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Schneider S, De Cegli R, Nagarajan J, Kretschmer V, Matthiessen PA, Intartaglia D, Hotaling N, Ueffing M, Boldt K, Conte I, May-Simera HL. Loss of Ciliary Gene Bbs8 Results in Physiological Defects in the Retinal Pigment Epithelium. Front Cell Dev Biol 2021; 9:607121. [PMID: 33681195 PMCID: PMC7930748 DOI: 10.3389/fcell.2021.607121] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 01/12/2021] [Indexed: 11/17/2022] Open
Abstract
Primary cilia are sensory organelles vital for developmental and physiological processes. Their dysfunction causes a range of phenotypes including retinopathies. Although primary cilia have been described in the retinal pigment epithelium (RPE), little is known about their contribution to biological processes within this tissue. Ciliary proteins are increasingly being identified in non-ciliary locations and might carry out additional functions, disruption of which possibly contributes to pathology. The RPE is essential for maintaining photoreceptor cells and visual function. We demonstrate that upon loss of Bbs8, predominantly thought to be a ciliary gene, the RPE shows changes in gene and protein expression initially involved in signaling pathways and developmental processes, and at a later time point RPE homeostasis and function. Differentially regulated molecules affecting the cytoskeleton and cellular adhesion, led to defective cellular polarization and morphology associated with a possible epithelial-to-mesenchymal transition (EMT)-like phenotype. Our data highlights the benefit of combinatorial “omics” approaches with in vivo data for investigating the function of ciliopathy proteins. It also emphasizes the importance of ciliary proteins in the RPE and their contribution to visual disorders, which must be considered when designing treatment strategies for retinal degeneration.
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Affiliation(s)
- Sandra Schneider
- Faculty of Biology, Institute of Molecular Physiology, Johannes Gutenberg-University, Mainz, Germany
| | | | - Jayapriya Nagarajan
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, United States
| | - Viola Kretschmer
- Faculty of Biology, Institute of Molecular Physiology, Johannes Gutenberg-University, Mainz, Germany
| | - Peter Andreas Matthiessen
- Faculty of Biology, Institute of Molecular Physiology, Johannes Gutenberg-University, Mainz, Germany
| | | | - Nathan Hotaling
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, United States
| | - Marius Ueffing
- Medical Bioanalytics, Institute for Ophthalmic Research, Eberhard-Karls University, Tübingen, Germany
| | - Karsten Boldt
- Medical Bioanalytics, Institute for Ophthalmic Research, Eberhard-Karls University, Tübingen, Germany
| | - Ivan Conte
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy.,Department of Biology, University of Naples Federico II, Naples, Italy
| | - Helen Louise May-Simera
- Faculty of Biology, Institute of Molecular Physiology, Johannes Gutenberg-University, Mainz, Germany
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202
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BBS Proteins Affect Ciliogenesis and Are Essential for Hedgehog Signaling, but Not for Formation of iPSC-Derived RPE-65 Expressing RPE-Like Cells. Int J Mol Sci 2021; 22:ijms22031345. [PMID: 33572860 PMCID: PMC7866284 DOI: 10.3390/ijms22031345] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/23/2021] [Accepted: 01/24/2021] [Indexed: 12/31/2022] Open
Abstract
Bardet-Biedl syndrome (BBS) is a ciliopathy characterized by retinal dystrophy, renal cysts, obesity and polydactyly. BBS genes have been implicated in ciliogenesis, hedgehog signaling and retinal pigment epithelium maturation. BBS1 and BBS5 are members of the BBSome, implicated in cilia transport of proteins, and BBS10 is a member of the chaperonin-complex, mediating BBSome assembly. In this study, involvement of BBS1, BBS5 and BBS10 in ciliogenesis and hedgehog signaling were investigated in BBS-defective patient fibroblasts as well as in RPE-hTERT cells following siRNA-mediated knockdown of the BBS genes. Furthermore, the ability of BBS1-defective induced pluripotent stem-cells (iPSCs) to differentiate into RPE cells was assessed. We report that cells lacking functional BBS5 or BBS10 have a reduced number of primary cilia, whereas cells lacking functional BBS1 display shorter primary cilia compared to wild-type cells. Hedgehog signaling was substantially impaired and Smoothened, a component of hedgehog signaling, was trapped inside the cilia of the BBS-defective cells, even in the absence of Smoothened agonist. Preliminary results demonstrated the ability of BBS1-defective iPSC to differentiate into RPE-65 expressing RPE-like cells. The BBS1-/--defective RPE-like cells were less pigmented, compared to RPE-like cells differentiated from control iPSCs, indicating an impact of BBS1 on RPE maturation.
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203
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Duan S, Li H, Zhang Y, Yang S, Chen Y, Qiu B, Huang C, Wang J, Li J, Zhu X, Yan X. Rabl2 GTP hydrolysis licenses BBSome-mediated export to fine-tune ciliary signaling. EMBO J 2021; 40:e105499. [PMID: 33241915 PMCID: PMC7809784 DOI: 10.15252/embj.2020105499] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 10/19/2020] [Accepted: 10/23/2020] [Indexed: 01/04/2023] Open
Abstract
Cilia of higher animals sense various environmental stimuli. Proper ciliary signaling requires appropriate extent of BBSome-mediated export of membrane receptors across ciliary barrier transition zone (TZ) through retrograde intraflagellar transport (IFT) machinery. How the barrier passage is controlled, however, remains unknown. Here, we show that small GTPase Rabl2 functions as a molecular switch for the outward TZ passage. Rabl2-GTP enters cilia by binding to IFT-B complex. Its GTP hydrolysis enables the outward TZ passage of the BBSome and its cargos with retrograde IFT machinery, whereas its persistent association leads to their shedding from IFT-B during the passing process and consequently ciliary retention. Rabl2 deficiency or expression of a GTP-locked mutant impairs the ciliary hedgehog signaling without interfering with ciliation and respectively results in different spectrums of mouse developmental disorders. We propose that the switch role of Rabl2 ensures proper turnover of the BBSome and ciliary membrane receptors to fine-tune cilia-dependent signaling for normal embryonic development and organismic homeostasis.
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Affiliation(s)
- Shichao Duan
- State Key Laboratory of Cell BiologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
- Department of PathologyFirst Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Hao Li
- State Key Laboratory of Cell BiologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Yirong Zhang
- State Key Laboratory of Cell BiologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Suming Yang
- State Key Laboratory of Cell BiologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Yawen Chen
- State Key Laboratory of Cell BiologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Benhua Qiu
- State Key Laboratory of Cell BiologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Cheng Huang
- State Key Laboratory of Cell BiologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Juan Wang
- State Key Laboratory of Cell BiologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Jinsong Li
- State Key Laboratory of Cell BiologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
| | - Xueliang Zhu
- State Key Laboratory of Cell BiologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghaiChina
- University of Chinese Academy of SciencesBeijingChina
- School of Life ScienceHangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhouChina
| | - Xiumin Yan
- State Key Laboratory of Cell BiologyShanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghaiChina
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204
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Novel Compound Heterozygous BBS2 and Homozygous MKKS Variants Detected in Chinese Families with Bardet-Biedl Syndrome. J Ophthalmol 2021; 2021:6751857. [PMID: 33520300 PMCID: PMC7817241 DOI: 10.1155/2021/6751857] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 10/23/2020] [Accepted: 12/19/2020] [Indexed: 11/29/2022] Open
Abstract
Background Bardet–Biedl syndrome (BBS) is a rare multisystem developmental disorder. In this study, we report the genetic causes and clinical manifestations in two Chinese families with BBS. Materials and Methods Two families were recruited in this study. Family A was a four-generation family with four affected and 15 unaffected members participating in the study, and family B was a consanguineous family with one affected and three unaffected members participating. Whole exome sequencing was performed in the two families, followed by a multistep bioinformatics analysis. Sanger sequencing was used to verify the variants and to perform a segregation analysis. Comprehensive ocular and systemic examinations were also conducted. Results Novel compound heterozygous variants c.235T > G (p.T79P) and c.534 + 1G > T were detected in the BBS2 gene in family A, and known homozygous variant c.748G > A (p.G250R) was detected in the MKKS gene in family B. Both families presented with retinitis pigmentosa; however, except for polydactyly, all other systemic manifestations were different. All of the affected family members in family A were overweight with a high body mass index (range from 26.5 to 41.9) and high blood pressure. Family A also presented with a delay in the onset of secondary sex characteristics and genital anomalies, while other systemic abnormalities were absent in family B. Conclusions This study presents one family with two novel BBS2 variants, expanding the variant spectrum of BBS, and one family with a known homozygous MKKS variant. The different phenotypes seen between the families with BBS2 and MKKS variants will contribute to the literature and our overall understanding of BBS.
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205
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Dormegny L, Velizarova R, Schroder CM, Kilic-Huck U, Comtet H, Dollfus H, Bourgin P, Ruppert E. Sleep-Disordered Breathing, Quality of Sleep and Chronotype in a Cohort of Adult Patients with Bardet-Biedl Syndrome. Nat Sci Sleep 2021; 13:1913-1919. [PMID: 34720600 PMCID: PMC8550541 DOI: 10.2147/nss.s320660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 07/16/2021] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVE/BACKGROUND Bardet-Biedl syndrome (BBS) is a rare but well-recognized ciliopathy with high genetic and phenotypic heterogeneity. Cardinal features include obesity, diabetes and high blood pressure (HBP), which are often associated with sleep-disordered breathing. Also, the high prevalence of blindness due to retinal dystrophy could affect circadian sleep-wake rhythms. We characterized in this cohort of adult BBS patients sleep-disordered breathing, sleep quality, daytime sleepiness and chronotype. PATIENTS AND METHODS Thirty-two patients with genetically confirmed BBS were included in this observational single center study. Overnight respiratory polygraphy was performed for sleep apnea syndrome (SAS) in 30 patients. Quality of sleep, daytime sleepiness, fatigue and chronotype were assessed in 25 patients using Pittsburgh sleep quality index (PSQI), 14-day sleep diary (SD), Epworth sleepiness scale (ESS), Pichot fatigue scale (PFS) and Horne and Ostberg morningness-eveningness questionnaire (MEQ). RESULTS Patients' mean age was 32±11 years and mean BMI 32.6±7.7 kg/m2. Eleven (35%) patients had HBP and 7 (22%) diabetes. Moderate to severe sleep apnea syndrome (SAS) was present in 5 (17%) and was not associated with altered sleep, daytime sleepiness or fatigue. Most of the patients (63%) evaluated their sleep as of good quality (PSQI ≤ 5). Median scores of sleep quality, daytime sleepiness and fatigue were normal (PSQI of 3.0 [2.0-6.0], ESS of 9.0 [6.0-13.0] and PFS of 8.0 [3.0-13.0], respectively). Predominant chronotypes according to MEQ were either "intermediate" (57%) or "moderate morning" (29%). None had a free running sleep-wake cycle. 14-day SD revealed overall few awakenings at night and low daytime napping. CONCLUSIONS Given the cardiovascular risk factors, systematic screening for SAS should be considered in BBS patients, regardless of sleep and daytime vigilance complaints. None of these highly visually impaired patients had a circadian sleep-wake rhythm disorder. Further objective assessments are needed to better characterize sleep and circadian rhythms in BBS patients.
