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Öztürk Ö, Bagis H, Bolu S. Osteogenesis Imperfecta and Split Foot Malformation due to 7q21.2q21.3 Deletion Including COL1A2, DLX5/6 Genes: Review of the Literature. J Pediatr Genet 2024; 13:69-79. [PMID: 38567169 PMCID: PMC10984717 DOI: 10.1055/s-0041-1736613] [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: 04/11/2021] [Accepted: 09/22/2021] [Indexed: 10/19/2022]
Abstract
Copy number variation in loss of 7q21 is a genetic disorder characterized by split hand/foot malformation, hearing loss, developmental delay, myoclonus, dystonia, joint laxity, and psychiatric disorders. Osteogenesis imperfecta caused by whole gene deletions of COL1A2 is a very rare condition. We report a Turkish girl with ectrodactyly, joint laxity, multiple bone fractures, blue sclera, early teeth decay, mild learning disability, and depression. A copy number variant in loss of 4.8 Mb at chromosome 7 (q21.2q21.3) included the 58 genes including DLX5, DLX6, DYNC1I1, SLC25A13, SGCE, and COL1A2 . They were identified by chromosomal microarray analysis. We compared the findings in our patients with those previously reported. This case report highlights the importance of using microarray to identify the genetic etiology in patients with ectrodactyly and osteogenesis imperfecta.
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Affiliation(s)
- Özden Öztürk
- Department of Medical Genetics, Medical School of Adiyaman University, Adiyaman, Türkiye
| | - Haydar Bagis
- Department of Medical Genetics, Medical School of Adiyaman University, Adiyaman, Türkiye
| | - Semih Bolu
- Department of Pediatrics, Division of Pediatric Endocrinology, Medical School of Adiyaman University, Adiyaman, Türkiye
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2
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Menozzi E, Balint B, Latorre A, Valente EM, Rothwell JC, Bhatia KP. Twenty years on: Myoclonus-dystonia and ε-sarcoglycan - neurodevelopment, channel, and signaling dysfunction. Mov Disord 2019; 34:1588-1601. [PMID: 31449710 DOI: 10.1002/mds.27822] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 06/19/2019] [Accepted: 07/14/2019] [Indexed: 12/26/2022] Open
Abstract
Myoclonus-dystonia is a clinical syndrome characterized by a typical childhood onset of myoclonic jerks and dystonia involving the neck, trunk, and upper limbs. Psychiatric symptomatology, namely, alcohol dependence and phobic and obsessive-compulsive disorder, is also part of the clinical picture. Zonisamide has demonstrated effectiveness at reducing both myoclonus and dystonia, and deep brain stimulation seems to be an effective and long-lasting therapeutic option for medication-refractory cases. In a subset of patients, myoclonus-dystonia is associated with pathogenic variants in the epsilon-sarcoglycan gene, located on chromosome 7q21, and up to now, more than 100 different pathogenic variants of the epsilon-sarcoglycan gene have been described. In a few families with a clinical phenotype resembling myoclonus-dystonia associated with distinct clinical features, variants have been identified in genes involved in novel pathways such as calcium channel regulation and neurodevelopment. Because of phenotypic similarities with epsilon-sarcoglycan gene-related myoclonus-dystonia, these conditions can be collectively classified as "myoclonus-dystonia syndromes." In the present article, we present myoclonus-dystonia caused by epsilon-sarcoglycan gene mutations, with a focus on genetics and underlying disease mechanisms. Second, we review those conditions falling within the spectrum of myoclonus-dystonia syndromes, highlighting their genetic background and involved pathways. Finally, we critically discuss the normal and pathological function of the epsilon-sarcoglycan gene and its product, suggesting a role in the stabilization of the dopaminergic membrane via regulation of calcium homeostasis and in the neurodevelopmental process involving the cerebello-thalamo-pallido-cortical network. © 2019 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Elisa Menozzi
- Department of Biomedical, Metabolic and Neural Sciences, University-Hospital of Modena and Reggio Emilia, Modena, Italy.,Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
| | - Bettina Balint
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK.,Department of Neurology, University Hospital Heidelberg, Heidelberg, Germany
| | - Anna Latorre
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK.,Department of Human Neurosciences, Sapienza University of Rome, Rome, Italy
| | - Enza Maria Valente
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Neurogenetics Unit, IRCCS Santa Lucia Foundation, Rome, Italy
| | - John C Rothwell
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
| | - Kailash P Bhatia
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
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3
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Peall KJ, Dijk JM, Saunders-Pullman R, Dreissen YEM, van Loon I, Cath D, Kurian MA, Owen MJ, Foncke EMJ, Morris HR, Gasser T, Bressman S, Asmus F, Tijssen MAJ. Psychiatric disorders, myoclonus dystonia and SGCE: an international study. Ann Clin Transl Neurol 2015; 3:4-11. [PMID: 26783545 PMCID: PMC4704478 DOI: 10.1002/acn3.263] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 09/25/2015] [Indexed: 01/22/2023] Open
Abstract
Objective Myoclonus‐dystonia (M‐D) is a hyperkinetic movement disorder, typically alcohol‐responsive upper body myoclonus and dystonia. The majority of autosomal dominant familial cases are caused by epsilon‐sarcoglycan gene (SGCE) mutations. Previous publications have observed increased rates of psychiatric disorders amongst SGCE mutation‐positive populations. We analyzed the psychiatric data from four international centers, forming the largest cohort to date, to further determine the extent and type of psychiatric disorders in M‐D. Methods Psychiatric data from SGCE mutation‐positive M‐D cohorts, collected by movement disorder specialists in the Netherlands, United Kingdom, United States, and Germany, were analyzed. These data were collected using standardized, systematic questionnaires allowing classification of symptoms according to Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM‐IV) criteria. Based on motor findings and SGCE mutation analysis, participants were classified into one of three groups: manifesting carriers, nonmanifesting carriers and noncarriers. Results Data from 307 participants were evaluated (140 males, 167 females, mean age at examination: 42.5 years). Two‐thirds of motor affected mutation carriers (n = 132) had ≥1 psychiatric diagnosis, specific, and social phobias being most common followed by alcohol dependence and obsessive‐compulsive disorder (OCD). Compared to familial controls, affected mutation carriers had significantly elevated overall rates of psychiatric disorders (P < 0.001). The most significant differences were observed with alcohol dependence (P < 0.001), OCD (P < 0.001), social and specific phobias (P < 0.001). Interpretation M‐D due to SGCE mutations is associated with specific psychiatric disorders, most commonly OCD, anxiety‐related disorders, and alcohol dependence. These suggest either a potential pleiotropic function for SGCE within the central nervous system or a secondary effect of the motor disorder.
