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Dobloug S, Kjellström U, Anderson G, Gardner E, Mole SE, Sheth J, Puschmann A. Maculopathy and adult-onset ataxia in patients with biallelic MFSD8 variants. Mol Genet Genomic Med 2024; 12:e2505. [PMID: 39108195 PMCID: PMC11303817 DOI: 10.1002/mgg3.2505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 07/17/2024] [Accepted: 07/24/2024] [Indexed: 08/10/2024] Open
Abstract
BACKGROUND Biallelic variants in the major facilitator superfamily domain containing 8 gene (MFSD8) are associated with distinct clinical presentations that range from typical late-infantile neuronal ceroid lipofuscinosis type 7 (CLN7 disease) to isolated adult-onset retinal dystrophy. Classic late-infantile CLN7 disease is a severe, rare neurological disorder with an age of onset typically between 2 and 6 years, presenting with seizures and/or cognitive regression. Its clinical course is progressive, leading to premature death, and often includes visual loss due to severe retinal dystrophy. In rare cases, pathogenic variants in MFSD8 can be associated with isolated non-syndromic macular dystrophy with variable age at onset, in which the disease process predominantly or exclusively affects the cones of the macula and where there are no neurological or neuropsychiatric manifestations. METHODS Here we present longitudinal studies on four adult-onset patients who were biallelic for four MFSD8 variants. RESULTS Two unrelated patients who presented with adult-onset ataxia and had macular dystrophy on examination were homozygous for a novel variant in MFSD8 NM_152778.4: c.935T>C p.(Ile312Thr). Two other patients presented in adulthood with visual symptoms, and one of these developed mild to moderate cerebellar ataxia years after the onset of visual symptoms. CONCLUSIONS Our observations expand the knowledge on biallelic pathogenic MFSD8 variants and confirm that these are associated with a spectrum of more heterogeneous clinical phenotypes. In MFSD8-related disease, adult-onset recessive ataxia can be the presenting manifestation or may occur in combination with retinal dystrophy.
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Affiliation(s)
- Sigurd Dobloug
- Department of NeurologyHelsingborg General HospitalHelsingborgSweden
- Department for Clinical Sciences, Lund, NeurologyLund UniversityLundSweden
| | | | - Glenn Anderson
- Department of HistopathologyGreat Ormond Street HospitalLondonUK
| | - Emily Gardner
- Great Ormond Street Institute of Child HealthUniversity College LondonLondonUK
| | - Sara E. Mole
- Great Ormond Street Institute of Child HealthUniversity College LondonLondonUK
| | - Jayesh Sheth
- Foundation for Research in Genetics and EndocrinologyInstitute of Human GeneticsAhmedabadIndia
| | - Andreas Puschmann
- Lund University, Skåne University Hospital, NeurologyLundSweden
- SciLifeLabLund UniversityLundSweden
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2
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Kayani S, Edgar VB, Lowden A, Nettesheim ER, Dahshi H, Messahel S, Minassian BA, Greenberg BM. Neuronal Ceroid Lipofuscinoses Type 7 (CLN7)- A Case Series Reporting Cross Sectional and Retrospective Clinical Data to Evaluate Validity of Standardized Tools to Assess Disease Progression, Quality of Life, and Adaptive Skills. RESEARCH SQUARE 2024:rs.3.rs-3983366. [PMID: 38978590 PMCID: PMC11230482 DOI: 10.21203/rs.3.rs-3983366/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Background This study evaluated the clinical characteristics of neuronal ceroid lipofuscinosis type 7 or CLN7 disease spectrum to characterize the clinical, electrophysiologic and neuroimaging phenotypes. Methods We performed a single-center cross sectional data collection along with retrospective medical chart review in patients with a genetic diagnosis of CLN7. This study received ethical approval by the University of Texas Southwestern Medical Center Institutional Review Board. A total of 8 patients were included between the ages of 4 to 6 years. All patients had a genetic diagnosis of CLN7 with homozygous or compound heterozygous mutations in the MFSD8 gene. The information collected includes patient demographics, developmental history, neurological events including seizures and neurodevelopmental regression along with further evaluation of brain magnetic resonance imaging and electrophysiological findings. The clinical phenotype is described through cross sectional and retrospective data collection and standardized tools assessing quality of life and functional skills. Conclusions Our findings in this cohort of CLN7 patients indicated that development is initially normal with onset of clinical symptoms as early as two years of age. Language problems were noted prior to or at the onset of seizures in all cases. Gait problems were noted prior to seizure onset in 3 of 8 patients, and at or within 6 months after the onset of seizures in 5 of 8 patients. All patients followed a progressive course of language, motor, and neurocognitive deterioration. Congruent with the medical history, our patients had significantly low scores on adaptive abilities. Natural history data such as this can be used to support future clinical trial designs.