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Affiliation(s)
- Léa Dormegny
- Centre des Troubles du Sommeil - CIRCSom, Hôpital Civil, University of Strasbourg, Strasbourg, 67091, France.,Department of Ophthalmology, Hôpital Civil, University of Strasbourg, Strasbourg, 67091, France
| | - Reana Velizarova
- Centre des Troubles du Sommeil - CIRCSom, Hôpital Civil, University of Strasbourg, Strasbourg, 67091, France
| | - Carmen M Schroder
- Centre des Troubles du Sommeil - CIRCSom, Hôpital Civil, University of Strasbourg, Strasbourg, 67091, France.,Institute for Cellular and Integrative Neurosciences, CNRS - UPR 3212, Strasbourg, 67000, France
| | - Ulker Kilic-Huck
- Centre des Troubles du Sommeil - CIRCSom, Hôpital Civil, University of Strasbourg, Strasbourg, 67091, France.,Institute for Cellular and Integrative Neurosciences, CNRS - UPR 3212, Strasbourg, 67000, France
| | - Henri Comtet
- Centre des Troubles du Sommeil - CIRCSom, Hôpital Civil, University of Strasbourg, Strasbourg, 67091, France.,Institute for Cellular and Integrative Neurosciences, CNRS - UPR 3212, Strasbourg, 67000, France
| | - Hélène Dollfus
- Centre des Affections Rares en Génétique Ophtalmologique (CARGO), University of Strasbourg, Strasbourg, 67091, France
| | - Patrice Bourgin
- Centre des Troubles du Sommeil - CIRCSom, Hôpital Civil, University of Strasbourg, Strasbourg, 67091, France.,Institute for Cellular and Integrative Neurosciences, CNRS - UPR 3212, Strasbourg, 67000, France
| | - Elisabeth Ruppert
- Centre des Troubles du Sommeil - CIRCSom, Hôpital Civil, University of Strasbourg, Strasbourg, 67091, France.,Institute for Cellular and Integrative Neurosciences, CNRS - UPR 3212, Strasbourg, 67000, France
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206
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McKnight I, Hart C, Park IH, Shim JW. Genes causing congenital hydrocephalus: Their chromosomal characteristics of telomere proximity and DNA compositions. Exp Neurol 2021; 335:113523. [PMID: 33157092 PMCID: PMC7750280 DOI: 10.1016/j.expneurol.2020.113523] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 10/10/2020] [Accepted: 10/30/2020] [Indexed: 01/06/2023]
Abstract
Congenital hydrocephalus (CH) is caused by genetic mutations, but whether factors impacting human genetic mutations are disease-specific remains elusive. Given two factors associated with high mutation rates, we reviewed how many disease-susceptible genes match with (i) proximity to telomeres or (ii) high adenine and thymine (A + T) content in human CH as compared to other disorders of the central nervous system (CNS). We extracted genomic information using a genome data viewer. Importantly, 98 of 108 genes causing CH satisfied (i) or (ii), resulting in >90% matching rate. However, such a high accordance no longer sustained as we checked two factors in Alzheimer's disease (AD) and/or familial Parkinson's disease (fPD), resulting in 84% and 59% matching, respectively. A disease-specific matching of telomere proximity or high A + T content predicts causative genes of CH much better than neurodegenerative diseases and other CNS conditions, likely due to sufficient number of known causative genes (n = 108) and precise determination and classification of the genotype and phenotype. Our analysis suggests a need for identifying genetic basis of both factors before human clinical studies, to prioritize putative genes found in preclinical models into the likely (meeting at least one) and more likely candidate (meeting both), which predisposes human genes to mutations.
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Affiliation(s)
- Ian McKnight
- Department of Biomedical Engineering, Marshall University, Huntington, WV 25755, USA
| | - Christoph Hart
- Department of Biomedical Engineering, Marshall University, Huntington, WV 25755, USA
| | - In-Hyun Park
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06519, USA
| | - Joon W Shim
- Department of Biomedical Engineering, Marshall University, Huntington, WV 25755, USA.
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207
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Dehani M, Zare-Abdollahi D, Bushehri A, Dehghani A, Effati J, Miratashi SAM, Khorram Khorshid HR. Identification of a Novel Homozygous Mutation in BBS10 Gene in an Iranian Family with Bardet-Biedl Syndrome. Avicenna J Med Biotechnol 2021; 13:230-233. [PMID: 34900151 PMCID: PMC8606112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 05/03/2021] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Bardet-Biedl Syndrome (BBS) is a rare pleiotropic autosomal recessive disease related to ciliopathies with approximately 25 causative genes. BBS is a multisystemic disorder with wide spectrum of manifestations including truncal obesity, retinal dystrophy, male hypogenitalism, postaxial polydactyly, learning difficulties, and renal abnormalities. METHODS A consanguineous Iranian family with a 28-year-old daughter affected with BBS, resulting from a first cousin marriage, was examined. After clinical examination, Whole Exome Sequencing (WES) was applied. Following the analysis of exome data, Sanger sequencing was used to confirm as well as to co-segregate the candidate variant with the phenotype. RESULTS A novel homozygous variant [c. 2035G>A (p.E679K)] in exon 2 of the BBS10 gene was found which was categorized as likely pathogenic based on American College of Medical Genetics and Genomics (ACMG) guidelines and criteria. In this study, the variant was fully co-segregated with the phenotype in the family. CONCLUSION Despite overlapping with other ciliopathies in terms of the phenotype, the BBS has high genetic heterogeneity and clinical variability even among affected members of a family. The symptoms observed in patients are largely related to the genes involved and the type of mutations in the BBS. In this study, in addition to phenotype description of the proband harboring a novel disease-causing variant in BBS10 gene, the spectrum of BBS symptoms was expanded. The findings of this study can be useful in genetic counseling, especially for risk estimation and prenatal diagnosis.
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Affiliation(s)
- Mohammad Dehani
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Davood Zare-Abdollahi
- Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran,Corresponding author: Davood Zare-Abdollahi, Ph.D., Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran, Tel: +98 9138502360, Fax: +98 21 22180138, E-mail:
| | - Ata Bushehri
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Azadeh Dehghani
- Medical Biotechnology Research Center, Ashkezar Branch, Islamic Azad University, Ashkezar, Iran
| | - Jalil Effati
- Meybod Genetic Research Center, State Welfare Organization, Yazd, Iran
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208
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Oleari R, André V, Lettieri A, Tahir S, Roth L, Paganoni A, Eberini I, Parravicini C, Scagliotti V, Cotellessa L, Bedogni F, De Martini LB, Corridori MV, Gulli S, Augustin HG, Gaston-Massuet C, Hussain K, Cariboni A. A Novel SEMA3G Mutation in Two Siblings Affected by Syndromic GnRH Deficiency. Neuroendocrinology 2021; 111:421-441. [PMID: 32365351 DOI: 10.1159/000508375] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 05/01/2020] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Gonadotropin-releasing hormone (GnRH) deficiency causes hypogonadotropic hypogonadism (HH), a rare genetic disorder that impairs sexual reproduction. HH can be due to defective GnRH-secreting neuron development or function and may be associated with other clinical signs in overlapping genetic syndromes. With most of the cases being idiopathic, genetics underlying HH is still largely unknown. OBJECTIVE To assess the contribution of mutated Semaphorin 3G (SEMA3G) in the onset of a syndromic form of HH, characterized by intellectual disability and facial dysmorphic features. METHOD By combining homozygosity mapping with exome sequencing, we identified a novel variant in the SEMA3G gene. We then applied mouse as a model organism to examine SEMA3Gexpression and its functional requirement in vivo. Further, we applied homology modelling in silico and cell culture assays in vitro to validate the pathogenicity of the identified gene variant. RESULTS We found that (i) SEMA3G is expressed along the migratory route of GnRH neurons and in the developing pituitary, (ii) SEMA3G affects GnRH neuron development, but is redundant in the adult hypothalamic-pituitary-gonadal axis, and (iii) mutated SEMA3G alters binding properties in silico and in vitro to its PlexinA receptors and attenuates its effect on the migration of immortalized GnRH neurons. CONCLUSION In silico, in vitro, and in vivo models revealed that SEMA3G regulates GnRH neuron migration and that its mutation affecting receptor selectivity may be responsible for the HH-related defects.
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Affiliation(s)
- Roberto Oleari
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Valentina André
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Antonella Lettieri
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Sophia Tahir
- Genetics and Genomic Medicine Programme, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Lise Roth
- Division of Vascular Oncology and Metastasis, German Cancer Research Center (DKFZ-ZMBH Alliance), Heidelberg, Germany
| | - Alyssa Paganoni
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Ivano Eberini
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Chiara Parravicini
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Valeria Scagliotti
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Ludovica Cotellessa
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
- IRCCS Istituto Auxologico Italiano, Laboratory of Endocrine and Metabolic Research, Milan, Italy
| | - Francesco Bedogni
- San Raffaele Rett Research Unit, Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy
- Neuroscience and Mental Health Research Institute (NMHRI), Division of Neuroscience, School of Biosciences, Cardiff, United Kingdom
| | | | | | - Simona Gulli
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Hellmut G Augustin
- Division of Vascular Oncology and Metastasis, German Cancer Research Center (DKFZ-ZMBH Alliance), Heidelberg, Germany
- European Center for Angioscience (ECAS), Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Carles Gaston-Massuet
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - Khalid Hussain
- Sidra Medical & Research Center, Division of Endocrinology OPC, Department of Pediatric Medicine, Doha, Qatar
| | - Anna Cariboni
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy,
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209
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Abstract
Neural circuits in the hypothalamus play a key role in the regulation of human energy homeostasis. A critical circuit involves leptin-responsive neurons in the hypothalamic arcuate nucleus (the infundibular nucleus in humans) expressing the appetite-suppressing neuropeptide proopiomelanocortin (POMC) and the appetite-stimulating Agouti-related peptide. In the fed state, the POMC-derived melanocortin peptide α-melanocyte-stimulating hormone stimulates melanocortin-4 receptors (MC4Rs) expressed on second-order neurons in the paraventricular nucleus of the hypothalamus (PVN). Agonism of MC4R leads to reduced food intake and increased energy expenditure. Disruption of this hypothalamic circuit by inherited mutations in the genes encoding leptin, the leptin receptor, POMC, and MC4R can lead to severe obesity in humans. The characterization of these and closely related genetic obesity syndromes has informed our understanding of the neural pathways by which leptin regulates energy balance, neuroendocrine function, and the autonomic nervous system. A broader understanding of these neural and molecular mechanisms has paved the way for effective mechanism-based therapies for patients whose severe obesity is driven by disruption of these pathways.
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Affiliation(s)
- I Sadaf Farooqi
- Wellcome-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom.
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210
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Sablok A, Thakur S, Sharma A, Kaul A. Prenatal Diagnosis of Bardet-Biedl Syndrome: A Case Study and Review of Literature. JOURNAL OF FETAL MEDICINE 2020. [DOI: 10.1007/s40556-020-00278-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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211
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Koscinski I, Mark M, Messaddeq N, Braun JJ, Celebi C, Muller J, Zinetti-Bertschy A, Goetz N, Dollfus H, Rossignol S. Reproduction Function in Male Patients With Bardet Biedl Syndrome. J Clin Endocrinol Metab 2020; 105:dgaa551. [PMID: 32835378 PMCID: PMC7538103 DOI: 10.1210/clinem/dgaa551] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 08/12/2020] [Indexed: 12/23/2022]
Abstract
PURPOSE Bardet-Biedl syndrome (BBS) is a ciliopathy with a wide spectrum of symptoms due to primary cilia dysfunction, including genitourinary developmental anomalies as well as impaired reproduction, particularly in males. Primary cilia are known to be required at the following steps of reproduction function: (i) genitourinary organogenesis, (ii) in fetal firing of hypothalamo-pituitary axe, (iii) sperm flagellum structure, and (iv) first zygotic mitosis conducted by proximal sperm centriole. BBS phenotype is not fully understood. METHODS This study explored all steps of reproduction in 11 French male patients with identified BBS mutations. RESULTS BBS patients frequently presented with genitourinary malformations, such as cryptorchidism (5/11), short scrotum (5/8), and micropenis (5/8), but unexpectedly, with normal testis size (7/8). Ultrasonography highlighted epididymal cysts or agenesis of one seminal vesicle in some cases. Sexual hormones levels were normal in all patients except one. Sperm numeration was normal in 8 out of the 10 obtained samples. Five to 45% of sperm presented a progressive motility. Electron microscopy analysis of spermatozoa did not reveal any homogeneous abnormality. Moreover, a psychological approach pointed to a decreased self-confidence linked to blindness and obesity explaining why so few BBS patients express a child wish. CONCLUSIONS Primary cilia dysfunction in BBS impacts the embryology of the male genital tract, especially epididymis, penis, and scrotum through an insufficient fetal androgen production. However, in adults, sperm structure does not seem to be impacted. These results should be confirmed in a greater BBS patient cohort, focusing on fertility.
