients previously reported; however, the severity of epilepsy and the concomitant hearing loss is remarkable, characteristics previously observed independently in only two patients. The KCNS2 gene is located in the deleted regions (8q22.2). Therefore it is a possible candidate for explaining the complex neurologic phenotype.
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21
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CNV analysis using whole exome sequencing identified biallelic CNVs of VPS13B in siblings with intellectual disability. Eur J Med Genet 2018; 63:103610. [PMID: 30602132 DOI: 10.1016/j.ejmg.2018.12.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 11/21/2018] [Accepted: 12/29/2018] [Indexed: 01/04/2023]
Abstract
Cohen syndrome is an autosomal recessive disease characterized by myopia, retinal dystrophy, neutropenia, short stature, microcephaly, persistent hypotonia, intellectual disability (ID), and a distinct facial appearance. Cohen syndrome is caused by mutations, such as single nucleotide variants (SNVs) and small insertions/deletions, and copy number variations (CNVs) in vacuolar protein sorting 13 homolog B (VPS13B). Here, we report Japanese siblings with ID, who were subsequently diagnosed with Cohen syndrome by whole exome sequencing (WES). The older sister had hypotonia and mild to moderate ID. The younger sister had short stature, postnatal onset microcephaly, and developmental delay. No pathogenic mutations, including SNVs or small insertions/deletions, were found by WES. Comparative genomic hybridization (CGH)-array did not detect pathogenic copy-number variations. However, using log2-ratio values calculated from WES depth data, we detected pathogenic biallelic heterozygous CNVs in VPS13B in both sisters: a maternally-derived exons 8-15 deletion and a paternally-derived exons 32-33 deletion. Interestingly, the sisters did not show obvious clinical features suggestive of Cohen syndrome, including the distinct facial appearance. These results support the idea that the typical facial features of Cohen syndrome do not appear in early childhood, and that the late appearance of distinctive clinical features results in delayed diagnosis. Furthermore, these results show the possibility that CNV analysis using log2-ratio values calculated from WES depth data is a useful and effective method to detect CNVs, such as the deletion of multiple exons.
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22
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Valerio G, Maffeis C, Saggese G, Ambruzzi MA, Balsamo A, Bellone S, Bergamini M, Bernasconi S, Bona G, Calcaterra V, Canali T, Caroli M, Chiarelli F, Corciulo N, Crinò A, Di Bonito P, Di Pietrantonio V, Di Pietro M, Di Sessa A, Diamanti A, Doria M, Fintini D, Franceschi R, Franzese A, Giussani M, Grugni G, Iafusco D, Iughetti L, Lamborghini A, Licenziati MR, Limauro R, Maltoni G, Manco M, Reggiani LM, Marcovecchio L, Marsciani A, del Giudice EM, Morandi A, Morino G, Moro B, Nobili V, Perrone L, Picca M, Pietrobelli A, Privitera F, Purromuto S, Ragusa L, Ricotti R, Santamaria F, Sartori C, Stilli S, Street ME, Tanas R, Trifiró G, Umano GR, Vania A, Verduci E, Zito E. Diagnosis, treatment and prevention of pediatric obesity: consensus position statement of the Italian Society for Pediatric Endocrinology and Diabetology and the Italian Society of Pediatrics. Ital J Pediatr 2018; 44:88. [PMID: 30064525 PMCID: PMC6069785 DOI: 10.1186/s13052-018-0525-6] [Citation(s) in RCA: 128] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 06/07/2018] [Indexed: 01/06/2023] Open
Abstract
The Italian Consensus Position Statement on Diagnosis, Treatment and Prevention of Obesity in Children and Adolescents integrates and updates the previous guidelines to deliver an evidence based approach to the disease. The following areas were reviewed: (1) obesity definition and causes of secondary obesity; (2) physical and psychosocial comorbidities; (3) treatment and care settings; (4) prevention.The main novelties deriving from the Italian experience lie in the definition, screening of the cardiometabolic and hepatic risk factors and the endorsement of a staged approach to treatment. The evidence based efficacy of behavioral intervention versus pharmacological or surgical treatments is reported. Lastly, the prevention by promoting healthful diet, physical activity, sleep pattern, and environment is strongly recommended since the intrauterine phase.
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Affiliation(s)
- Giuliana Valerio
- Department of Movement Sciences and Wellbeing, University of Naples Parthenope, via Medina 40, 80133 Naples, Italy
| | - Claudio Maffeis
- Pediatric Diabetes and Metabolic Disorders Unit, University of Verona, Verona, Italy
| | - Giuseppe Saggese
- Department of Pediatrics, University Hospital of Pisa, Pisa, Italy
| | | | - Antonio Balsamo
- Department of Medical and Surgical Sciences, University Hospital S.Orsola-Malpighi, Bologna, Italy
| | - Simonetta Bellone
- Department of Health Sciences, University of Piemonte Orientale, Novara, Italy
| | | | - Sergio Bernasconi
- Italian Society for Pediatric Endocrinology and Diabetology (SIEDP), Parma, Italy
| | - Gianni Bona
- Department of Health Sciences, University of Piemonte Orientale, Novara, Italy
| | - Valeria Calcaterra
- Pediatrics Unit, University of Pavia and Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | | | - Margherita Caroli
- Italian Society for Obesity (SIO), Francavilla Fontana (Brindisi), Italy
| | | | - Nicola Corciulo
- Pediatric Unit, Hospital of Gallipoli, Gallipoli (Lecce), Italy
| | - Antonino Crinò
- Autoimmune Endocrine Diseases Unit, Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | - Procolo Di Bonito
- Department of Internal Medicine, “S. Maria delle Grazie”, Pozzuoli Hospital, Naples, Italy
| | | | - Mario Di Pietro
- Pediatric and Neonatal Unit, “G. Mazzini”Hospital, Teramo, Italy
| | - Anna Di Sessa
- Department of Woman, Child and General and Specialized Surgery, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Antonella Diamanti