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Affiliation(s)
- Saima Kayani
- UT Southwestern: The University of Texas Southwestern Medical Center
| | | | - Andrea Lowden
- UT Southwestern: The University of Texas Southwestern Medical Center
| | | | - Hamza Dahshi
- UT Southwestern: The University of Texas Southwestern Medical Center
| | - Souad Messahel
- UT Southwestern: The University of Texas Southwestern Medical Center
| | - Berge A Minassian
- UT Southwestern: The University of Texas Southwestern Medical Center
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Linear Diagnostic Procedure Elicited by Clinical Genetics and Validated by mRNA Analysis in Neuronal Ceroid Lipofuscinosis 7 Associated with a Novel Non-Canonical Splice Site Variant in MFSD8. Genes (Basel) 2023; 14:genes14020245. [PMID: 36833170 PMCID: PMC9956376 DOI: 10.3390/genes14020245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/08/2023] [Accepted: 01/16/2023] [Indexed: 01/19/2023] Open
Abstract
Neuronal ceroid lipofuscinoses (CNL) are lysosomal storage diseases that represent the most common cause of dementia in children. To date, 13 autosomal recessive (AR) and 1 autosomal dominant (AD) gene have been characterized. Biallelic variants in MFSD8 cause CLN7 type, with nearly 50 pathogenic variants, mainly truncating and missense, reported so far. Splice site variants require functional validation. We detected a novel homozygous non-canonical splice-site variant in MFSD8 in a 5-year-old girl who presented with progressive neurocognitive impairment and microcephaly. The diagnostic procedure was elicited by clinical genetics first, and then confirmed by cDNA sequencing and brain imaging. Inferred by the common geographic origin of the parents, an autosomal recessive inheritance was hypothesized, and SNP-array was performed as the first-line genetic test. Only three AR genes lying within the observed 24 Mb regions of homozygosity were consistent with the clinical phenotype, including EXOSC9, SPATA5 and MFSD8. The cerebral and cerebellar atrophy detected in the meantime by MRI, along with the suspicion of accumulation of ceroid lipopigment in neurons, prompted us to perform targeted MFSD8 sequencing. Following the detection of a splice site variant of uncertain significance, skipping of exon 8 was demonstrated by cDNA sequencing, and the variant was redefined as pathogenic.
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Lange LM, Gonzalez-Latapi P, Rajalingam R, Tijssen MAJ, Ebrahimi-Fakhari D, Gabbert C, Ganos C, Ghosh R, Kumar KR, Lang AE, Rossi M, van der Veen S, van de Warrenburg B, Warner T, Lohmann K, Klein C, Marras C. Nomenclature of Genetic Movement Disorders: Recommendations of the International Parkinson and Movement Disorder Society Task Force - An Update. Mov Disord 2022; 37:905-935. [PMID: 35481685 DOI: 10.1002/mds.28982] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/28/2022] [Accepted: 02/14/2022] [Indexed: 12/13/2022] Open
Abstract
In 2016, the Movement Disorder Society Task Force for the Nomenclature of Genetic Movement Disorders presented a new system for naming genetically determined movement disorders and provided a criterion-based list of confirmed monogenic movement disorders. Since then, a substantial number of novel disease-causing genes have been described, which warrant classification using this system. In addition, with this update, we further refined the system and propose dissolving the imaging-based categories of Primary Familial Brain Calcification and Neurodegeneration with Brain Iron Accumulation and reclassifying these genetic conditions according to their predominant phenotype. We also introduce the novel category of Mixed Movement Disorders (MxMD), which includes conditions linked to multiple equally prominent movement disorder phenotypes. In this article, we present updated lists of newly confirmed monogenic causes of movement disorders. We found a total of 89 different newly identified genes that warrant a prefix based on our criteria; 6 genes for parkinsonism, 21 for dystonia, 38 for dominant and recessive ataxia, 5 for chorea, 7 for myoclonus, 13 for spastic paraplegia, 3 for paroxysmal movement disorders, and 6 for mixed movement disorder phenotypes; 10 genes were linked to combined phenotypes and have been assigned two new prefixes. The updated lists represent a resource for clinicians and researchers alike and they have also been published on the website of the Task Force for the Nomenclature of Genetic Movement Disorders on the homepage of the International Parkinson and Movement Disorder Society (https://www.movementdisorders.org/MDS/About/Committees--Other-Groups/MDS-Task-Forces/Task-Force-on-Nomenclature-in-Movement-Disorders.htm). © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson Movement Disorder Society.