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Affiliation(s)
- Isabelle Koscinski
- Laboratoire de Biologie de la Reproduction/CECOS Lorraine, Hôpitaux universitaires de Nancy, Nancy, France
- Université de Lorraine, Inserm, NGERE, Nancy, France
| | - Manuel Mark
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch-Graffenstaden, France
- Laboratoire de Biologie de la Reproduction, Hôpitaux universitaires de Strasbourg (HUS), Strasbourg, France
| | - Nadia Messaddeq
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch-Graffenstaden, France
| | - Jean Jacques Braun
- Service ORL et CCF, Hôpitaux universitaires de Strasbourg (HUS), Strasbourg, France
| | - Catherine Celebi
- Laboratoire de Biologie de la Reproduction, Hôpitaux universitaires de Strasbourg (HUS), Strasbourg, France
| | - Jean Muller
- Laboratoire de Génétique Médicale, INSERM, UMRS_1112, Institut de Génétique Médicale d’Alsace (IGMA), Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Faculté de médecine de Strasbourg, Strasbourg, France
- Laboratoires de Diagnostic Génétique, Hôpitaux Universitaires de Strasbourg, Institut de Génétique Médicale d’Alsace (IGMA), Strasbourg, France
| | - Anna Zinetti-Bertschy
- Pôle de Psychiatrie, Santé Mentale et Addictologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
- Neuropsychologie cognitive et physiopathologie de la schizophrénie, Unité de recherche INSERM U1114, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Strasbourg, France
| | - Nathalie Goetz
- Filière SENSGENE, Centre de Référence pour les affections rares en génétique ophtalmologique (CARGO), Institut de Génétique Médicale d’Alsace (IGMA), Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Hélène Dollfus
- Laboratoire de Génétique Médicale, INSERM, UMRS_1112, Institut de Génétique Médicale d’Alsace (IGMA), Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Faculté de médecine de Strasbourg, Strasbourg, France
- Laboratoires de Diagnostic Génétique, Hôpitaux Universitaires de Strasbourg, Institut de Génétique Médicale d’Alsace (IGMA), Strasbourg, France
- Filière SENSGENE, Centre de Référence pour les affections rares en génétique ophtalmologique (CARGO), Institut de Génétique Médicale d’Alsace (IGMA), Hôpitaux Universitaires de Strasbourg, Strasbourg, France
- Service de Génétique Médicale, Hôpitaux Universitaires de Strasbourg, Institut de Génétique Médicale d’Alsace (IGMA), Strasbourg, France
| | - Sylvie Rossignol
- Laboratoire de Génétique Médicale, INSERM, UMRS_1112, Institut de Génétique Médicale d’Alsace (IGMA), Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Faculté de médecine de Strasbourg, Strasbourg, France
- Laboratoires de Diagnostic Génétique, Hôpitaux Universitaires de Strasbourg, Institut de Génétique Médicale d’Alsace (IGMA), Strasbourg, France
- Service de Génétique Médicale, Hôpitaux Universitaires de Strasbourg, Institut de Génétique Médicale d’Alsace (IGMA), Strasbourg, France
- Service de Pédiatrie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
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Gohil A, Eugster EA. Delayed and Precocious Puberty: Genetic Underpinnings and Treatments. Endocrinol Metab Clin North Am 2020; 49:741-757. [PMID: 33153677 PMCID: PMC7705597 DOI: 10.1016/j.ecl.2020.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Delayed puberty may signify a common variation of normal development, or indicate the presence of a pathologic process. Constitutional delay of growth and puberty is a strongly familial type of developmental pattern and accounts for the vast majority of children who are "late bloomers." Individuals with sex chromosomal abnormalities frequently have hypergonadotropic hypogonadism. There are currently 4 known monogenic causes of central precocious puberty. The primary treatment goal in children with hypogonadism is to mimic normal pubertal progression, while the primary aims for the management of precocious puberty are preservation of height potential and prevention of further pubertal development.
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Affiliation(s)
- Anisha Gohil
- Division of Pediatric Endocrinology, Department of Pediatrics, Riley Hospital for Children at IU Health, Indiana University School of Medicine, 705 Riley Hospital Drive, Room 5960, Indianapolis, IN 46202, USA.
| | - Erica A Eugster
- Division of Pediatric Endocrinology, Department of Pediatrics, Riley Hospital for Children at IU Health, Indiana University School of Medicine, 705 Riley Hospital Drive, Room 5960, Indianapolis, IN 46202, USA
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213
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Impact of Genetic Variations and Epigenetic Mechanisms on the Risk of Obesity. Int J Mol Sci 2020; 21:ijms21239035. [PMID: 33261141 PMCID: PMC7729759 DOI: 10.3390/ijms21239035] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 11/23/2020] [Accepted: 11/25/2020] [Indexed: 12/12/2022] Open
Abstract
Rare genetic obesity disorders are characterized by mutations of genes strongly involved in the central or peripheral regulation of energy balance. These mutations are effective in causing the early onset of severe obesity and insatiable hunger (hyperphagia), suggesting that the genetic component can contribute to 40–70% of obesity. However, genes’ roles in the processes leading to obesity are still unclear. This review is aimed to summarize the current knowledge of the genetic causes of obesity, especially monogenic obesity, describing the role of epigenetic mechanisms in obesity and metabolic diseases. A comprehensive understanding of the underlying genetic and epigenetic mechanisms, with the metabolic processes they control, will permit adequate management and prevention of obesity.
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214
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Islam S, Reddy UK, Natarajan P, Abburi VL, Bajwa AA, Imran M, Zahoor MY, Abdullah M, Bukhari AM, Iqbal S, Ashraf K, Nadeem A, Rehman H, Rashid I, Shehzad W. Population demographic history and population structure for Pakistani Nili-Ravi breeding bulls based on SNP genotyping to identify genomic regions associated with male effects for milk yield and body weight. PLoS One 2020; 15:e0242500. [PMID: 33232358 PMCID: PMC7685427 DOI: 10.1371/journal.pone.0242500] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 11/03/2020] [Indexed: 11/20/2022] Open
Abstract
The domestic Nili-Ravi water buffalo (Bubalus bubalis) is the best dairy animal contributing 68% to total milk production in Pakistan. In this study, we identified genome-wide single nucleotide polymorphisms (SNPs) to estimate various population genetic parameters such as diversity, pairwise population differentiation, linkage disequilibrium (LD) distribution and for genome-wide association study for milk yield and body weight traits in the Nili-Ravi dairy bulls that they may pass on to their daughters who are retained for milking purposes. The genotyping by sequencing approach revealed 13,039 reference genome-anchored SNPs with minor allele frequency of 0.05 among 167 buffalos. Population structure analysis revealed that the bulls were grouped into two clusters (K = 2), which indicates the presence of two different lineages in the Pakistani Nili-Ravi water buffalo population, and we showed the extent of admixture of these two lineages in our bull collection. LD analysis revealed 4169 significant SNP associations, with an average LD decay of 90 kb for these buffalo genome. Genome-wide association study involved a multi-locus mixed linear model for milk yield and body weight to identify genome-wide male effects. Our study further illustrates the utility of the genotyping by sequencing approach for identifying genomic regions to uncover additional demographic complexity and to improve the complex dairy traits of the Pakistani Nili-Ravi water buffalo population that would provide the lot of economic benefits to dairy industry.
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Affiliation(s)
- Saher Islam
- Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Umesh K. Reddy
- Department of Biology, West Virginia State University, Institute, West Virginia, United States of America
| | - Purushothaman Natarajan
- Department of Biology, West Virginia State University, Institute, West Virginia, United States of America
| | - Venkata Lakshmi Abburi
- Department of Biology, West Virginia State University, Institute, West Virginia, United States of America
| | - Amna Arshad Bajwa
- Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Muhammad Imran
- Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Muhammad Yasir Zahoor
- Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Muhammad Abdullah
- Department of Livestock Production, University of Veterinary and Animal Sciences, Pattoki, Pakistan
| | - Aamir Mehmood Bukhari
- Semen Production Unit, Qadirabad, District Sahiwal, Pakistan
- Livestock and Dairy Development Department, Government of the Punjab, Lahore, Pakistan
| | - Sajid Iqbal
- Semen Production Unit, Qadirabad, District Sahiwal, Pakistan
- Livestock and Dairy Development Department, Government of the Punjab, Lahore, Pakistan
| | - Kamran Ashraf
- Department of Parasitology, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Asif Nadeem
- Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Habibur Rehman
- Department of Physiology, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Imran Rashid
- Department of Parasitology, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Wasim Shehzad
- Institute of Biochemistry and Biotechnology, University of Veterinary and Animal Sciences, Lahore, Pakistan
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215
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Hosio M, Jaks V, Lagus H, Vuola J, Ogawa R, Kankuri E. Primary Ciliary Signaling in the Skin-Contribution to Wound Healing and Scarring. Front Cell Dev Biol 2020; 8:578384. [PMID: 33282860 PMCID: PMC7691485 DOI: 10.3389/fcell.2020.578384] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 10/08/2020] [Indexed: 12/21/2022] Open
Abstract
Primary cilia (PC) are solitary, post-mitotic, microtubule-based, and membrane-covered protrusions that are found on almost every mammalian cell. PC are specialized cellular sensory organelles that transmit environmental information to the cell. Signaling through PC is involved in the regulation of a variety of cellular processes, including proliferation, differentiation, and migration. Conversely, defective, or abnormal PC signaling can contribute to the development of various pathological conditions. Our knowledge of the role of PC in organ development and function is largely based on ciliopathies, a family of genetic disorders with mutations affecting the structure and function of PC. In this review, we focus on the role of PC in their major signaling pathways active in skin cells, and their contribution to wound healing and scarring. To provide comprehensive insights into the current understanding of PC functions, we have collected data available in the literature, including evidence across cell types, tissues, and animal species. We conclude that PC are underappreciated subcellular organelles that significantly contribute to both physiological and pathological processes of the skin development and wound healing. Thus, PC assembly and disassembly and PC signaling may serve as attractive targets for antifibrotic and antiscarring therapies.
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Affiliation(s)
- Mayu Hosio
- Faculty of Medicine, Department of Pharmacology, University of Helsinki, Helsinki, Finland
| | - Viljar Jaks
- Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
- Dermatology Clinic, Tartu University Hospital, Tartu, Estonia
| | - Heli Lagus
- Department of Plastic Surgery and Wound Healing Centre, Helsinki University Hospital, University of Helsinki, Helsinki, Finland
| | - Jyrki Vuola
- Helsinki University Hospital, University of Helsinki, Helsinki, Finland
| | - Rei Ogawa
- Department of Plastic, Reconstructive and Aesthetic Surgery, Nippon Medical School, Tokyo, Japan
| | - Esko Kankuri
- Faculty of Medicine, Department of Pharmacology, University of Helsinki, Helsinki, Finland
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216
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Kumar A, Husain A, Saleem A, Khawaja UA, Virani S. Laurence-Moon-Bardet-Biedl Syndrome: A Rare Case With a Literature Review. Cureus 2020; 12:e11355. [PMID: 33304690 PMCID: PMC7720918 DOI: 10.7759/cureus.11355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Laurence-Moon-Bardet-Biedl syndrome (LMBBS), a rare autosomal recessive genetic disorder, results from consanguineous marriage. It is a congenital ciliopathy manifesting with primary and secondary characteristics. Primary clinical features include rod and cone dystrophy, polydactyly, central obesity, genital abnormalities, and mental retardation, often presenting as poor schooling skills. Secondary clinical features include developmental delay, speech deficit, brachydactyly/syndactyly, dental defects, ataxia, olfactory deficit, diabetes mellitus (DM), and congenital heart disease. Herein, we report a case of a 15-year-old male with clinical manifestations of LMBBS, namely learning disabilities, night blindness, hypogonadism, polydactyly, polysyndactyly, and obesity. Physicians must be familiar with this syndrome, for which an early diagnosis, multidisciplinary approach, and regular follow-ups can profoundly diminish morbidity and mortality in LMBBS patients.