- Artificial Nutrition Unit Bambino Gesù, Children’s Hospital, IRCCS, Rome, Italy
| | - Mattia Doria
- Italian Federation of Pediatricians (FIMP), Venice, Italy
| | - Danilo Fintini
- Endocrinology and Diabetology Unit Bambino Gesù Children Hospital, IRCCS, Rome, Italy
| | | | - Adriana Franzese
- Department of Translational Medical Science, Regional Center for Pediatric Diabetes, University Federico II of Naples, Naples, Italy
| | | | - Graziano Grugni
- Division of Auxology, Istituto Auxologico Italiano, IRCCS, Verbania, Italy
| | - Dario Iafusco
- Department of Woman, Child and General and Specialized Surgery, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Lorenzo Iughetti
- Pediatric Unit, University of Modena and Reggio Emilia, Modena, Italy
| | | | | | | | - Giulio Maltoni
- Department of Medical and Surgical Sciences, University Hospital S.Orsola-Malpighi, Bologna, Italy
| | - Melania Manco
- Research Area for Multifactorial Diseases, Children’s Hospital Bambino Gesù, Rome, Italy
| | | | | | | | - Emanuele Miraglia del Giudice
- Department of Woman, Child and General and Specialized Surgery, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Anita Morandi
- Pediatric Diabetes and Metabolic Disorders Unit, University Hospital of Verona, Verona, Italy
| | - Giuseppe Morino
- Nutrition Unit, Bambino Gesù Children’s Hospital IRCCS, Rome, Italy
| | | | - Valerio Nobili
- Department of Pediatrics and Infantile Neuropsychiatry, Sapienza University of Rome, Rome, Italy
- Hepatometabolic Unit, Bambino Gesù Children’s Hospital, IRCSS, Rome, Italy
| | - Laura Perrone
- Department of Woman, Child and General and Specialized Surgery, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | | | | | | | | | | | - Roberta Ricotti
- Department of Health Sciences, University of Piemonte Orientale, Novara, Italy
| | - Francesca Santamaria
- Department of Translational Medical Science, Regional Center for Pediatric Diabetes, University Federico II of Naples, Naples, Italy
| | - Chiara Sartori
- Department of Obstetrics, Gynaecology and Paediatrics, Arcispedale S.Maria Nuova-IRCCS, Reggio Emilia, Italy
| | | | - Maria Elisabeth Street
- Department of Obstetrics, Gynaecology and Paediatrics, Arcispedale S.Maria Nuova-IRCCS, Reggio Emilia, Italy
| | - Rita Tanas
- Italian Society for Pediatric Endocrinology and Diabetology (SIEDP), Ferrara, Italy
| | | | - Giuseppina Rosaria Umano
- Department of Woman, Child and General and Specialized Surgery, University of Campania “Luigi Vanvitelli”, Naples, Italy
| | - Andrea Vania
- Department of Pediatrics and Infantile Neuropsychiatry, Sapienza University of Rome, Rome, Italy
| | - Elvira Verduci
- Deparment of Pediatrics, San Paolo Hospital, University of Milan, Milan, Italy
| | - Eugenio Zito
- Department of Social Sciences, University of Naples Federico II, Naples, Italy
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23
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Albandar JM, Susin C, Hughes FJ. Manifestations of systemic diseases and conditions that affect the periodontal attachment apparatus: Case definitions and diagnostic considerations. J Periodontol 2018; 89 Suppl 1:S183-S203. [DOI: 10.1002/jper.16-0480] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 10/14/2017] [Accepted: 10/21/2017] [Indexed: 12/17/2022]
Affiliation(s)
- Jasim M. Albandar
- Department of Periodontology and Oral Implantology; Temple University School of Dentistry; Philadelphia PA USA
| | - Cristiano Susin
- Department of Periodontics; Augusta University Dental College of Georgia; Augusta GA USA
| | - Francis J. Hughes
- Unit of Periodontology; Dental Institute; Kings College London; London UK
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24
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Yang C, Hou M, Li Y, Sun D, Guo Y, Liu P, Liu Y, Song J, Zhang N, Wei W, Chen Z. Gene analysis: A rare gene disease of intellectual deficiency-Cohen syndrome. Int J Dev Neurosci 2018; 68:83-88. [PMID: 29758347 DOI: 10.1016/j.ijdevneu.2018.05.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 04/28/2018] [Accepted: 05/08/2018] [Indexed: 10/16/2022] Open
Abstract
Cohen syndrome is a rare, genetic, connective-tissue disorder, which is caused by mutations in the gene COH1 (VPS13B, Vacuolar Protein Sorting 13 Homolog B) at the chromosome 8q22. The disease is rare reported, which major clinical features include postnatal microcephaly, obesity, short stature, intellectual disability, progressive retinal dystrophy, intermittent neutropenia and many other unusual facial feature. We report four patients in China who were diagnosed with Cohen syndrome by genetic testing and clinical manifestations. At the same time, we review the related literature, and further expound the molecular mechanism of the disease, a variety of clinical manifestations, treatment and prognosis.
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Affiliation(s)
- Chengqing Yang
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong 266000, PR China.
| | - Mei Hou
- Pediatric Department of the Qingdao Women & Children Hospital, No. 6 Tongfu Road, Shandong 266000, PR China.
| | - Yutang Li
- Pediatric Department of the Qingdao Women & Children Hospital, No. 6 Tongfu Road, Shandong 266000, PR China.
| | - Dianrong Sun
- Pediatric Department of the Qingdao Women & Children Hospital, No. 6 Tongfu Road, Shandong 266000, PR China.
| | - Ya Guo
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong 266000, PR China.
| | - Peipei Liu
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong 266000, PR China.
| | - Yedan Liu
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong 266000, PR China.
| | - Jie Song
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong 266000, PR China.
| | - Na Zhang
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong 266000, PR China.
| | - Wei Wei
- Kangso Medical Inspection Co.,Ltd, No.65 Haidian District, Xingshikou Road Yiyuan Cultural Creative Industry Base C District No. 10, Floor 2, 201-203, Beijing 100195, PR China.
| | - Zongbo Chen
- Pediatric Department of the Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Shandong 266000, PR China.