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Affiliation(s)
- Lara M Lange
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Paulina Gonzalez-Latapi
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada.,Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Rajasumi Rajalingam
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
| | - Marina A J Tijssen
- UMCG Expertise Centre Movement Disorders, Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Darius Ebrahimi-Fakhari
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.,The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, Massachusetts, USA
| | - Carolin Gabbert
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Christos Ganos
- Department of Neurology, Charité University Hospital Berlin, Berlin, Germany
| | - Rhia Ghosh
- Huntington's Disease Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Kishore R Kumar
- Molecular Medicine Laboratory and Department of Neurology, Concord Repatriation General Hospital, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia.,Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Anthony E Lang
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
| | - Malco Rossi
- Movement Disorders Section, Neuroscience Department, Raul Carrea Institute for Neurological Research (FLENI), Buenos Aires, Argentina
| | - Sterre van der Veen
- UMCG Expertise Centre Movement Disorders, Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Bart van de Warrenburg
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Center of Expertise for Parkinson and Movement Disorders, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Tom Warner
- Department of Clinical & Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Katja Lohmann
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Christine Klein
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Connie Marras
- The Edmond J. Safra Program in Parkinson's Disease and The Morton and Gloria Shulman Movement Disorder Clinic, Toronto Western Hospital, University of Toronto, Toronto, Canada
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A Novel, Apparently Silent Variant in MFSD8 Causes Neuronal Ceroid Lipofuscinosis with Marked Intrafamilial Variability. Int J Mol Sci 2022; 23:ijms23042271. [PMID: 35216386 PMCID: PMC8877174 DOI: 10.3390/ijms23042271] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/09/2022] [Accepted: 02/16/2022] [Indexed: 02/06/2023] Open
Abstract
Variants in MFSD8 can cause neuronal ceroid lipofuscinoses (NCLs) as well as nonsyndromic retinopathy. The mutation spectrum includes mainly missense and stop variants, but splice sites and frameshift variants have also been reported. To date, apparently synonymous substitutions have not been shown to cause MFSD8-associated diseases. We report two closely related subjects from a consanguineous Turkish family who presented classical features of NCLs but demonstrated marked intrafamilial variability in age at the onset and severity of symptoms. In fact, the difference in the onset of first neurologic symptoms was 15 years and that of ophthalmologic symptoms was 12 years. One subject presented an intellectual disability and a considerable cerebellar ataxia syndrome, while the other subject showed no intellectual disability and only a mild atactic syndrome. The diagnostic genetic testing of both subjects based on genome sequencing prioritized a novel, apparently synonymous variant in MFSD8, which was found in homozygosity in both subjects. The variant was not located within an integral part of the splice site consensus sequences. However, the bioinformatic analyses suggested that the mutant allele is more likely to cause exon skipping due to an altered ratio of exonic splice enhancer and silencer motifs. Exon skipping was confirmed in vitro by minigene assays and in vivo by RNA analysis from patient lymphocytes. The mutant transcript is predicted to result in a frameshift and, if translated, in a truncated protein. Synonymous variants are often given a low priority in genetic diagnostics because of their expected lack of functional impact. This study highlights the importance of investigating the impact of synonymous variants on splicing.