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Affiliation(s)
- Aneel Kumar
- Psychiatry and Behavioral Sciences, Jinnah Medical and Dental College, Karachi, PAK
| | - Aamir Husain
- Opthalmology, Jinnah Medical and Dental College, Karachi, PAK
| | - Amna Saleem
- Medicine and Surgery, Jinnah Medical and Dental College, Karachi, PAK
| | - Uzzam Ahmed Khawaja
- Internal Medicine, Jinnah Medical and Dental College, Karachi, PAK.,Clinical and Translational Research, Larkin Community Hospital, Miami, USA
| | - Sumaira Virani
- Medicine and Surgery, Jinnah Medical and Dental College, Karachi, PAK
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217
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Haws R, Brady S, Davis E, Fletty K, Yuan G, Gordon G, Stewart M, Yanovski J. Effect of setmelanotide, a melanocortin-4 receptor agonist, on obesity in Bardet-Biedl syndrome. Diabetes Obes Metab 2020; 22:2133-2140. [PMID: 32627316 PMCID: PMC7689750 DOI: 10.1111/dom.14133] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/25/2020] [Accepted: 06/30/2020] [Indexed: 12/16/2022]
Abstract
AIM To report an analysis of ~1 year of setmelanotide treatment for obesity and hunger, as well as metabolic and cardiac outcomes, in individuals with Bardet-Biedl syndrome (BBS). MATERIALS AND METHODS Individuals aged 12 years and older with BBS received once-daily setmelanotide. The dose was titrated every 2 weeks to establish the individual therapeutic dose (≤3 mg); treatment continued for an additional 10 weeks. Participants who lost 5 kg or more (or ≥5% of body weight if <100 kg at baseline) continued into the 52-week extension phase. The primary outcome was mean percent change from baseline in body weight at 3 months. Hunger scores and safety were secondary outcomes. RESULTS From February 2017 and February 2018, 10 individuals were screened; eight completed the 3-month treatment phase and seven completed the extension phase. Mean percent change in body weight from baseline to 3 months was -5.5% (90% CI, -9.3% to -1.6%; n = 8); change from baseline was -11.3% (90% CI, -15.5% to -7.0%; n = 8) at 6 months and -16.3% (90% CI, -19.9% to -12.8%; n = 7) at 12 months. All participants reported at least one treatment-emergent adverse event (AE), most commonly injection-site reaction. No AEs led to study withdrawal or death. Most, morning, and average hunger scores were reduced across time points. CONCLUSIONS Setmelanotide reduced body weight and hunger in individuals with BBS and had a safety profile consistent with previous reports. Setmelanotide may be a treatment option in individuals with BBS-associated obesity and hyperphagia.
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Affiliation(s)
- Robert Haws
- Marshfield Clinic Research InstituteMarshfieldWisconsinUSA
| | - Sheila Brady
- Section on Growth and ObesityEunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of HealthBethesdaMarylandUSA
| | - Elisabeth Davis
- Section on Growth and ObesityEunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of HealthBethesdaMarylandUSA
| | | | - Guojun Yuan
- Rhythm PharmaceuticalsBostonMassachusettsUSA
| | | | | | - Jack Yanovski
- Section on Growth and ObesityEunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of HealthBethesdaMarylandUSA
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218
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Next-Generation Sequencing in the Diagnosis of Patients with Bardet-Biedl Syndrome-New Variants and Relationship with Hyperglycemia and Insulin Resistance. Genes (Basel) 2020; 11:genes11111283. [PMID: 33138063 PMCID: PMC7693916 DOI: 10.3390/genes11111283] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/20/2020] [Accepted: 10/27/2020] [Indexed: 12/27/2022] Open
Abstract
Bardet-Biedl syndrome (BBS) is a rare autosomal recessively inherited disease with major clinical symptoms such as: obesity, retinal degeneration, polydactyly and renal abnormalities. The aim of the study was to assess the spectrum of gene variants among patients with BBS, identified on the basis of nationwide genetic studies of monogenic diabetes in Polish population. Out of 575 patients enrolled for genetic testing from February 2017 to July 2019, 25 patients with a clinical suspicion of BBS were selected. The identification of pathogenic variants was performed by using targeted next-generation sequencing (NGS) on Illumina NextSeq 550 platform involving the SureSelect assay (Agilent, Santa Clara, CA, USA). BBS was genetically confirmed in 10 of 25 suspected patients. In patients, 14 different variants were found in six genes, mainly in BBS9 and BBS10 gene, including two novel variants. A strong association between hyperglycemia and insulin resistance in patients and the presence of variants in BBS9 gene was observed. Identification of 14 variants, including two new mutations using the NGS method, is the first molecular characteristic of Polish patients with Bardet–Biedl syndrome. It gives hope for earlier proper diagnosis of BBS in future patients selected from children with early childhood obesity and their medical multidisciplinary care.
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219
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Jehan S, Zizi F, Pandi-Perumal SR, McFarlane SI, Jean-Louis G, Myers AK. Energy imbalance: obesity, associated comorbidities, prevention, management and public health implications. ADVANCES IN OBESITY, WEIGHT MANAGEMENT & CONTROL 2020; 10:146-161. [PMID: 33305001 PMCID: PMC7725222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The prevalence of obesity has been continually increasing, as have its associated comorbidities and health care costs. Effective management of obesity and early intervention measures are necessary to overcome this global issue. The responsibility for preventing and managing this global epidemic does not lie solely on an individual, but also on the entire health care system. Policy makers-nationally and globally-must play their roles to solve the issue. In this review article, we examine methods of controlling and managing obesity through interventions, such as a low caloric diet, physical exercise, pharmacological guidance, and bariatric surgical procedures. While health care professionals should educate patients about all available treatment options for severe obesity, bariatric surgical procedures have increased in popularity and are considered very beneficial with outcomes fruitful in managing severe obesity.
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Affiliation(s)
- Shazia Jehan
- Department of Population Health, Center for Healthful Behavior Change, USA
| | - Ferdinand Zizi
- Department of Population Health, Center for Healthful Behavior Change, USA
| | | | | | | | - Alyson K Myers
- Department of Internal Medicine, Division of Endocrinology, USA
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220
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Fan JR, You LR, Wang WJ, Huang WS, Chu CT, Chi YH, Chen HC. Lamin A-mediated nuclear lamina integrity is required for proper ciliogenesis. EMBO Rep 2020; 21:e49680. [PMID: 32815283 PMCID: PMC7534621 DOI: 10.15252/embr.201949680] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 07/12/2020] [Accepted: 07/23/2020] [Indexed: 01/10/2023] Open
Abstract
The primary cilium is a sensory organelle that receives specific signals from the extracellular environment important for vertebrate development and tissue homeostasis. Lamins, the major components of the nuclear lamina, are required to maintain the nuclear structure and are involved in most nuclear activities. In this study, we show that deficiency in lamin A/C causes defective ciliogenesis, accompanied by increased cytoplasmic accumulation of actin monomers and increased formation of actin filaments. Disruption of actin filaments by cytochalasin D rescues the defective ciliogenesis in lamin A/C-depleted cells. Moreover, lamin A/C-deficient cells display lower levels of nesprin 2 and defects in recruiting Arp2, myosin Va, and tau tubulin kinase 2 to the basal body during ciliogenesis. Collectively, our results uncover a functional link between nuclear lamina integrity and ciliogenesis and implicate the malfunction of primary cilia in the pathogenesis of laminopathy.
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Affiliation(s)
- Jia-Rong Fan
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan.,Cancer Progression Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Li-Ru You
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan.,Cancer Progression Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Won-Jing Wang
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Wei-Syun Huang
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Ching-Tung Chu
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Ya-Hui Chi
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhunan, Taiwan
| | - Hong-Chen Chen
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan.,Cancer Progression Research Center, National Yang-Ming University, Taipei, Taiwan
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221
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Crisóstomo L, Pereira SC, Monteiro MP, Raposo JF, Oliveira PF, Alves MG. Lifestyle, metabolic disorders and male hypogonadism - A one-way ticket? Mol Cell Endocrinol 2020; 516:110945. [PMID: 32707080 DOI: 10.1016/j.mce.2020.110945] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/27/2020] [Accepted: 07/06/2020] [Indexed: 12/15/2022]
Abstract
Hypogonadism is more frequent among men with common metabolic diseases, notably obesity and type 2 diabetes. Indeed, endocrine disruption caused by metabolic diseases can trigger the onset of hypogonadism, although the underlying molecular mechanisms are not entirely understood. Metabolic diseases are closely related to unhealthy lifestyle choices, such as dietary habits and sedentarism. Therefore, hypogonadism is part of a pathological triad gathering unhealthy lifestyle, metabolic disease and genetic background. Additionally, hypogonadism harbors the potential to aggravate underlying metabolic disorders, further sustaining the mechanisms leading to disease. To what extent does lifestyle intervention in men suffering from these metabolic disorders can prevent, improve or reverse hypogonadism, is still controversial. Moreover, recent evidence suggests that the metabolic status of the father is related to the risk of inter and transgenerational inheritance of hypogonadism. In this review, we will address the proposed mechanisms of disease, as well as currently available interventions for hypogonadism.
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Affiliation(s)
- Luís Crisóstomo
- Department of Microscopy, Laboratory of Cell Biology, And Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Portugal
| | - Sara C Pereira
- Department of Microscopy, Laboratory of Cell Biology, And Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Portugal
| | - Mariana P Monteiro
- Department of Anatomy, And Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Portugal
| | - João F Raposo
- NOVA Medical School - New University Lisbon, Lisbon, Portugal; APDP - Diabetes Portugal, Lisbon, Portugal
| | - Pedro F Oliveira
- QOPNA & LAQV, Department of Chemistry, University of Aveiro, Portugal
| | - Marco G Alves
- Department of Microscopy, Laboratory of Cell Biology, And Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Portugal.
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Abstract
Obesity represents a major health burden to both developed and developing countries. Furthermore, the incidence of obesity is increasing in children. Obesity contributes substantially to mortality in the United States by increasing the risk for type 2 diabetes, cardiovascular-related diseases, and other comorbidities. Despite environmental changes over past decades, including increases in high-calorie foods and sedentary lifestyles, there is very clear evidence of a genetic predisposition to obesity risk. Childhood obesity cases can be categorized in one of two ways: syndromic or non-syndromic. Syndromic obesity includes disorders such as Prader-Willi syndrome, Bardet-Biedl syndrome, and Alström syndrome. Non-syndromic cases of obesity can be further separated into rarer instances of monogenic obesity and much more common forms of polygenic obesity. The advent of genome-wide association studies (GWAS) and next-generation sequencing has driven significant advances in our understanding of the genetic contribution to childhood obesity. Many rare and common genetic variants have been shown to contribute to the heritability in obesity, although the molecular mechanisms underlying most of these variants remain unclear. An important caveat of GWAS efforts is that they do not strictly represent gene target discoveries, rather simply the uncovering of robust genetic signals. One clear example of this is with progress in understanding the key obesity signal harbored within an intronic region of the FTO gene. It has been shown that the non-coding region in which the variant actually resides in fact influences the expression of genes distal to FTO instead, specifically IRX3 and IRX5. Such discoveries suggest that associated non-coding variants can be embedded within or next to one gene, but commonly influence the expression of other, more distal effector genes. Advances in genetics and genomics are therefore contributing to a deeper understanding of childhood obesity, allowing for development of clinical tools and therapeutic agents.
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223
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Yaman F, Çekmen N. Anesthetic management of a patient with Bardet-Biedl syndrome undergoing renal transplantation: A case report. Medicine (Baltimore) 2020; 99:e22300. [PMID: 32957390 PMCID: PMC7505336 DOI: 10.1097/md.0000000000022300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Bardet-Biedl syndrome, which compromises airway management and the cardiovascular and renal systems, is a rare ciliopathic syndrome characterized by multisystem involvement and varying genetic etiologies and clinical manifestations. PATIENT CONCERNS A 13-year-old female patient had a history of chronic renal failure, hypothyroidism, mental retardation, hypogonadotropic hypogonadism, obesity, and retinitis pigmentosa and was undergoing 4-hour hemodialysis 3 days a week. DIAGNOSIS We diagnosed Bardet-Biedl syndrome based on the results of genetic tests. INTERVENTIONS We performed renal transplantation under general anesthesia while considering the perioperative risks of airway obstruction and hypothermia. OUTCOMES Multidisciplinary preoperative evaluation is crucial to avoid perioperative complications. The risk of an obstructed airway should be considered. Hypothyroidism is a rare consequence of Bardet-Biedl syndrome. Rocuronium and sugammadex are safe for anesthetic management during renal transplantation to address Bardet-Biedl syndrome. CONCLUSION Safe anesthetic management can be achieved with the rigorous preoperative assessment of perioperative complications.