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25
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Uyhazi KE, Binenbaum G, Carducci N, Zackai EH, Aleman TS. Early photoreceptor outer segment loss and retinoschisis in Cohen syndrome. Ophthalmic Genet 2018; 39:399-404. [DOI: 10.1080/13816810.2018.1459735] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Katherine E. Uyhazi
- Scheie Eye Institute at the Perelman Center for Advanced Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Gil Binenbaum
- Scheie Eye Institute at the Perelman Center for Advanced Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Ophthalmology, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Nicholas Carducci
- Scheie Eye Institute at the Perelman Center for Advanced Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Elaine H. Zackai
- Division of Human Genetics, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Tomas S. Aleman
- Scheie Eye Institute at the Perelman Center for Advanced Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Ophthalmology, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
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26
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Stryjecki C, Alyass A, Meyre D. Ethnic and population differences in the genetic predisposition to human obesity. Obes Rev 2018; 19:62-80. [PMID: 29024387 DOI: 10.1111/obr.12604] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 06/17/2017] [Accepted: 08/02/2017] [Indexed: 12/22/2022]
Abstract
Obesity rates have escalated to the point of a global pandemic with varying prevalence across ethnic groups. These differences are partially explained by lifestyle factors in addition to genetic predisposition to obesity. This review provides a comprehensive examination of the ethnic differences in the genetic architecture of obesity. Using examples from evolution, heritability, admixture, monogenic and polygenic studies of obesity, we provide explanations for ethnic differences in the prevalence of obesity. The debate over definitions of race and ethnicity, the advantages and limitations of multi-ethnic studies and future directions of research are also discussed. Multi-ethnic studies have great potential to provide a better understanding of ethnic differences in the prevalence of obesity that may result in more targeted and personalized obesity treatments.
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Affiliation(s)
- C Stryjecki
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada
| | - A Alyass
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada
| | - D Meyre
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
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27
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Rzepnikowska W, Flis K, Muñoz-Braceras S, Menezes R, Escalante R, Zoladek T. Yeast and other lower eukaryotic organisms for studies of Vps13 proteins in health and disease. Traffic 2017; 18:711-719. [PMID: 28846184 DOI: 10.1111/tra.12523] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 08/23/2017] [Accepted: 08/23/2017] [Indexed: 12/25/2022]
Abstract
Human Vps13 proteins are associated with several diseases, including the neurodegenerative disorder Chorea-acanthocytosis (ChAc), yet the biology of these proteins is still poorly understood. Studies in Saccharomyces cerevisiae, Dictyostelium discoideum, Tetrahymena thermophila and Drosophila melanogaster point to the involvement of Vps13 in cytoskeleton organization, vesicular trafficking, autophagy, phagocytosis, endocytosis, proteostasis, sporulation and mitochondrial functioning. Recent findings show that yeast Vps13 binds to phosphatidylinositol lipids via 4 different regions and functions at membrane contact sites, enlarging the list of Vps13 functions. This review describes the great potential of simple eukaryotes to decipher disease mechanisms in higher organisms and highlights novel insights into the pathological role of Vps13 towards ChAc.
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Affiliation(s)
- Weronika Rzepnikowska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Krzysztof Flis
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | | | - Regina Menezes
- iBET, Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal.,Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Ricardo Escalante
- Instituto de Investigaciones Biomédicas "Alberto Sols" (CSIC-UAM), Madrid, Spain
| | - Teresa Zoladek
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
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28
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Exome sequencing identifies pathogenic variants of VPS13B in a patient with familial 16p11.2 duplication. BMC MEDICAL GENETICS 2016; 17:78. [PMID: 27832746 PMCID: PMC5105257 DOI: 10.1186/s12881-016-0340-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 10/20/2016] [Indexed: 12/05/2022]
Abstract
Background The recurrent microduplication of 16p11.2 (dup16p11.2) is associated with a broad spectrum of neurodevelopmental disorders (NDD) confounded by incomplete penetrance and variable expressivity. This inter- and intra-familial clinical variability highlights the importance of personalized genetic counselling in individuals at-risk. Case presentation In this study, we performed whole exome sequencing (WES) to look for other genomic alterations that could explain the clinical variability in a family with a boy presenting with NDD who inherited the dup16p11.2 from his apparently healthy mother. We identified novel splicing variants of VPS13B (8q22.2) in the proband with compound heterozygous inheritance. Two VPS13B mutations abolished the canonical splice sites resulting in low RNA expression in transformed lymphoblasts of the proband. VPS13B mutation causes Cohen syndrome (CS) consistent with the proband’s phenotype (intellectual disability (ID), microcephaly, facial gestalt, retinal dystrophy, joint hypermobility and neutropenia). The new diagnosis of CS has important health implication for the proband, provides the opportunity for more meaningful and accurate genetic counselling for the family; and underscores the importance of longitudinally following patients for evolving phenotypic features. Conclusions This is the first report of a co-occurrence of pathogenic variants with familial dup16p11.2. Our finding suggests that the variable expressivity among carriers of rare putatively pathogenic CNVs such as dup16p11.2 warrants further study by WES and individualized genetic counselling of families with such CNVs. Electronic supplementary material The online version of this article (doi:10.1186/s12881-016-0340-0) contains supplementary material, which is available to authorized users.
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29
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Zhou L, Li T, Xing YQ, Li Y, Wu QS, Zhang MJ. Novel TRPM1 mutations in two Chinese families with early-onset high myopia, with or without complete congenital stationary night blindness. Int J Ophthalmol 2016; 9:1396-1402. [PMID: 27803854 DOI: 10.18240/ijo.2016.10.05] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Accepted: 05/25/2015] [Indexed: 12/29/2022] Open
Abstract
AIM To investigate the relationship between high myopia [with or without complete congenital stationary night blindness (CSNB1)] and TRPM1 and NYX. METHODS Two unrelated families with early-onset high myopia (eoHM) and 96 normal controls were recruited. Sanger sequencing or clone sequencing were used for mutation screening. Further analyses of the available family members and the 96 normal controls were subsequently conducted to obtain additional evidence of the pathogenicity of these variants. The initial diagnosis of the probands was eoHM. We performed a further comprehensive examination of the available family members after mutations were detected in TRPM1 or NYX. RESULTS Two novel compound heterozygous mutations in TRPM1 were detected in the recruited families. The proband in family A with eoHM carried a c.2594C>T missense mutation in exon 19 and a c.669+3_669+6delAAGT splicing mutation, which was co-segregated with CSNB1 in this family. A patient in family B with a compound heterozygous missense mutation (c.3262G>A and c.3250T>C) was detected. No mutations were found in NYX. These two identified compound heterozygous mutations were not found in the 96 normal controls. After further examination of the family members, the patients in family A could be diagnosed as eoHM with CSNB1. However due to the limited clinic data, the patient in family B cloud not clearly diagnosed as CSNB1. CONCLUSION This study has expanded the mutation spectrum of TRPM1 for CSNB1 and additional studies are needed to elucidate the association between isolated high myopia and TRPM1 and NYX.