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Spagnoli C, Fusco C, Pisani F. Rett Syndrome Spectrum in Monogenic Developmental-Epileptic Encephalopathies and Epilepsies: A Review. Genes (Basel) 2021; 12:genes12081157. [PMID: 34440332 PMCID: PMC8394997 DOI: 10.3390/genes12081157] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/21/2021] [Accepted: 07/23/2021] [Indexed: 01/22/2023] Open
Abstract
INTRODUCTION Progress in the clinical application of next-generation-sequencing-based techniques has resulted in a dramatic increase in the recognized genetic heterogeneity of the Rett syndrome spectrum (RSS). Our awareness of the considerable overlap with pediatric-onset epilepsies and epileptic/developmental encephalopathies (EE/DE) genes is also growing, and the presence of variable clinical features inside a general frame of commonalities has drawn renewed attention into deep phenotyping. METHODS We decided to review the medical literature on atypical Rett syndrome and "Rett-like" phenotypes, with special emphasis on described cases with pediatric-onset epilepsies and/or EE-DE, evaluating Neul's criteria for Rett syndrome and associated movement disorders and notable stereotypies. RESULTS "Rett-like" features were described in syndromic and non-syndromic monogenic epilepsy- and DE/EE-related genes, in "intellectual disability plus epilepsy"-related genes and in neurodegenerative disorders. Additionally, prominent stereotypies can be observed in monogenic complex neurodevelopmental disorders featuring epilepsy with or without autistic features outside of the RSS. CONCLUSIONS Patients share a complex neurodevelopmental and neurological phenotype (developmental delay, movement disorder) with impaired gait, abnormal tone and hand stereotypies. However, the presence and characteristics of regression and loss of language and functional hand use can differ. Finally, the frequency of additional supportive criteria and their distribution also vary widely.
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Affiliation(s)
- Carlotta Spagnoli
- Child Neurology Unit, AUSL-IRCCS di Reggio Emilia, 42123 Reggio Emilia, Italy;
- Correspondence:
| | - Carlo Fusco
- Child Neurology Unit, AUSL-IRCCS di Reggio Emilia, 42123 Reggio Emilia, Italy;
| | - Francesco Pisani
- Child Neuropsychiatry Unit, University-Hospital of Parma, 43123 Parma, Italy;
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7
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Singanamalla B, Madaan P, Saini L, Sankhyan N. Child with predominant midline stereotypies and infrequent seizures. BMJ Case Rep 2021; 14:e238764. [PMID: 33472805 PMCID: PMC10577734 DOI: 10.1136/bcr-2020-238764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/30/2020] [Indexed: 11/16/2022] Open
Affiliation(s)
- Bhanudeep Singanamalla
- Pediatric Neurology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Priyanka Madaan
- Pediatric Neurology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
- Pediatrics, Council of Scientific and Industrial Research, CSIR complex, Library Avenue, Pusa, New Delhi, India
| | - Lokesh Saini
- Pediatric Neurology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Naveen Sankhyan
- Pediatric Neurology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
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8
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Kozina AA, Okuneva EG, Baryshnikova NV, Kondakova OB, Nikolaeva EA, Fedoniuk ID, Mikhailova SV, Krasnenko AY, Stetsenko IF, Plotnikov NA, Klimchuk OI, Popov YV, Surkova EI, Shatalov PA, Rakitko AS, Ilinsky VV. Neuronal ceroid lipofuscinosis in the Russian population: Two novel mutations and the prevalence of heterozygous carriers. Mol Genet Genomic Med 2020; 8:e1228. [PMID: 32412666 PMCID: PMC7336735 DOI: 10.1002/mgg3.1228] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 02/28/2020] [Accepted: 03/09/2020] [Indexed: 12/30/2022] Open
Abstract
Background Neuronal ceroid lipofuscinoses (NCLs) are a group of neurodegenerative disorders characterized by an accumulation of lipofuscin in the body's tissues. NCLs are associated with variable age of onset and progressive symptoms including seizures, psychomotor decline, and loss of vision. Methods We describe the clinical and molecular characteristics of four Russian patients with NCL (one female and three males, with ages ranging from 4 to 5 years). The clinical features of these patients include cognitive and motor deterioration, seizures, stereotypies, and magnetic resonance imaging signs of brain atrophy. Exome sequencing was performed to identify the genetic variants of patients with NCL. Additionally, we tested 6,396 healthy Russians for NCL alleles. Results We identified five distinct mutations in four NCL‐associated genes of which two mutations are novel. These include a novel homozygous frameshift mutation in the CLN6 gene, a compound heterozygous missense mutation in the KCTD7 gene, and previously known mutations in KCTD7, TPP1, and MFSD8 genes. Furthermore, we estimated the Russian population carrier frequency of pathogenic and likely pathogenic variants in 13 genes associated with different types of NCL. Conclusion Our study expands the spectrum of mutations in lipofuscinosis. This is the first study to describe the molecular basis of NCLs in Russia and has profound and numerous clinical implications for diagnosis, genetic counseling, genotype–phenotype correlations, and prognosis.