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Affiliation(s)
- Ferda Yaman
- University of Eskişehir Osmangazi, Department of Anesthesiology and Reanimation, Faculty of Medicine, Eskişehir
| | - Nedim Çekmen
- Department of Anesthesiology and Reanimation, Istanbul Nisantasi University, İstanbul, Turkey
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224
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Deletion in the Bardet-Biedl Syndrome Gene TTC8 Results in a Syndromic Retinal Degeneration in Dogs. Genes (Basel) 2020; 11:genes11091090. [PMID: 32962042 PMCID: PMC7565673 DOI: 10.3390/genes11091090] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 09/12/2020] [Accepted: 09/15/2020] [Indexed: 02/06/2023] Open
Abstract
In golden retriever dogs, a 1 bp deletion in the canine TTC8 gene has been shown to cause progressive retinal atrophy (PRA), the canine equivalent of retinitis pigmentosa. In humans, TTC8 is also implicated in Bardet–Biedl syndrome (BBS). To investigate if the affected dogs only exhibit a non-syndromic PRA or develop a syndromic ciliopathy similar to human BBS, we recruited 10 affected dogs to the study. The progression of PRA for two of the dogs was followed for 2 years, and a rigorous clinical characterization allowed a careful comparison with primary and secondary characteristics of human BBS. In addition to PRA, the dogs showed a spectrum of clinical and morphological signs similar to primary and secondary characteristics of human BBS patients, such as obesity, renal anomalies, sperm defects, and anosmia. We used Oxford Nanopore long-read cDNA sequencing to characterize retinal full-length TTC8 transcripts in affected and non-affected dogs, the results of which suggest that three isoforms are transcribed in the retina, and the 1 bp deletion is a loss-of-function mutation, resulting in a canine form of Bardet–Biedl syndrome with heterogeneous clinical signs.
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225
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BBS4 Is Essential for Nuclear Transport of Transcription Factors Mediating Neuronal ER Stress Response. Mol Neurobiol 2020; 58:78-91. [PMID: 32894499 DOI: 10.1007/s12035-020-02104-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 08/27/2020] [Indexed: 11/09/2022]
Abstract
Bardet-Biedl syndrome (BBS) is an autosomal recessive syndrome presenting with retinal dystrophy, cognitive impairment, and obesity. BBS is characterized by elevated endoplasmic reticulum (ER) stress in the early stages of adipocyte and retinal development. BBS expression in the CNS and indications of hippocampal dysgenesis suggest neural development abnormalities. However, the role of BBS in ER stress in neuronal cells has not yet been studied. Therefore, we aimed at studying the role of BBS4 in neuronal development under normal and ER stress conditions. ER stress and unfolded protein response (UPR) were studied in BBS4-silenced (SiBBS4) SH-SY5Y cells during differentiation under normal and stress states, using molecular and biochemical markers. ER stress was demonstrated at early neural differentiation, with significantly augmented expression of UPR markers corresponding to BBS4 expression. In the undifferentiated state, BBS4 silencing resulted in significantly reduced ER-stress markers' expression under normal and ER-stress states. Independent of ER stress, SiBBS4 cells demonstrated significant reduction in activated phospho-IRE1α. Under BBS4 silencing, both sXBP-1 and activated ATF6α p50 failed to translocate to the nucleus. Transcript levels of apoptosis markers were upregulated under BBS4 depletion and ER-stress induction, corresponding to decreased viability. BBS4 depletion in neuronal cells results in reduced sensitivity to ER stress during differentiation and under ER-stress induction, partly due to failure in translocation of ER-transcription factors (TF) sXBP-1 and ATF6α p50 to the nucleus. Hence, BBS4 is essential for nuclear transport under ER-stress response in neuronal cells during early differentiation. Our studies shed light on molecular mechanisms through which BBS4 malfunction alters neuronal ER stress response.
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226
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Nees SN, Chung WK. Genetic Basis of Human Congenital Heart Disease. Cold Spring Harb Perspect Biol 2020; 12:cshperspect.a036749. [PMID: 31818857 DOI: 10.1101/cshperspect.a036749] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Congenital heart disease (CHD) is the most common major congenital anomaly with an incidence of ∼1% of live births and is a significant cause of birth defect-related mortality. The genetic mechanisms underlying the development of CHD are complex and remain incompletely understood. Known genetic causes include all classes of genetic variation including chromosomal aneuploidies, copy number variants, and rare and common single-nucleotide variants, which can be either de novo or inherited. Among patients with CHD, ∼8%-12% have a chromosomal abnormality or aneuploidy, between 3% and 25% have a copy number variation, and 3%-5% have a single-gene defect in an established CHD gene with higher likelihood of identifying a genetic cause in patients with nonisolated CHD. These genetic variants disrupt or alter genes that play an important role in normal cardiac development and in some cases have pleiotropic effects on other organs. This work reviews some of the most common genetic causes of CHD as well as what is currently known about the underlying mechanisms.
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Affiliation(s)
| | - Wendy K Chung
- Department of Pediatrics.,Department of Medicine, Columbia University Irving Medical Center, New York, New York 10032, USA
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227
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Branham K, Schlegel D, Fahim AT, Jayasundera KT. Genetic testing for inherited retinal degenerations: Triumphs and tribulations. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2020; 184:571-577. [PMID: 32865341 DOI: 10.1002/ajmg.c.31835] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 07/31/2020] [Accepted: 08/05/2020] [Indexed: 12/20/2022]
Abstract
Inherited retinal degenerations (IRDs) are a genotypically and phenotypically diverse group of conditions. Great strides have been made toward identifying the genetic basis for these conditions over the last 30 years-more than 270 different genes involved in syndromic and nonsyndromic forms of retinal dystrophies have now been identified. The identification of these genes and the improvement of clinical laboratory techniques have led to the identification of the genetic basis of disease in 56-76% of patients with IRDs through next generation sequencing and copy number variant analysis. Genetic testing is an essential part of clinical care for patients affected with IRDs and is required to confirm the diagnosis, understand the inheritance of the condition, and determine eligibility for gene-specific treatments or clinical trials. Despite the success achieved in determining the genetic cause of these conditions, several challenges remain, which must be considered when providing genetic testing and genetic counseling to patients. For this reason, an integrated team of ophthalmic and genetic clinicians who are familiar with these challenges is necessary to provide optimal comprehensive care to these patients.
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Affiliation(s)
- Kari Branham
- Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan, USA
| | - Dana Schlegel
- Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan, USA
| | - Abigail T Fahim
- Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan, USA
| | - K Thiran Jayasundera
- Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan, USA
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228
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Prasai A, Schmidt Cernohorska M, Ruppova K, Niederlova V, Andelova M, Draber P, Stepanek O, Huranova M. The BBSome assembly is spatially controlled by BBS1 and BBS4 in human cells. J Biol Chem 2020; 295:14279-14290. [PMID: 32759308 DOI: 10.1074/jbc.ra120.013905] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 08/04/2020] [Indexed: 12/18/2022] Open
Abstract
Bardet-Biedl syndrome (BBS) is a pleiotropic ciliopathy caused by dysfunction of primary cilia. More than half of BBS patients carry mutations in one of eight genes encoding for subunits of a protein complex, the BBSome, which mediates trafficking of ciliary cargoes. In this study, we elucidated the mechanisms of the BBSome assembly in living cells and how this process is spatially regulated. We generated a large library of human cell lines deficient in a particular BBSome subunit and expressing another subunit tagged with a fluorescent protein. We analyzed these cell lines utilizing biochemical assays, conventional and expansion microscopy, and quantitative fluorescence microscopy techniques: fluorescence recovery after photobleaching and fluorescence correlation spectroscopy. Our data revealed that the BBSome formation is a sequential process. We show that the pre-BBSome is nucleated by BBS4 and assembled at pericentriolar satellites, followed by the translocation of the BBSome into the ciliary base mediated by BBS1. Our results provide a framework for elucidating how BBS-causative mutations interfere with the biogenesis of the BBSome.
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Affiliation(s)
- Avishek Prasai
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Marketa Schmidt Cernohorska
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Klara Ruppova
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Veronika Niederlova
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Monika Andelova
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Peter Draber
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Ondrej Stepanek
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Martina Huranova
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
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229
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Bales KL, Bentley MR, Croyle MJ, Kesterson RA, Yoder BK, Gross AK. BBSome Component BBS5 Is Required for Cone Photoreceptor Protein Trafficking and Outer Segment Maintenance. Invest Ophthalmol Vis Sci 2020; 61:17. [PMID: 32776140 PMCID: PMC7441369 DOI: 10.1167/iovs.61.10.17] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 07/15/2020] [Indexed: 01/07/2023] Open
Abstract
Purpose To identify the role of the BBSome protein Bardet-Biedl syndrome 5 (BBS5) in photoreceptor function, protein trafficking, and structure using a congenital mutant mouse model. Methods Bbs5-/- mice (2 and 9 months old) were used to assess retinal function and morphology. Hematoxylin and eosin staining of retinal sections was performed to visualize histology. Electroretinography was used to analyze rod and cone photoreceptor function. Retinal protein localization was visualized using immunofluorescence (IF) within retinal cryosections. TUNEL staining was used to quantify cell death. Transmission electron microscopy (TEM) was used to examine retinal ultrastructure. Results In the Bbs5-/- retina, there was a significant loss of nuclei in the outer nuclear layer accompanied by an increase in cell death. Through electroretinography, Bbs5-/- mice showed complete loss of cone photoreceptor function. IF revealed mislocalization of the cone-specific proteins M- and S-opsins, arrestin-4, CNGA3, and GNAT2, as well as a light-dependent arrestin-1 mislocalization, although perpherin-2 was properly localized. TEM revealed abnormal outer segment disk orientation in Bbs5-/-. Conclusions Collectively, these data suggest that, although BBS5 is a core BBSome component expressed in all ciliated cells, its role within the retina mediates specific photoreceptor protein cargo transport. In the absence of BBS5, cone-specific protein mislocalization and a loss of cone photoreceptor function occur.
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Affiliation(s)
- Katie L. Bales
- Department of Optometry and Vision Sciences, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Melissa R. Bentley
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Mandy J. Croyle
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Robert A. Kesterson
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Bradley K. Yoder
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Alecia K. Gross
- Department of Optometry and Vision Sciences, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Department of Neurobiology, University of Alabama at Birmingham, Birmingham, Alabama, United States
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230
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Gumus E, Tuncez E, Oz O, Saka Guvenc M. Clinical and exome sequencing findings in seven children with Bardet-Biedl syndrome from Turkey. Ann Hum Genet 2020; 85:27-36. [PMID: 32686083 DOI: 10.1111/ahg.12401] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 07/02/2020] [Accepted: 07/02/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND Bardet-Biedl syndrome (BBS) is a very-rare autosomal recessive genetic disorder with severe multisystem manifestations. Genetic testing plays an important role in the early diagnosis of the disease. In this study, while trying to elucidate the genetic etiology of seven individuals with clinical BBS diagnosis from six different families, we also aimed to examine the distribution of BBS variations in this region of Turkey. METHODS AND MATERIALS Exome sequencing analysis is performed for clinically diagnosed patients with BBS in the present study followed by parental segregation. The unreported and previously described clinical features are presented. RESULTS Homozygous variants, four of which are unreported, in BBS-related genes (BBS5 [c.682-2A > G], MKKS [c.775del], BBS7 [c.849+1G > T], BBS9 [c.965G > A], BBS10 [c.145C > T], LZTFL1[c.384G > A]) are detected for all the seven individuals included in the study. The most common clinical finding is polydactyly followed by renal anomalies. The clinical features not previously described are correlated to the unreported variant. CONCLUSIONS In this study, exome sequencing findings are discussed and four previously unreported disease-associated variants are described including the fifth BBS-implicated LZTFL1 change and possible genotype-phenotype correlation is described.