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Affiliation(s)
- Lin Zhou
- Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China
| | - Tuo Li
- Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China
| | - Yi-Qiao Xing
- Department of Ophthalmology, Remin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
| | - Yin Li
- Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China
| | - Qing-Song Wu
- Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China
| | - Mao-Ju Zhang
- Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China
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30
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Rafiq MA, Leblond CS, Saqib MAN, Vincent AK, Ambalavanan A, Khan FS, Ayaz M, Shaheen N, Spiegelman D, Ali G, Amin-ud-Din M, Laurent S, Mahmood H, Christian M, Ali N, Fennell A, Nanjiani Z, Egger G, Caron C, Waqas A, Ayub M, Rasheed S, Forgeot d'Arc B, Johnson A, So J, Brohi MQ, Mottron L, Ansar M, Vincent JB, Xiong L. Novel VPS13B Mutations in Three Large Pakistani Cohen Syndrome Families Suggests a Baloch Variant with Autistic-Like Features. BMC MEDICAL GENETICS 2015; 16:41. [PMID: 26104215 PMCID: PMC4631108 DOI: 10.1186/s12881-015-0183-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 05/29/2015] [Indexed: 12/27/2022]
Abstract
Background Cohen Syndrome (COH1) is a rare autosomal recessive disorder, principally identified by ocular, neural and muscular deficits. We identified three large consanguineous Pakistani families with intellectual disability and in some cases with autistic traits. Methods Clinical assessments were performed in order to allow comparison of clinical features with other VPS13B mutations. Homozygosity mapping followed by whole exome sequencing and Sanger sequencing strategies were used to identify disease-related mutations. Results We identified two novel homozygous deletion mutations in VPS13B, firstly a 1 bp deletion, NM_017890.4:c.6879delT; p.Phe2293Leufs*24, and secondly a deletion of exons 37-40, which co-segregate with affected status. In addition to COH1-related traits, autistic features were reported in a number of family members, contrasting with the “friendly” demeanour often associated with COH1. The c.6879delT mutation is present in two families from different regions of the country, but both from the Baloch sub-ethnic group, and with a shared haplotype, indicating a founder effect among the Baloch population. Conclusion We suspect that the c.6879delT mutation may be a common cause of COH1 and similar phenotypes among the Baloch population. Additionally, most of the individuals with the c.6879delT mutation in these two families also present with autistic like traits, and suggests that this variant may lead to a distinct autistic-like COH1 subgroup. Electronic supplementary material The online version of this article (doi:10.1186/s12881-015-0183-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Muhammad Arshad Rafiq
- Molecular Neuropsychiatry & Development Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada. .,Currently at: Department of Physiology and Experimental Medicine (PEM), Hospital for Sick Children, Toronto, ON, Canada.
| | - Claire S Leblond
- CHUM Research Center - Notre Dame Hospital, Montreal, Canada. .,Currently at: Montreal Neurological Institute, McGill University, Montreal, QC, Canada.
| | - Muhammad Arif Nadeem Saqib
- Department of Biochemistry, Quaid-I-Azam University, and Pakistan Medical Research Council, Islamabad, Pakistan.
| | - Akshita K Vincent
- Molecular Neuropsychiatry & Development Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada.
| | - Amirthagowri Ambalavanan
- CHUM Research Center - Notre Dame Hospital, Montreal, Canada. .,Currently at: Montreal Neurological Institute, McGill University, Montreal, QC, Canada.
| | - Falak Sher Khan
- Department of Biochemistry, Quaid-I-Azam University, and Pakistan Medical Research Council, Islamabad, Pakistan.
| | - Muhammad Ayaz
- The Lahore Institute for Research and Development, Lahore, Punjab, Pakistan.
| | - Naseema Shaheen
- University of Education, Township Campus, College Road, Lahore, Punjab, Pakistan.
| | - Dan Spiegelman
- CHUM Research Center - Notre Dame Hospital, Montreal, Canada. .,Currently at: Montreal Neurological Institute, McGill University, Montreal, QC, Canada.
| | - Ghazanfar Ali
- Department of Biotechnology, University of Azad Jammu and Kashmir, P.O. Box 13100, Muzaffarabad, Pakistan.
| | - Muhammad Amin-ud-Din
- Dept: zoology, University of Education, Lahore, Campus Dera Ghazi Khan, Punjab, Pakistan.
| | - Sandra Laurent
- CHUM Research Center - Notre Dame Hospital, Montreal, Canada. .,Currently at: Montreal Neurological Institute, McGill University, Montreal, QC, Canada.
| | - Huda Mahmood
- Molecular Neuropsychiatry & Development Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada.
| | | | - Nadir Ali
- Department of Biochemistry, Quaid-I-Azam University, and Pakistan Medical Research Council, Islamabad, Pakistan.
| | - Alanna Fennell
- Molecular Neuropsychiatry & Development Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada.
| | | | - Gerald Egger
- Molecular Neuropsychiatry & Development Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada. .,Institute of Human Genetics, Medical University of Graz, Graz, A-8010, Austria.
| | - Chantal Caron
- Hôpital Rivière-des-Prairies, Montreal, Canada. .,Département de Psychiatrie, Université de Montréal, Montreal, Canada.
| | - Ahmed Waqas
- Department of Biochemistry, Quaid-I-Azam University, and Pakistan Medical Research Council, Islamabad, Pakistan.
| | - Muhammad Ayub
- The Lahore Institute for Research and Development, Lahore, Punjab, Pakistan. .,Division of Developmental Disabilities, Department of Psychiatry, Queen's University, Kingston, ON, Canada.
| | | | - Baudouin Forgeot d'Arc
- Hôpital Rivière-des-Prairies, Montreal, Canada. .,Département de Psychiatrie, Université de Montréal, Montreal, Canada. .,Research Centre, Montreal Mental Health University Institute, 7331, rue Hochelaga, Montréal, QC, H1N 3 V2, Canada.
| | - Amelie Johnson
- Département de Psychiatrie, Université de Montréal, Montreal, Canada. .,Research Centre, Montreal Mental Health University Institute, 7331, rue Hochelaga, Montréal, QC, H1N 3 V2, Canada.
| | - Joyce So
- The Fred A. Litwin Family Centre in Genetic Medicine, University Health Network and Mount Sinai Hospital, Toronto, Canada. .,The Centre for Addiction and Mental Health, Toronto, Canada. .,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada.
| | | | - Laurent Mottron
- Hôpital Rivière-des-Prairies, Montreal, Canada. .,Département de Psychiatrie, Université de Montréal, Montreal, Canada. .,Research Centre, Montreal Mental Health University Institute, 7331, rue Hochelaga, Montréal, QC, H1N 3 V2, Canada.
| | - Muhammad Ansar
- Department of Biochemistry, Quaid-I-Azam University, and Pakistan Medical Research Council, Islamabad, Pakistan.
| | - John B Vincent
- Molecular Neuropsychiatry & Development Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, M5T 1R8, Canada. .,Department of Psychiatry, University of Toronto, Toronto, ON, Canada.
| | - Lan Xiong
- CHUM Research Center - Notre Dame Hospital, Montreal, Canada. .,Département de Psychiatrie, Université de Montréal, Montreal, Canada. .,Research Centre, Montreal Mental Health University Institute, 7331, rue Hochelaga, Montréal, QC, H1N 3 V2, Canada.