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Affiliation(s)
- Anastasiya A Kozina
- Institute of Biomedical Chemistry, Moscow, Russia.,Pirogov Russian National Research Medical University, Moscow, Russia
| | | | - Natalia V Baryshnikova
- Pirogov Russian National Research Medical University, Moscow, Russia.,Genotek Ltd., Moscow, Russia
| | - Olga B Kondakova
- Scientific and Practical Centre of Pediatric Psychoneurology of Moscow Healthcare Department, Moscow, Russia
| | - Ekaterina A Nikolaeva
- Veltischev Research and Clinical Institute for Pediatrics of the Pirogov Russian National Research Medical University, Moscow, Russia
| | | | | | | | | | | | | | | | | | - Peter A Shatalov
- Genotek Ltd., Moscow, Russia.,Veltischev Research and Clinical Institute for Pediatrics of the Pirogov Russian National Research Medical University, Moscow, Russia
| | - Alexander S Rakitko
- Genotek Ltd., Moscow, Russia.,Faculty of Mechanics and Mathematics, Lomonosov Moscow State University, Moscow, Russia
| | - Valery V Ilinsky
- Institute of Biomedical Chemistry, Moscow, Russia.,Pirogov Russian National Research Medical University, Moscow, Russia.,Genotek Ltd., Moscow, Russia.,Vavilov Institute of General Genetics, Moscow, Russia
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Zare-Abdollahi D, Bushehri A, Alavi A, Dehghani A, Mousavi-Mirkala M, Effati J, Miratashi SAM, Dehani M, Jamali P, Khorram Khorshid HR. MFSD8 gene mutations; evidence for phenotypic heterogeneity. Ophthalmic Genet 2019; 40:141-145. [PMID: 31006324 DOI: 10.1080/13816810.2019.1592200] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Cone-rod dystrophies are a group of genetically and phenotypically heterogeneous inherited degenerative retinal diseases primarily affecting macular and cone system function. MFSD8 loss-of-function variants are mainly related to the variant late-infantile neuronal ceroid lipofuscinoses which present with progressive motor and mental regression in combination with seizures, ataxia, and visual impairment. MATERIAL AND METHODS Clinical examination and genomic DNA extraction were collected from two unrelated Iranian families presenting with autosomal recessive cone-rod dystrophy. The candidate disease-causing variant was screened with whole-exome sequencing and bioinformatics analyses. Sanger sequencing was used for validation and co-segregation analysis. RESULTS Two previously reported variants (c.1361T>C; p.M454T and c.1235C>T; p.P412L) and in a compound heterozygous pattern in one family and a homozygous variant (c.1361T>C; p.M454T) identical to one of the variants in the first family in MFSD8 gene were identified. Both confirmed by Sanger sequencing and co-segregated with disease status. CONCLUSIONS Here and for the first time, we reported on two previously variant late-infantile neuronal ceroid lipofuscinoses-associated variants in MFSD8 but in association with a form of cone-rod dystrophy known as non-syndromic macular dystrophy with central cone involvement. Our results support this concept that variant late-infantile neuronal ceroid lipofuscinoses and non-syndromic macular dystrophy with central cone involvement are not different disease entities, but rather allelic diseases and phenotypic variants of the same mutation. Consideration of the milder MFSD8 phenotypes is important against the potentially severe consequences of life-threatening conditions associated with MFSD8 mutations in order to prevent the danger of misdiagnosis as well as the accuracy of genetic counseling.
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Affiliation(s)
- Davood Zare-Abdollahi
- a Genetics Research Center , University of Social Welfare and Rehabilitation Sciences , Tehran , Iran
| | - Ata Bushehri
- a Genetics Research Center , University of Social Welfare and Rehabilitation Sciences , Tehran , Iran
| | - Afagh Alavi
- a Genetics Research Center , University of Social Welfare and Rehabilitation Sciences , Tehran , Iran
| | - Alireza Dehghani
- b Department of Ophthalmology , Eye Research Center, Isfahan University of Medical Sciences , Isfahan , Iran
| | | | - Jalil Effati
- d Meybod Genetic Research Center, State Welfare Organization of Yazd , Yazd , Iran
| | | | - Mohammad Dehani
- a Genetics Research Center , University of Social Welfare and Rehabilitation Sciences , Tehran , Iran
| | - Payman Jamali
- f Shahrood Genetic Counseling Center , Welfare Office , Semnan , Iran
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