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Affiliation(s)
- Evren Gumus
- Department of Medical Genetics, Faculty of Medicine, University of Harran, Sanliurfa, Turkey.,Department of Medical Genetics, Faculty of Medicine, University of Mugla Sitki Kocman, Mugla, Turkey
| | - Ebru Tuncez
- Clinic of Medical Genetics, Sanliurfa Training and Research Hospital, Sanliurfa, Turkey
| | - Ozlem Oz
- Department of Medical Genetics, Faculty of Medicine, University of Harran, Sanliurfa, Turkey
| | - Merve Saka Guvenc
- Genetic Diagnosis Center, Tepecik Training and Research Hospital, University of Health Sciences, Izmir, Turkey
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231
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Zhang CJ, Xiang L, Chen XJ, Wang XY, Wu KC, Zhang BW, Chen DF, Jin GH, Zhang H, Chen YC, Liu WQ, Li ML, Ma Y, Jin ZB. Ablation of Mature miR-183 Leads to Retinal Dysfunction in Mice. Invest Ophthalmol Vis Sci 2020; 61:12. [PMID: 32176259 PMCID: PMC7401733 DOI: 10.1167/iovs.61.3.12] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Purpose The microRNA cluster miR-183C, which includes miR-183 and two other genes, is critical for multiple sensory systems. In mouse retina, removal of this cluster results in photoreceptor defects in polarization, phototransduction, and outer segment elongation. However, the individual roles of the three components of this cluster are not clearly known. We studied the separate role of mouse miR-183 in in vivo. Methods miR-183 knockout mice were generated using the CRISPR/Cas9 genome-editing system. Electroretinography were carried out to investigate the changes of retinal structures and function. miR-183 was overexpressed by subretinal adeno-associated virus (AAV) injection in vivo. Rnf217, a target of miR-183 was overexpressed by cell transfection of the photoreceptor-derived cell line 661W in vitro. RNA sequencing and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to compare the gene expression changes in AAV-injected mice and transfected cells. Results The miR-183 knockout mice showed progressively attenuated electroretinogram responses. Over- or under-expression of Rnf217, a direct target of miR-183, misregulated expression of cilia-related BBSome genes. Rnf217 overexpression also led to compromised electroretinography responses in WT mice, indicating that it may contribute to functional abnormalities in miR-183 knockout mice. Conclusions miR-183 is essential for mouse retinal function mediated directly and indirectly through Rnf217 and cilia-related genes. Our findings provide valuable insights into the explanation and analysis of the regulatory role of the individual miR-183 in miR-183C.
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232
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Wormser O, Levy Y, Bakhrat A, Bonaccorsi S, Graziadio L, Gatti M, AbuMadighem A, McKenney RJ, Okada K, El Riati S, Har-Vardi I, Huleihel M, Levitas E, Birk OS, Abdu U. Absence of SCAPER causes male infertility in humans and Drosophila by modulating microtubule dynamics during meiosis. J Med Genet 2020; 58:254-263. [PMID: 32527956 PMCID: PMC10405349 DOI: 10.1136/jmedgenet-2020-106946] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 04/22/2020] [Accepted: 04/25/2020] [Indexed: 12/25/2022]
Abstract
BACKGROUND Mutation in S-phase cyclin A-associated protein rin the endoplasmic reticulum (SCAPER) have been found across ethnicities and have been shown to cause variable penetrance of an array of pathological traits, including intellectual disability, retinitis pigmentosa and ciliopathies. METHODS Human clinical phenotyping, surgical testicular sperm extraction and testicular tissue staining. Generation and analysis of short spindle 3 (ssp3) (SCAPER orthologue) Drosophila CAS9-knockout lines. In vitro microtubule (MT) binding assayed by total internal reflection fluorescence microscopy. RESULTS We show that patients homozygous for a SCAPER mutation lack SCAPER expression in spermatogonia (SPG) and are azoospermic due to early defects in spermatogenesis, leading to the complete absence of meiotic cells. Interestingly, Drosophila null mutants for the ubiquitously expressed ssp3 gene are viable and female fertile but male sterile. We further show that male sterility in ssp3 null mutants is due to failure in both chromosome segregation and cytokinesis. In cells undergoing male meiosis, the MTs emanating from the centrosomes do not appear to interact properly with the chromosomes, which remain dispersed within dividing spermatocytes (SPCs). In addition, mutant SPCs are unable to assemble a normal central spindle and undergo cytokinesis. Consistent with these results, an in vitro assay demonstrated that both SCAPER and Ssp3 directly bind MTs. CONCLUSIONS Our results show that SCAPER null mutations block the entry into meiosis of SPG, causing azoospermia. Null mutations in ssp3 specifically disrupt MT dynamics during male meiosis, leading to sterility. Moreover, both SCAPER and Ssp3 bind MTs in vitro. These results raise the intriguing possibility of a common feature between human and Drosophila meiosis.
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Affiliation(s)
- Ohad Wormser
- The Morris Kahn Laboratory of Human Genetics, National Institute for Biotechnology in the Negev and Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Ygal Levy
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Anna Bakhrat
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Silvia Bonaccorsi
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza University of Rome, Rome, Italy
| | - Lucia Graziadio
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza University of Rome, Rome, Italy
| | - Maurizio Gatti
- Dipartimento di Biologia e Biotecnologie "C. Darwin", Sapienza University of Rome, Rome, Italy.,Istituto di Biologia e Patologia Molecolari Consiglio Nazionale delle Ricerche, Roma, Italy
| | - Ali AbuMadighem
- Shraga Segal Department of Microbiology, Immunology and Genetics, Ben-Gurion University of the Negev Faculty of Health Sciences, Beer-Sheva, Israel.,The Center of Advanced Research and Education in Reproduction (CARER), Ben-Gurion University of the Negev Faculty of Health Sciences, Beer-Sheva, Israel
| | - Richard J McKenney
- Department of Molecular and Cellular Biology, UC Davis, Davis, California, USA
| | - Kyoko Okada
- Department of Molecular and Cellular Biology, UC Davis, Davis, California, USA
| | - Saad El Riati
- Southern District, Clalit Health Services, Beer-Sheva, Israel
| | - Iris Har-Vardi
- The Center of Advanced Research and Education in Reproduction (CARER), Ben-Gurion University of the Negev Faculty of Health Sciences, Beer-Sheva, Israel.,Fertility and IVF Unit, Department of Obstetrics and Gynecology, Soroka University Medical Center, Beer-Sheva, Israel
| | - Mahmoud Huleihel
- Shraga Segal Department of Microbiology, Immunology and Genetics, Ben-Gurion University of the Negev Faculty of Health Sciences, Beer-Sheva, Israel.,The Center of Advanced Research and Education in Reproduction (CARER), Ben-Gurion University of the Negev Faculty of Health Sciences, Beer-Sheva, Israel
| | - Eliahu Levitas
- The Center of Advanced Research and Education in Reproduction (CARER), Ben-Gurion University of the Negev Faculty of Health Sciences, Beer-Sheva, Israel.,Fertility and IVF Unit, Department of Obstetrics and Gynecology, Soroka University Medical Center, Beer-Sheva, Israel
| | - Ohad S Birk
- The Morris Kahn Laboratory of Human Genetics, National Institute for Biotechnology in the Negev and Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel .,Genetics Institute, Soroka University Medical Center, Beer-Sheva, Israel
| | - Uri Abdu
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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233
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Tao T, Wang L, Chong W, Yang L, Li G. Characteristics of genotype and phenotype in Chinese patients with Bardet-Biedl syndrome. Int Ophthalmol 2020; 40:2325-2343. [PMID: 32448990 DOI: 10.1007/s10792-020-01415-3] [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: 01/07/2020] [Accepted: 05/02/2020] [Indexed: 12/31/2022]
Abstract
PURPOSE To investigate complex and different phenotypes in seven Chinese patients diagnosed with Bardet-Biedl syndrome (BBS) and carrying pathogenic mutations. METHODS Seven unrelated BBS patients were enrolled. Their medical and ophthalmic histories were reviewed, and comprehensive clinical examinations, such as fundus photography, optical coherence tomography, and medical imaging, were performed. A specific hereditary eye disease enrichment panel based on exome-capture technology was used to collect and amplify the protein-coding regions of 441 targeted hereditary eye disease genes, followed by high-throughput sequencing using the Illumina HiSeq platform. RESULTS All patients exhibited the primary clinical phenotype of BBS. Seven BBS mutations were found in five patients (BBS7 in two patients, BBS10 in two patients, BBS12 in one patient), for a detection rate of 71% (5/7). The ratio of novel to known BBS mutations was 5:2. CONCLUSIONS This study showed the phenotypic and genotypic spectrum of BBS patients from China, and the findings underscore the importance of obtaining comprehensive clinical observations and molecular analyses for ciliopathies.
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Affiliation(s)
- Tianchang Tao
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, People's Republic of China
| | - Lei Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, People's Republic of China
| | - Weihua Chong
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, People's Republic of China
| | - Liping Yang
- Department of Ophthalmology, Peking University Third Hospital, Key Laboratory of Restoration of Damaged Ocular Nerve Beijing, Beijing, People's Republic of China
| | - Genlin Li
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, People's Republic of China.
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234
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Jiman OA, Taylor RL, Lenassi E, Smith JC, Douzgou S, Ellingford JM, Barton S, Hardcastle C, Fletcher T, Campbell C, Ashworth J, Biswas S, Ramsden SC, Manson FD, Black GC. Diagnostic yield of panel-based genetic testing in syndromic inherited retinal disease. Eur J Hum Genet 2020; 28:576-586. [PMID: 31836858 PMCID: PMC7171123 DOI: 10.1038/s41431-019-0548-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 10/22/2019] [Accepted: 10/29/2019] [Indexed: 01/22/2023] Open
Abstract
Thirty percent of all inherited retinal disease (IRD) is accounted for by conditions with extra-ocular features. This study aimed to establish the genetic diagnostic pick-up rate for IRD patients with one or more extra-ocular features undergoing panel-based screening in a clinical setting. One hundred and six participants, tested on a gene panel which contained both isolated and syndromic IRD genes, were retrospectively ascertained from the Manchester Genomic Diagnostics Laboratory database spanning 6 years (2012-2017). Phenotypic features were extracted from the clinical notes and classified according to Human Phenotype Ontology; all identified genetic variants were interpreted in accordance to the American College of Medical Genetics and Genomics guidelines. Overall, 49% (n = 52) of patients received a probable genetic diagnosis. A further 6% (n = 6) had a single disease-associated variant in an autosomal recessive disease-relevant gene. Fifty-two percent (n = 55) of patients had a clinical diagnosis at the time of testing. Of these, 71% (n = 39) received a probable genetic diagnosis. By contrast, for those without a provisional clinical diagnosis (n = 51), only 25% (n = 13) received a probable genetic diagnosis. The clinical diagnosis of Usher (n = 33) and Bardet-Biedl syndrome (n = 10) was confirmed in 67% (n = 22) and 80% (n = 8), respectively. The testing diagnostic rate in patients with clinically diagnosed multisystemic IRD conditions was significantly higher than those without one (71% versus 25%; p value < 0.001). The lower pick-up rate in patients without a clinical diagnosis suggests that panel-based approaches are unlikely to be the most effective means of achieving a molecular diagnosis for this group. Here, we suggest that genome-wide approaches (whole exome or genome) are more appropriate.
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Affiliation(s)
- Omamah A Jiman
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Department of Genetic Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Rachel L Taylor
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Eva Lenassi
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Jill Clayton Smith
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Sofia Douzgou
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Jamie M Ellingford
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Stephanie Barton
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Claire Hardcastle
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Tracy Fletcher
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Christopher Campbell
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Jane Ashworth
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Royal Eye Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Susmito Biswas
- Manchester Royal Eye Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Simon C Ramsden
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Forbes D Manson
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
| | - Graeme C Black
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK.
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK.
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235
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Kops SA, Kylat RI, Bhatia S, Seckeler MD, Barber BJ, Bader MY. Genetic Characterization of a Model Ciliopathy: Bardet-Biedl Syndrome. J Pediatr Genet 2020; 10:126-130. [PMID: 33996183 DOI: 10.1055/s-0040-1708844] [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: 01/06/2020] [Accepted: 02/13/2020] [Indexed: 10/24/2022]
Abstract
Bardet-Biedl syndrome (BBS) is a rare ciliopathy affecting multiple organ systems. Patients with BBS are usually diagnosed later in childhood when clinical features of the disease become apparent. In this article, we presented a case of BBS discovered by whole genome sequencing in a newborn with heterotaxy, duodenal atresia, and complex congenital heart disease. Early diagnosis is important not only for prognostication but also to explore ways to mitigate the cone-rod dysfunction and for exploring newer therapies. Our case highlights the importance of a high index of suspicion and the utility of advanced genetic testing to provide an early diagnosis for a rare disease.