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Schlögel MJ, Mendola A, Fastré E, Vasudevan P, Devriendt K, de Ravel TJL, Van Esch H, Casteels I, Arroyo Carrera I, Cristofoli F, Fieggen K, Jones K, Lipson M, Balikova I, Singer A, Soller M, Mercedes Villanueva M, Revencu N, Boon LM, Brouillard P, Vikkula M. No evidence of locus heterogeneity in familial microcephaly with or without chorioretinopathy, lymphedema, or mental retardation syndrome. Orphanet J Rare Dis 2015; 10:52. [PMID: 25934493 PMCID: PMC4464120 DOI: 10.1186/s13023-015-0271-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 04/20/2015] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Microcephaly with or without chorioretinopathy, lymphedema, or mental retardation syndrome (MCLMR) is a rare autosomal dominant disorder with variable expressivity. It is characterized by mild-to-severe microcephaly, often associated with intellectual disability, ocular defects and lymphedema. It can be sporadic or inherited. Eighty-seven patients have been described to carry a mutation in KIF11, which encodes a homotetrameric motor kinesin, EG5. METHODS We tested 23 unreported MCLMR index patients for KIF11. We also reviewed the clinical phenotypes of all our patients as well as of those described in previously published studies. RESULTS We identified 14 mutations, 12 of which are novel. We detected mutations in 12 affected individuals, from 6 out of 6 familial cases, and in 8 out of 17 sporadic patients. Phenotypic evaluation of patients (our 26 + 61 earlier published = 87) revealed microcephaly in 91%, eye anomalies in 72%, intellectual disability in 67% and lymphedema in 47% of the patients. Unaffected carriers were rare (4 out of 87: 5%). Family history is not a requisite for diagnosis; 31% (16 out of 52) were de novo cases. CONCLUSIONS All inherited cases, and 50% of sporadic cases of MCLMR are due to germline KIF11 mutations. It is possible that mosaic KIF11 mutations cause the remainder of sporadic cases, which the methods employed here were not designed to detect. On the other hand, some of them might have another mimicking disorder and genetic defect, as microcephaly is highly heterogeneous. In aggregate, KIF11 mutations likely cause the majority, if not all, of MCLMR.
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Affiliation(s)
- Matthieu J Schlögel
- Laboratory of Human Molecular Genetics, de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 74, bte B1.74.06, B-1200, Brussels, Belgium.
| | - Antonella Mendola
- Laboratory of Human Molecular Genetics, de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 74, bte B1.74.06, B-1200, Brussels, Belgium.
| | - Elodie Fastré
- Laboratory of Human Molecular Genetics, de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 74, bte B1.74.06, B-1200, Brussels, Belgium.
| | - Pradeep Vasudevan
- Department of Clinical Genetics, University Hospitals of Leicester, Leicester Royal Infirmary, Leicester, LE1 5WW, UK.
| | - Koen Devriendt
- Center for Human Genetics, University Hospitals Leuven, KU Leuven, 3000, Leuven, Belgium.
| | - Thomy J L de Ravel
- Center for Human Genetics, University Hospitals Leuven, KU Leuven, 3000, Leuven, Belgium.
| | - Hilde Van Esch
- Center for Human Genetics, University Hospitals Leuven, KU Leuven, 3000, Leuven, Belgium.
| | - Ingele Casteels
- Department of Ophthalmology, St Rafael University Hospitals, 3000, Leuven, Belgium.
| | | | - Francesca Cristofoli
- Center for Human Genetics, University Hospitals Leuven, KU Leuven, 3000, Leuven, Belgium.
| | - Karen Fieggen
- Division of Human Genetics, University of Cape Town, 7700, Cape Town, South Africa.
| | - Katheryn Jones
- Medical Genetics, Kaiser Permanente, Sacramento, CA, 95815, USA.
| | - Mark Lipson
- Medical Genetics, Kaiser Permanente, Sacramento, CA, 95815, USA.
| | - Irina Balikova
- Department of Ophthalmology, Queen Fabiola Children's University Hospital (HUDERF), 1020, Brussels, Belgium.
| | - Ami Singer
- Pediatrics and Medical Genetics, Barzilai Medical Center, 78306, Ashkelon, Israel.
| | - Maria Soller
- Department of Clinical Genetics, Lund University Hospital, 221 85, Lund, Sweden.
| | - María Mercedes Villanueva
- General Hospital of Florencio Varela, Children's Hospital Dr. Pedro Elizalde and Foundation for Neurological Diseases of Childhood (FLENI), C1270AAN, Buenos Aires, Capital Federal, Argentina.
| | - Nicole Revencu
- Laboratory of Human Molecular Genetics, de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 74, bte B1.74.06, B-1200, Brussels, Belgium. .,Center for Human Genetics, Cliniques universitaires Saint-Luc, Université catholique de Louvain, 1200, Brussels, Belgium.
| | - Laurence M Boon
- Laboratory of Human Molecular Genetics, de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 74, bte B1.74.06, B-1200, Brussels, Belgium. .,Center for Vascular Anomalies, Cliniques universitaires Saint-Luc, Université catholique de Louvain, 1200, Brussels, Belgium.
| | - Pascal Brouillard
- Laboratory of Human Molecular Genetics, de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 74, bte B1.74.06, B-1200, Brussels, Belgium.
| | - Miikka Vikkula
- Laboratory of Human Molecular Genetics, de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 74, bte B1.74.06, B-1200, Brussels, Belgium. .,Center for Vascular Anomalies, Cliniques universitaires Saint-Luc, Université catholique de Louvain, 1200, Brussels, Belgium. .,Walloon Excellence in Lifesciences and Biotechnology (WELBIO), Université catholique de Louvain, 1200, Brussels, Belgium.
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Ionita-Laza I, Capanu M, De Rubeis S, McCallum K, Buxbaum JD. Identification of rare causal variants in sequence-based studies: methods and applications to VPS13B, a gene involved in Cohen syndrome and autism. PLoS Genet 2014; 10:e1004729. [PMID: 25502226 PMCID: PMC4263785 DOI: 10.1371/journal.pgen.1004729] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 09/02/2014] [Indexed: 11/18/2022] Open
Abstract
Pinpointing the small number of causal variants among the abundant naturally occurring genetic variation is a difficult challenge, but a crucial one for understanding precise molecular mechanisms of disease and follow-up functional studies. We propose and investigate two complementary statistical approaches for identification of rare causal variants in sequencing studies: a backward elimination procedure based on groupwise association tests, and a hierarchical approach that can integrate sequencing data with diverse functional and evolutionary conservation annotations for individual variants. Using simulations, we show that incorporation of multiple bioinformatic predictors of deleteriousness, such as PolyPhen-2, SIFT and GERP++ scores, can improve the power to discover truly causal variants. As proof of principle, we apply the proposed methods to VPS13B, a gene mutated in the rare neurodevelopmental disorder called Cohen syndrome, and recently reported with recessive variants in autism. We identify a small set of promising candidates for causal variants, including two loss-of-function variants and a rare, homozygous probably-damaging variant that could contribute to autism risk.
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Affiliation(s)
- Iuliana Ionita-Laza
- Department of Biostatistics, Columbia University, New York, New York, United States of America
- * E-mail:
| | - Marinela Capanu
- Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
| | - Silvia De Rubeis
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Departments of Psychiatry, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Kenneth McCallum
- Department of Biostatistics, Columbia University, New York, New York, United States of America
| | - Joseph D. Buxbaum
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Departments of Psychiatry, Mount Sinai School of Medicine, New York, New York, United States of America
- Departments of Genetics and Genomic Sciences, and Neuroscience, and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Mindich Child Health and Development Institute, Mount Sinai School of Medicine, New York, New York, United States of America
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Prokudin I, Li D, He S, Guo Y, Goodwin L, Wilson M, Rose L, Tian L, Chen Y, Liang J, Keating B, Xu X, Jamieson RV, Hakonarson H. Value of whole exome sequencing for syndromic retinal dystrophy diagnosis in young patients. Clin Exp Ophthalmol 2014; 43:132-8. [DOI: 10.1111/ceo.12391] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 06/25/2014] [Indexed: 12/30/2022]
Affiliation(s)
- Ivan Prokudin
- Eye and Developmental Genetics Research Group; The Children's Hospital at Westmead; Sydney New South Wales Australia
- Eye Genetics Group; Children's Medical Research Institute; Sydney New South Wales Australia
| | - Dong Li
- Center for Applied Genomics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania USA
| | - Sijie He
- BGI-Shenzhen; Shenzhen China
- BGI Education Center; University of Chinese Academy of Sciences; Shenzhen China
| | - Yiran Guo
- Center for Applied Genomics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania USA
| | - Linda Goodwin
- Department of Clinical Genetics; Nepean Hospital; Sydney New South Wales Australia
| | - Meredith Wilson
- Department of Clinical Genetics; The Children's Hospital at Westmead; Sydney New South Wales Australia
| | - Loreto Rose
- Ophthalmology Department; Macquarie University Hospital; Macquarie University; Sydney New South Wales Australia
| | - Lifeng Tian
- Center for Applied Genomics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania USA
| | | | | | - Brendan Keating
- Division of Human Genetics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania USA
- Department of Pediatrics; The Perelman School of Medicine; University of Pennsylvania; Philadelphia Pennsylvania USA
| | - Xun Xu
- BGI-Shenzhen; Shenzhen China
| | - Robyn V Jamieson
- Eye and Developmental Genetics Research Group; The Children's Hospital at Westmead; Sydney New South Wales Australia
- Eye Genetics Group; Children's Medical Research Institute; Sydney New South Wales Australia
- Discipline of Ophthalmology and Save Sight Institute; University of Sydney; Sydney New South Wales Australia
- Disciplines of Paediatrics and Child Health and Genetic Medicine; University of Sydney; Sydney New South Wales Australia
| | - Hakon Hakonarson
- Division of Human Genetics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania USA
- Department of Pediatrics; The Perelman School of Medicine; University of Pennsylvania; Philadelphia Pennsylvania USA
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Abstract
Advances in genetic tools and sequencing technology in the past few years have vastly expanded our understanding of the genetics of neurodevelopmental disorders. Recent high-throughput sequencing analyses of structural brain malformations, cognitive and neuropsychiatric disorders, and localized cortical dysplasias have uncovered a diverse genetic landscape beyond classic Mendelian patterns of inheritance. The underlying genetic causes of neurodevelopmental disorders implicate numerous cell biological pathways critical for normal brain development.
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Affiliation(s)
- Wen F Hu
- Division of Genetics and Genomics, Department of Medicine; Manton Center for Orphan Disease Research; and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115; , ,
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35
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Ocular Involvement in Primary Immunodeficiency Diseases. J Clin Immunol 2013; 34:23-38. [DOI: 10.1007/s10875-013-9974-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 11/20/2013] [Indexed: 12/18/2022]
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36
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Mason SL, Jepson R, Maltman M, Batchelor DJ. Presentation and management of trapped neutrophil syndrome (TNS) in UK Border collies. J Small Anim Pract 2013; 55:57-60. [PMID: 24032537 DOI: 10.1111/jsap.12134] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Three UK bred Border collie puppies were presented for investigation of pyrexia and severe lameness with associated joint swelling. Investigations revealed neutropenia, radiographic findings suggesting metaphyseal osteopathy, and polyarthritis and all dogs were subsequently confirmed with trapped neutrophil syndrome. Clinical improvement was seen after treatment with prednisolone and antibiotics and the dogs all survived to adulthood with a good short- to medium-term outcome. Trapped neutrophil syndrome is an important differential diagnosis for young Border collie dogs in the UK presenting with pyrexia, neutropenia and musculoskeletal signs.