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Affiliation(s)
- Samantha A Kops
- Department of Pediatrics, Banner University Medical Center, Arizona, United States
| | - Ranjit I Kylat
- Department of Pediatrics, Banner University Medical Center, Arizona, United States.,Department of Pediatrics, University of Arizona College of Medicine, Arizona, United States
| | - Shanti Bhatia
- Department of Pediatrics, Banner University Medical Center, Arizona, United States
| | - Michael D Seckeler
- Department of Pediatrics, Banner University Medical Center, Arizona, United States.,Department of Pediatrics, University of Arizona College of Medicine, Arizona, United States
| | - Brent J Barber
- Department of Pediatrics, Banner University Medical Center, Arizona, United States.,Department of Pediatrics, University of Arizona College of Medicine, Arizona, United States
| | - Mohammad Y Bader
- Department of Pediatrics, Banner University Medical Center, Arizona, United States.,Department of Pediatrics, University of Arizona College of Medicine, Arizona, United States
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236
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Shaukat M, Ishaq T, Muhammad N, Naz S. RIN2 and BBS7 variants as cause of a coincidental syndrome. Eur J Med Genet 2020; 63:103755. [DOI: 10.1016/j.ejmg.2019.103755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 07/21/2019] [Accepted: 09/08/2019] [Indexed: 11/28/2022]
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237
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Goyal S, Singh IR, Vanita V. Novel mutation in MKKS/BBS6 linked with arRP and polydactyly in a family of North Indian origin. Clin Exp Ophthalmol 2020; 48:343-355. [PMID: 31989739 DOI: 10.1111/ceo.13719] [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: 04/11/2019] [Revised: 11/12/2019] [Accepted: 11/20/2019] [Indexed: 11/28/2022]
Abstract
BACKGROUND To identify the underlying genetic defect in a fourth-generation autosomal recessive retinitis pigmentosa (arRP) family. Detailed family history and clinical data were collected from nine members, including three affected, from an arRP family. METHODS Whole-exome sequencing (WES) was performed on DNA sample of an affected individual IV: 2. Variants obtained by WES were annotated using Ion Reporter Software (ver. 5.2). Potential pathogenic variants detected in an affected member were validated in other affected and unaffected family members by Sanger sequencing. Further 150 ethnically-matched controls were tested for the variant that co-segregated completely with disease in the family, so as to exclude it as a polymorphism. Various web-based bioinformatics tools were also applied to access pathogenic potential of the observed variant. RESULTS All the three patients had RP with polydactyly of both hands and feet, however, they did not show other symptoms of Bardet-Biedl syndrome (BBS) or McKusick-Kaufmann Syndrome (MKKS). A novel missense mutation, that is, c.518A>C (p.His173Pro) was identified in MKKS/BBS6 that co-segregated completely with the disease phenotype in all the three affected members and was not observed in six unaffected members of the family. Also the c.518A>C change was not observed in 150 ethnically matched controls (300 chromosomes), hence excluding it as a polymorphism. CONCLUSIONS Present study is the second report of identifying a novel mutation in MKKS/BBS6 that is linked with arRP in association with polydactyly, however, with no other signs of BBS or MKKS. These findings further expand the mutation spectrum of MKKS/BBS6 for arRP with polydactyly.
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Affiliation(s)
- Shiwali Goyal
- Department of Human Genetics, Guru Nanak Dev University, Amritsar, India
| | | | - Vanita Vanita
- Department of Human Genetics, Guru Nanak Dev University, Amritsar, India
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238
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Chakrabarty S, Savantre SB, Ramachandra Bhat C, Satyamoorthy K. Multiple genetic mutations implicate spectrum of phenotypes in Bardet-Biedl syndrome. Gene 2020; 725:144164. [PMID: 31639430 DOI: 10.1016/j.gene.2019.144164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 09/14/2019] [Accepted: 10/08/2019] [Indexed: 11/17/2022]
Abstract
Bardet-Biedl syndrome (BBS) is a clinically and genetically heterogeneous ciliopathy with several clinical features including retinitis pigmentosa, obesity, kidney dysfunction, postaxial polydactyly, behavioral dysfunction and hypogonadism with wide spectrum of additional features. With multiple phenotypes and heterogeneous distribution, it is unlikely that BBS is caused by single gene defect. We have performed clinical and genetic diagnosis of two individuals from an Indian family with classical BBS symptoms. Whole exome sequencing identified homozygous missense mutation in BBS10 gene, hemizygous missense AR and homozygous missense PDE6B mutations in the proband and affected sibling with BBS. Identification of BBS10 mutation along with AR and PDE6B gene mutation will expand the genetic and phenotypic spectrum in individuals with BBS.
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Affiliation(s)
- Sanjiban Chakrabarty
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
| | - Swheta B Savantre
- Department of Medicine, K.V.G. Medical College & Hospital, Dakshina Kannada, Sullia 574327, India
| | - C Ramachandra Bhat
- Department of Medicine, K.V.G. Medical College & Hospital, Dakshina Kannada, Sullia 574327, India
| | - Kapaettu Satyamoorthy
- Department of Cell and Molecular Biology, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India.
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239
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Zelihić D, Hjardemaal FR, Lippe CVD. Caring for a child with Bardet-Biedl syndrome: A qualitative study of the parental experiences of daily coping and support. Eur J Med Genet 2020; 63:103856. [PMID: 31972368 DOI: 10.1016/j.ejmg.2020.103856] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 12/12/2019] [Accepted: 01/17/2020] [Indexed: 10/25/2022]
Abstract
This study aimed to explore the parental experiences of having a child with Bardet-Biedl syndrome (BBS) and how parents managed to cope with this situation. Five parents of children with BBS (0-18 years old) participated in semistructured in-depth interviews. Inductive thematic analysis was used to identify themes. The parents experienced distress due to a lack of knowledge on BBS in their support system (e.g., school staff, clinicians, and family members), and they found it stressful to coordinate with multiple support services. Socialization at work, support from family members, and communicating with other parents who are in a similar situation promoted better coping and adaptations to daily life. Results highlight the importance of parents receiving adequate support while they face daily challenges. An increased knowledge on how rare disorders impact family life is needed in the support system.
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Affiliation(s)
- Deniz Zelihić
- Centre for Rare Disorders, Rikshospitalet, Oslo University Hospital HF, Norway
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240
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Patnaik SR, Farag A, Brücker L, Volz AK, Schneider S, Kretschmer V, May-Simera HL. Tissue-dependent differences in Bardet-Biedl syndrome gene expression. Biol Cell 2020; 112:39-52. [PMID: 31845361 DOI: 10.1111/boc.201900077] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 11/20/2019] [Accepted: 11/28/2019] [Indexed: 12/24/2022]
Abstract
BACKGROUND INFORMATION Primary cilia are highly conserved multifunctional cell organelles that extend from the cell membrane. A range of genetic disorders, collectively termed ciliopathies, is attributed to primary cilia dysfunction. The archetypical ciliopathy is the Bardet-Biedl syndrome (BBS), patients of which display virtually all symptoms associated with dysfunctional cilia. The primary cilium acts as a sensory organelle transmitting intra- and extracellular signals thereby transducing various signalling pathways facilitated by the BBS proteins. Growing evidence suggests that cilia proteins also have alternative functions in ciliary independent mechanisms, which might be contributing to disease etiology. RESULTS In an attempt to gain more insight into possible differences in organ specific roles, we examined whether relative gene expression for individual Bbs genes was constant across different tissues in mouse, in order to distinguish possible differences in organ specific roles. All tested tissues show differentially expressed Bbs transcripts with some tissues showing a more similar stoichiometric composition of transcripts than others do. However, loss of Bbs6 or Bbs8 affects expression of other Bbs transcripts in a tissue-dependent way. CONCLUSIONS AND SIGNIFICANCE Our data support the hypothesis that in some organs, BBS proteins not only function in a complex but might also have alternative functions in a ciliary independent context. This significantly alters our understanding of disease pathogenesis and development of possible treatment strategies.
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Affiliation(s)
- Sarita Rani Patnaik
- Cilia Cell Biology, Institute of Molecular Physiology, Johannes-Gutenberg University, Mainz, 55128, Germany
| | - Aalaa Farag
- Cilia Cell Biology, Institute of Molecular Physiology, Johannes-Gutenberg University, Mainz, 55128, Germany
| | - Lena Brücker
- Cilia Cell Biology, Institute of Molecular Physiology, Johannes-Gutenberg University, Mainz, 55128, Germany
| | - Ann-Kathrin Volz
- Cilia Cell Biology, Institute of Molecular Physiology, Johannes-Gutenberg University, Mainz, 55128, Germany
| | - Sandra Schneider
- Cilia Cell Biology, Institute of Molecular Physiology, Johannes-Gutenberg University, Mainz, 55128, Germany
| | - Viola Kretschmer
- Cilia Cell Biology, Institute of Molecular Physiology, Johannes-Gutenberg University, Mainz, 55128, Germany
| | - Helen Louise May-Simera
- Cilia Cell Biology, Institute of Molecular Physiology, Johannes-Gutenberg University, Mainz, 55128, Germany
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241
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Supekar B, Tomar S, Chopkar A, Mukhi J, Singh RP. Bardet–Biedl syndrome with café-au-lait macule: Association or coincidence? Indian Dermatol Online J 2020; 11:246-249. [PMID: 32477991 PMCID: PMC7247639 DOI: 10.4103/idoj.idoj_106_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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242
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Horiuchi K, Kogiso T, Sagawa T, Ito T, Taniai M, Miura K, Hattori M, Morisada N, Hashimoto E, Tokushige K. Bardet-Biedl Syndrome Caused by Skipping of SCLT1 Complicated by Microvesicular Steatohepatitis. Intern Med 2020; 59:2719-2724. [PMID: 33132306 PMCID: PMC7691027 DOI: 10.2169/internalmedicine.5045-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
We treated the case of a 22-year-old male patient with liver dysfunction. At 1 year of age, hepatic fibrosis was suspected. In addition, due to the presence of retinitis pigmentosa, renal failure, obesity, mental retardation, and hypogonadism, he was diagnosed with Bardet-Biedl syndrome (BBS). Skipping of exons 14 and 17 in the sodium channel and clathrin linker 1 (SCLT1) gene was observed. At 22 years of age, the liver enzyme levels were further elevated and a diagnosis of microvesicular steatohepatitis was made. Insulin resistance, a reduction of muscle mass, an impairment of the fatty acid metabolism, and hyperleptinemia in this syndrome may cause steatohepatitis.
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Affiliation(s)
- Kentaro Horiuchi
- Institute of Gastroenterology, Department of Internal Medicine, Tokyo Women's Medical University, Japan
| | - Tomomi Kogiso
- Institute of Gastroenterology, Department of Internal Medicine, Tokyo Women's Medical University, Japan
| | - Takaomi Sagawa
- Institute of Gastroenterology, Department of Internal Medicine, Tokyo Women's Medical University, Japan
| | - Taito Ito
- Institute of Gastroenterology, Department of Internal Medicine, Tokyo Women's Medical University, Japan
| | - Makiko Taniai
- Institute of Gastroenterology, Department of Internal Medicine, Tokyo Women's Medical University, Japan
| | - Kenichiro Miura
- Department of Pediatric Nephrology, Tokyo Women's Medical University, Japan
| | - Motoshi Hattori
- Department of Pediatric Nephrology, Tokyo Women's Medical University, Japan
| | - Naoya Morisada
- Department of Pediatrics, Kobe University Graduate School of Medicine, Japan
| | | | - Katsutoshi Tokushige
- Institute of Gastroenterology, Department of Internal Medicine, Tokyo Women's Medical University, Japan
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243
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A novel missense variant in the BBS7 gene underlying Bardet-Biedl syndrome in a consanguineous Pakistani family. Clin Dysmorphol 2020; 29:17-23. [DOI: 10.1097/mcd.0000000000000294] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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244
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Pazour GJ, Quarmby L, Smith AO, Desai PB, Schmidts M. Cilia in cystic kidney and other diseases. Cell Signal 2019; 69:109519. [PMID: 31881326 DOI: 10.1016/j.cellsig.2019.109519] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 12/21/2019] [Accepted: 12/21/2019] [Indexed: 12/23/2022]
Abstract
Epithelial cells lining the ducts and tubules of the kidney nephron and collecting duct have a single non-motile cilium projecting from their surface into the lumen of the tubule. These organelles were long considered vestigial remnants left as a result of evolution from a ciliated ancestor, but we now recognize them as critical sensory antennae. In the kidney, the polycystins and fibrocystin, products of the major human polycystic kidney disease genes, localize to this organelle. The polycystins and fibrocystin, through an unknown mechanism, monitor the diameter of the kidney tubules and regulate the proliferation and differentiation of the cells lining the tubule. When the polycystins, fibrocystin or cilia themselves are defective, the cell perceives this as a pro-proliferative signal, which leads to tubule dilation and cystic disease. In addition to critical roles in preventing cyst formation in the kidney, cilia are also important in cystic and fibrotic diseases of the liver and pancreas, and ciliary defects lead to a variety of developmental abnormalities that cause structural birth defects in most organs.