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Affiliation(s)
- S L Mason
- School of Veterinary Science, University of Liverpool, Neston, CH64 7TE
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37
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Zafeiriou DI, Ververi A, Dafoulis V, Kalyva E, Vargiami E. Autism spectrum disorders: the quest for genetic syndromes. Am J Med Genet B Neuropsychiatr Genet 2013; 162B:327-66. [PMID: 23650212 DOI: 10.1002/ajmg.b.32152] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Accepted: 03/01/2013] [Indexed: 11/10/2022]
Abstract
Autism spectrum disorders (ASD) are a heterogeneous group of neurodevelopmental disabilities with various etiologies, but with a heritability estimate of more than 90%. Although the strong correlation between autism and genetic factors has been long established, the exact genetic background of ASD remains unclear. A number of genetic syndromes manifest ASD at higher than expected frequencies compared to the general population. These syndromes account for more than 10% of all ASD cases and include tuberous sclerosis, fragile X, Down, neurofibromatosis, Angelman, Prader-Willi, Williams, Duchenne, etc. Clinicians are increasingly required to recognize genetic disorders in individuals with ASD, in terms of providing proper care and prognosis to the patient, as well as genetic counseling to the family. Vice versa, it is equally essential to identify ASD in patients with genetic syndromes, in order to ensure correct management and appropriate educational placement. During investigation of genetic syndromes, a number of issues emerge: impact of intellectual disability in ASD diagnoses, identification of autistic subphenotypes and differences from idiopathic autism, validity of assessment tools designed for idiopathic autism, possible mechanisms for the association with ASD, etc. Findings from the study of genetic syndromes are incorporated into the ongoing research on autism etiology and pathogenesis; different syndromes converge upon common biological backgrounds (such as disrupted molecular pathways and brain circuitries), which probably account for their comorbidity with autism. This review paper critically examines the prevalence and characteristics of the main genetic syndromes, as well as the possible mechanisms for their association with ASD.
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38
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Yu T, Chahrour M, Coulter M, Jiralerspong S, Okamura-Ikeda K, Ataman B, Schmitz-Abe K, Harmin D, Adli M, Malik A, D’Gama A, Lim E, Sanders S, Mochida G, Partlow J, Sunu C, Felie J, Rodriguez J, Nasir R, Ware J, Joseph R, Hill R, Kwan B, Al-Saffar M, Mukaddes N, Hashmi A, Balkhy S, Gascon G, Hisama F, LeClair E, Poduri A, Oner O, Al-Saad S, Al-Awadi S, Bastaki L, Ben-Omran T, Teebi A, Al-Gazali L, Eapen V, Stevens C, Rappaport L, Gabriel S, Markianos K, State M, Greenberg M, Taniguchi H, Braverman N, Morrow E, Walsh C. Using whole-exome sequencing to identify inherited causes of autism. Neuron 2013; 77:259-73. [PMID: 23352163 PMCID: PMC3694430 DOI: 10.1016/j.neuron.2012.11.002] [Citation(s) in RCA: 320] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2012] [Indexed: 01/01/2023]
Abstract
Despite significant heritability of autism spectrum disorders (ASDs), their extreme genetic heterogeneity has proven challenging for gene discovery. Studies of primarily simplex families have implicated de novo copy number changes and point mutations, but are not optimally designed to identify inherited risk alleles. We apply whole-exome sequencing (WES) to ASD families enriched for inherited causes due to consanguinity and find familial ASD associated with biallelic mutations in disease genes (AMT, PEX7, SYNE1, VPS13B, PAH, and POMGNT1). At least some of these genes show biallelic mutations in nonconsanguineous families as well. These mutations are often only partially disabling or present atypically, with patients lacking diagnostic features of the Mendelian disorders with which these genes are classically associated. Our study shows the utility of WES for identifying specific genetic conditions not clinically suspected and the importance of partial loss of gene function in ASDs.
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Affiliation(s)
- T.W. Yu
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- The Autism Consortium, Boston, Massachusetts, USA, 02115
- Harvard Medical School, Boston, Massachusetts, USA, 02115
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA, 02114
| | - M.H. Chahrour
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- The Autism Consortium, Boston, Massachusetts, USA, 02115
- Harvard Medical School, Boston, Massachusetts, USA, 02115
| | - M.E. Coulter
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Harvard Medical School, Boston, Massachusetts, USA, 02115
| | - S. Jiralerspong
- Department of Human Genetics and Pediatrics, McGill University, Montreal Children’s Hospital Research Institute, Montreal, Quebec, Canada, H3H1P3
| | - K. Okamura-Ikeda
- Institute for Enzyme Research, The University of Tokushima, Tokushima, Japan
| | - B. Ataman
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, USA, 02115
| | - K. Schmitz-Abe
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Harvard Medical School, Boston, Massachusetts, USA, 02115
| | - D.A. Harmin
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, USA, 02115
| | - M. Adli
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Virginia, Charlottesville, Virginia, USA, 22908
| | - A.N. Malik
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, USA, 02115
| | - A.M. D’Gama
- Harvard Medical School, Boston, Massachusetts, USA, 02115
| | - E.T. Lim
- Analytic and Translational Genetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, USA, 02114
| | - S.J. Sanders
- Department of Genetics, Center for Human Genetics and Genomics and Program on Neurogenetics, Yale University School of Medicine, New Haven, Connecticut, USA, 06510
| | - G.H. Mochida
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Harvard Medical School, Boston, Massachusetts, USA, 02115
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA, 02114
| | - J.N. Partlow
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
| | - C.M. Sunu
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
| | - J.M. Felie
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
| | - J. Rodriguez
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
| | - R.H. Nasir
- Harvard Medical School, Boston, Massachusetts, USA, 02115
- Division of Developmental Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
| | - J. Ware
- Harvard Medical School, Boston, Massachusetts, USA, 02115
- Division of Developmental Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
| | - R.M. Joseph
- The Autism Consortium, Boston, Massachusetts, USA, 02115
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA, 02118
| | - R.S. Hill
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Harvard Medical School, Boston, Massachusetts, USA, 02115
| | - B.Y. Kwan
- Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada, N6A 5C1
| | - M. Al-Saffar
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Department of Paediatrics, Faculty of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - N.M. Mukaddes
- Istanbul Faculty of Medicine, Department of Child Psychiatry, Istanbul University, Istanbul, Turkey
| | - A. Hashmi
- Armed Forces Hospital, King Abdulaziz Naval Base, Jubail, Kingdom of Saudi Arabia
| | - S. Balkhy
- Department of Neurosciences and Pediatrics, King Faisal Specialist Hospital and Research Center, Jeddah, Kingdom of Saudi Arabia
| | - G.G. Gascon
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA, 02114
- Istanbul Faculty of Medicine, Department of Child Psychiatry, Istanbul University, Istanbul, Turkey
- Clinical Neurosciences and Pediatrics, Brown University School of Medicine, Providence, Rhode Island, 02912
| | - F.M. Hisama
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, Washington, USA, 98195
| | - E. LeClair
- Harvard Medical School, Boston, Massachusetts, USA, 02115
- Division of Developmental Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
| | - A. Poduri
- Harvard Medical School, Boston, Massachusetts, USA, 02115
- Department of Neurology, Boston Children’s Hospital, Boston, Massachusetts, USA,02115
| | - O. Oner
- Department of Child and Adolescent Psychiatry, Dr Sami Ulus Childrens’ Hospital, Telsizler, Ankara, Turkey
| | - S. Al-Saad
- Kuwait Center for Autism, Kuwait City, Kuwait
| | | | - L. Bastaki
- Kuwait Medical Genetics Center, Kuwait City, Kuwait
| | - T. Ben-Omran
- Section of Clinical and Metabolic Genetics, Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar
- Departments of Pediatrics and Genetic Medicine, Weil-Cornell Medical College, New York and Doha, Qatar
| | - A. Teebi
- Section of Clinical and Metabolic Genetics, Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar
- Departments of Pediatrics and Genetic Medicine, Weil-Cornell Medical College, New York and Doha, Qatar
| | - L. Al-Gazali
- Department of Paediatrics, Faculty of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - V. Eapen
- Academic Unit of Child Psychiatry South West Sydney (AUCS), University of New South Wales, Sydney, New South Wales, Australia
| | - C.R. Stevens
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, Massachusetts, USA, 02142
| | - L. Rappaport
- The Autism Consortium, Boston, Massachusetts, USA, 02115
- Harvard Medical School, Boston, Massachusetts, USA, 02115
- Division of Developmental Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
| | - S.B. Gabriel
- Program in Medical and Population Genetics, Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, Massachusetts, USA, 02142
| | - K. Markianos
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Harvard Medical School, Boston, Massachusetts, USA, 02115
| | - M.W. State
- Department of Genetics, Center for Human Genetics and Genomics and Program on Neurogenetics, Yale University School of Medicine, New Haven, Connecticut, USA, 06510
| | - M.E. Greenberg
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, USA, 02115
| | - H. Taniguchi
- Institute for Enzyme Research, The University of Tokushima, Tokushima, Japan
| | - N.E. Braverman
- Department of Human Genetics and Pediatrics, McGill University, Montreal Children’s Hospital Research Institute, Montreal, Quebec, Canada, H3H1P3
| | - E.M. Morrow
- The Autism Consortium, Boston, Massachusetts, USA, 02115
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island, 02912
- Department of Psychiatry and Human Behavior, Brown University, Providence, Rhode Island, 02912
| | - C.A. Walsh
- Division of Genetics, Department of Medicine, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Manton Center for Orphan Disease Research, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts, USA, 02115
- The Autism Consortium, Boston, Massachusetts, USA, 02115
- Harvard Medical School, Boston, Massachusetts, USA, 02115
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Athanasakis E, Fabretto A, Faletra F, Mocenigo M, Morgan A, Gasparini P. Two Novel COH1 Mutations in an Italian Patient with Cohen Syndrome. Mol Syndromol 2012; 3:30-33. [PMID: 22855652 DOI: 10.1159/000338816] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/03/2012] [Indexed: 11/19/2022] Open
Abstract
Cohen syndrome (CS) is an autosomal recessive disease caused by mutations in the COH1 gene. It is characterized by intellectual disability, hypotonia, joint hyperlaxity, severe myopia, characteristic facial dysmorphisms and, in some cases, intermittent isolated neutropenia. We investigated an Italian patient with CS together with his family. Genetic analysis disclosed 2 novel mutations: the first is an intronic mutation (c.8697-9A>G) creating a new splice site 8 nucleotides upstream, and the second is a duplication of 1 base (c.10156dupA) generating a premature stop codon. The compound heterozygous mutations explain the proband's phenotype and improved the knowledge of genotype-phenotype correlation.
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Affiliation(s)
- E Athanasakis
- Institute for Maternal and Child Health, IRCCS 'Burlo Garofolo', Italy
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Novel C16orf57 mutations in patients with Poikiloderma with Neutropenia: bioinformatic analysis of the protein and predicted effects of all reported mutations. Orphanet J Rare Dis 2012; 7:7. [PMID: 22269211 PMCID: PMC3315733 DOI: 10.1186/1750-1172-7-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 01/23/2012] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Poikiloderma with Neutropenia (PN) is a rare autosomal recessive genodermatosis caused by C16orf57 mutations. To date 17 mutations have been identified in 31 PN patients. RESULTS We characterize six PN patients expanding the clinical phenotype of the syndrome and the mutational repertoire of the gene. We detect the two novel C16orf57 mutations, c.232C>T and c.265+2T>G, as well as the already reported c.179delC, c.531delA and c.693+1G>T mutations. cDNA analysis evidences the presence of aberrant transcripts, and bioinformatic prediction of C16orf57 protein structure gauges the mutations effects on the folded protein chain. Computational analysis of the C16orf57 protein shows two conserved H-X-S/T-X tetrapeptide motifs marking the active site of a two-fold pseudosymmetric structure recalling the 2H phosphoesterase superfamily. Based on this model C16orf57 is likely a 2H-active site enzyme functioning in RNA processing, as a presumptive RNA ligase. According to bioinformatic prediction, all known C16orf57 mutations, including the novel mutations herein described, impair the protein structure by either removing one or both tetrapeptide motifs or by destroying the symmetry of the native folding.Finally, we analyse the geographical distribution of the recurrent mutations that depicts clusters featuring a founder effect. CONCLUSIONS In cohorts of patients clinically affected by genodermatoses with overlapping symptoms, the molecular screening of C16orf57 gene seems the proper way to address the correct diagnosis of PN, enabling the syndrome-specific oncosurveillance. The bioinformatic prediction of the C16orf57 protein structure denotes a very basic enzymatic function consistent with a housekeeping function. Detection of aberrant transcripts, also in cells from PN patients carrying early truncated mutations, suggests they might be translatable. Tissue-specific sensitivity to the lack of functionally correct protein accounts for the main cutaneous and haematological clinical signs of PN patients.
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