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Affiliation(s)
- Gregory J Pazour
- Program in Molecular Medicine, University of Massachusetts Medical School, Biotech II, Suite 213, 373 Plantation Street, Worcester, MA 01605, United States of America.
| | - Lynne Quarmby
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.
| | - Abigail O Smith
- Program in Molecular Medicine, University of Massachusetts Medical School, Biotech II, Suite 213, 373 Plantation Street, Worcester, MA 01605, United States of America
| | - Paurav B Desai
- Program in Molecular Medicine, University of Massachusetts Medical School, Biotech II, Suite 213, 373 Plantation Street, Worcester, MA 01605, United States of America
| | - Miriam Schmidts
- Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Freiburg University Faculty of Medicine, Mathildenstrasse 1, 79112 Freiburg, Germany.
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245
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Jaffal L, Joumaa WH, Assi A, Helou C, Cherfan G, Zibara K, Audo I, Zeitz C, El Shamieh S. Next Generation Sequencing Identifies Five Novel Mutations in Lebanese Patients with Bardet-Biedl and Usher Syndromes. Genes (Basel) 2019; 10:genes10121047. [PMID: 31888296 PMCID: PMC6947157 DOI: 10.3390/genes10121047] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 12/10/2019] [Accepted: 12/10/2019] [Indexed: 01/15/2023] Open
Abstract
AIM To identify disease-causing mutations in four Lebanese families: three families with Bardet-Biedl and one family with Usher syndrome (BBS and USH respectively), using next generation sequencing (NGS). METHODS We applied targeted NGS in two families and whole exome sequencing (WES) in two other families. Pathogenicity of candidate mutations was evaluated according to frequency, conservation, in silico prediction tools, segregation with disease, and compatibility with inheritance pattern. The presence of pathogenic variants was confirmed via Sanger sequencing followed by segregation analysis. RESULTS Most likely disease-causing mutations were identified in all included patients. In BBS patients, we found (M1): c.2258A > T, p. (Glu753Val) in BBS9, (M2): c.68T > C; p. (Leu23Pro) in ARL6, (M3): c.265_266delTT; p. (Leu89Valfs*11) and (M4): c.880T > G; p. (Tyr294Asp) in BBS12. A previously known variant (M5): c.551A > G; p. (Asp184Ser) was also detected in BBS5. In the USH patient, we found (M6): c.188A > C, p. (Tyr63Ser) in CLRN1. M2, M3, M4, and M6 were novel. All of the candidate mutations were shown to be likely disease-causing through our bioinformatic analysis. They also segregated with the corresponding phenotype in available family members. CONCLUSION This study expanded the mutational spectrum and showed the genetic diversity of BBS and USH. It also spotlighted the efficiency of NGS techniques in revealing mutations underlying clinically and genetically heterogeneous disorders.
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Affiliation(s)
- Lama Jaffal
- Department of Biological and Environmental Sciences, Faculty of Science, Beirut Arab University, Debbieh 1107 2809, Lebanon;
| | - Wissam H Joumaa
- Rammal Hassan Rammal Research Laboratory, Physiotoxicity (PhyTox), Faculty of Sciences, Lebanese University, Nabatieh 1700, Lebanon;
| | - Alexandre Assi
- Retinal Service, Beirut Eye & ENT Specialist Hospital, Beirut 1106, Lebanon; (A.A.); (C.H.); (G.C.)
| | - Charles Helou
- Retinal Service, Beirut Eye & ENT Specialist Hospital, Beirut 1106, Lebanon; (A.A.); (C.H.); (G.C.)
| | - George Cherfan
- Retinal Service, Beirut Eye & ENT Specialist Hospital, Beirut 1106, Lebanon; (A.A.); (C.H.); (G.C.)
| | - Kazem Zibara
- ER045, PRASE, DSST, Lebanese University, Beirut 1700, Lebanon;
- Biology Department, Faculty of Sciences-I, Lebanese University, Beirut 1700, Lebanon
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France; (I.A.); (C.Z.)
- CHNO des Quinze-Vingts, INSERM-DGOS CIC1423, 75012 Paris, France
- University College London Institute of Ophthalmology, London EC1V 9EL, UK
| | - Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France; (I.A.); (C.Z.)
| | - Said El Shamieh
- Rammal Hassan Rammal Research Laboratory, Physiotoxicity (PhyTox), Faculty of Sciences, Lebanese University, Nabatieh 1700, Lebanon;
- Department of Medical Laboratory Technology, Faculty of Health Sciences, Beirut Arab University, Beirut 1107 2809, Lebanon
- Correspondence:
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246
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ERICH3 in Primary Cilia Regulates Cilium Formation and the Localisations of Ciliary Transport and Sonic Hedgehog Signaling Proteins. Sci Rep 2019; 9:16519. [PMID: 31712586 PMCID: PMC6848114 DOI: 10.1038/s41598-019-52830-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 10/23/2019] [Indexed: 01/05/2023] Open
Abstract
Intraflagellar transport (IFT) is essential for the formation and function of the microtubule-based primary cilium, which acts as a sensory and signalling device at the cell surface. Consisting of IFT-A/B and BBSome cargo adaptors that associate with molecular motors, IFT transports protein into (anterograde IFT) and out of (retrograde IFT) the cilium. In this study, we identify the mostly uncharacterised ERICH3 protein as a component of the mammalian primary cilium. Loss of ERICH3 causes abnormally short cilia and results in the accumulation of IFT-A/B proteins at the ciliary tip, together with reduced ciliary levels of retrograde transport regulators, ARL13B, INPP5E and BBS5. We also show that ERICH3 ciliary localisations require ARL13B and BBSome components. Finally, ERICH3 loss causes positive (Smoothened) and negative (GPR161) regulators of sonic hedgehog signaling (Shh) to accumulate at abnormally high levels in the cilia of pathway-stimulated cells. Together, these findings identify ERICH3 as a novel component of the primary cilium that regulates cilium length and the ciliary levels of Shh signaling molecules. We propose that ERICH3 functions within retrograde IFT-associated pathways to remove signaling proteins from cilia.
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Generation and characterization of three isogenic induced pluripotent stem cell lines from a patient with Bardet-Biedl syndrome and homozygous for the BBS5 variant. Stem Cell Res 2019; 41:101594. [PMID: 31760295 DOI: 10.1016/j.scr.2019.101594] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 09/15/2019] [Accepted: 09/19/2019] [Indexed: 11/22/2022] Open
Abstract
Bardet-Biedl syndrome (BBS), an autosomal recessive disease, is associated with non-functional primary cilia. BBS5 is part of the protein complex termed the BBSome. The BBSome associates with intra flagellar transport (IFT) particles and mediates trafficking of membrane proteins in the cilium, a process important for cilia-mediated signal transduction. Here we describe the generation of three induced pluripotent stem cell (iPSC) lines, KCi003-A, KCi003-B and KCi003-C from a patient with BBS and homozygous for the disease causing variant c.214G>A, p.(Gly72Ser) in BBS5. The iPSC lines can be used for investigation of IFT in different cell types differentiated from the iPSC line.
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248
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Matheson BE, Colborn D, Bohon C. Bariatric Surgery in Children and Adolescents with Cognitive Impairment and/or Developmental Delay: Current Knowledge and Clinical Recommendations. Obes Surg 2019; 29:4114-4126. [DOI: 10.1007/s11695-019-04219-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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249
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de Herder W. Toni Mochty: Bardet Biedl syndrome "avant la lettre". Clin Genet 2019; 97:536-537. [PMID: 31596948 PMCID: PMC7065200 DOI: 10.1111/cge.13647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/16/2019] [Accepted: 09/17/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Wouter de Herder
- Department of Endocrine Oncology, Erasmus MC, Rotterdam, The Netherlands
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Peterson SM, McGill TJ, Puthussery T, Stoddard J, Renner L, Lewis AD, Colgin LMA, Gayet J, Wang X, Prongay K, Cullin C, Dozier BL, Ferguson B, Neuringer M. Bardet-Biedl Syndrome in rhesus macaques: A nonhuman primate model of retinitis pigmentosa. Exp Eye Res 2019; 189:107825. [PMID: 31589838 DOI: 10.1016/j.exer.2019.107825] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 09/27/2019] [Accepted: 09/30/2019] [Indexed: 11/15/2022]
Abstract
The development of therapies for retinal disorders is hampered by a lack of appropriate animal models. Higher nonhuman primates are the only animals with retinal structure similar to humans, including the presence of a macula and fovea. However, few nonhuman primate models of genetic retinal disease are known. We identified a lineage of rhesus macaques with a frameshift mutation in exon 3 of the BBS7 gene c.160delG (p.Ala54fs) that is predicted to produce a non-functional protein. In humans, mutations in this and other BBS genes cause Bardet-Biedl syndrome, a ciliopathy and a syndromic form of retinitis pigmentosa generally occurring in conjunction with kidney dysfunction, polydactyly, obesity, and/or hypogonadism. Three full- or half-sibling monkeys homozygous for the BBS7 c.160delG variant, at ages 3.5, 4 and 6 years old, displayed a combination of severe photoreceptor degeneration and progressive kidney disease. In vivo retinal imaging revealed features of severe macular degeneration, including absence of photoreceptor layers, degeneration of the retinal pigment epithelium, and retinal vasculature atrophy. Electroretinography in the 3.5-year-old case demonstrated loss of scotopic and photopic a-waves and markedly reduced and delayed b-waves. Histological assessments in the 4- and 6-year-old cases confirmed profound loss of photoreceptors and inner retinal neurons across the posterior retina, with dramatic thinning and disorganization of all cell layers, abundant microglia, absent or displaced RPE cells, and significant gliosis in the subretinal space. Retinal structure, including presence of photoreceptors, was preserved only in the far periphery. Ultrasound imaging of the kidneys revealed deranged architecture, and renal histopathology identified distorted contours with depressed, fibrotic foci and firmly adhered renal capsules; renal failure occurred in the 6-year-old case. Magnetic resonance imaging obtained in one case revealed abnormally low total brain volume and unilateral ventricular enlargement. The one male had abnormally small testes at 4 years of age, but polydactyly and obesity were not observed. Thus, monkeys homozygous for the BBS7 c.160delG variant closely mirrored several key features of the human BBS syndrome. This finding represents the first identification of a naturally-occurring nonhuman primate model of BBS, and more broadly the first such model of retinitis pigmentosa and a ciliopathy with an associated genetic mutation. This important new preclinical model will provide the basis for better understanding of disease progression and for the testing of new therapeutic options, including gene and cell-based therapies, not only for BBS but also for multiple forms of photoreceptor degeneration.
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Affiliation(s)
- Samuel M Peterson
- Division of Genetics, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA.
| | - Trevor J McGill
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA; Casey Eye Institute, Oregon Health & Sciences University, Portland, OR, 97239, USA.
| | - Teresa Puthussery
- School of Optometry & Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, 94720, USA.
| | - Jonathan Stoddard
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA.
| | - Lauren Renner
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA.
| | - Anne D Lewis
- Division of Comparative Medicine, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA.
| | - Lois M A Colgin
- Division of Comparative Medicine, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA.
| | - Jacqueline Gayet
- School of Optometry & Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, 94720, USA.
| | - Xiaojie Wang
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA; Advanced Imaging Research Center, Oregon Health & Sciences University, Portland, OR, 97239, USA.
| | - Kamm Prongay
- Division of Comparative Medicine, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA.
| | - Cassandra Cullin
- Division of Comparative Medicine, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA.
| | - Brandy L Dozier
- Division of Comparative Medicine, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA.
| | - Betsy Ferguson
- Division of Genetics, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA; Department of Molecular and Medical Genetics, Oregon Health & Sciences University, Portland, OR, 97239, USA.
| | - Martha Neuringer
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Sciences University, Beaverton, OR, 97006, USA; Casey Eye Institute, Oregon Health & Sciences University, Portland, OR, 97239, USA.
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