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Affiliation(s)
- Kathryn J Peall
- Department of Neurology University Medical Center Groningen Groningen The Netherlands; Institute of Psychological Medicine and Clinical Neurosciences MRC Centre for Neuropsychiatric Genetics and Genomics Cardiff University Cardiff United Kingdom
| | - Joke M Dijk
- Department of Neurology The Academic Medical Center Amsterdam The Netherlands
| | | | | | - Ilke van Loon
- Department of Neurology The Academic Medical Center Amsterdam The Netherlands
| | - Danielle Cath
- Department of Behavioural Sciences - Clinical and Health Psychology University of Utrecht Utrecht The Netherlands
| | - Manju A Kurian
- Institute of Child Health - Neurosciences Unit University College London London United Kingdom; Department of Neurology Great Ormond Street Hospital London United Kingdom
| | - Michael J Owen
- Institute of Psychological Medicine and Clinical Neurosciences MRC Centre for Neuropsychiatric Genetics and Genomics Cardiff University Cardiff United Kingdom
| | | | - Huw R Morris
- Institute of Psychological Medicine and Clinical Neurosciences MRC Centre for Neuropsychiatric Genetics and Genomics Cardiff University Cardiff United Kingdom
| | - Thomas Gasser
- Department for Neurodegenerative Diseases Hertie Institute for Clinical Brain Research Tubingen Germany
| | - Susan Bressman
- The Saul R. Korey Department of Neurology Beth Israel Medical Centre New York
| | - Friedrich Asmus
- Department for Neurodegenerative Diseases Hertie Institute for Clinical Brain Research Tubingen Germany
| | - Marina A J Tijssen
- Department of Neurology University Medical Center Groningen Groningen The Netherlands
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4
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Peall KJ, Kurian MA, Wardle M, Waite AJ, Hedderly T, Lin JP, Smith M, Whone A, Pall H, White C, Lux A, Jardine PE, Lynch B, Kirov G, O'Riordan S, Samuel M, Lynch T, King MD, Chinnery PF, Warner TT, Blake DJ, Owen MJ, Morris HR. SGCE and myoclonus dystonia: motor characteristics, diagnostic criteria and clinical predictors of genotype. J Neurol 2014; 261:2296-304. [PMID: 25209853 PMCID: PMC4495322 DOI: 10.1007/s00415-014-7488-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 08/29/2014] [Accepted: 08/31/2014] [Indexed: 10/24/2022]
Abstract
Myoclonus dystonia syndrome (MDS) is a young-onset movement disorder. A proportion of cases are due to mutations in the maternally imprinted SGCE gene. We assembled the largest cohort of MDS patients to date, and determined the frequency and type of SGCE mutations. The aim was to establish the motor phenotype in mutation carriers and utility of current diagnostic criteria. Eighty-nine probands with clinical features compatible with MDS were recruited from the UK and Ireland. Patients were phenotypically classified as "definite", "probable" or "possible" MDS according to previous guidelines. SGCE was analyzed using direct sequencing and copy number variant analysis. In those where no mutation was found, DYT1 (GAG deletion), GCH1, THAP1 and NKX2.1 genes were also sequenced. Nineteen (21.3%) probands had an SGCE mutation. Three patterns of motor symptoms emerged: (1) early childhood onset upper body myoclonus and dystonia, (2) early childhood onset lower limb dystonia, progressing later to more pronounced myoclonus and upper body involvement, and (3) later childhood onset upper body myoclonus and dystonia with evident cervical involvement. Five probands had large contiguous gene deletions ranging from 0.7 to 2.3 Mb in size with distinctive clinical features, including short stature, joint laxity and microcephaly. Our data confirms that SGCE mutations are most commonly identified in MDS patients with (1) age at onset ≤10 years and (2) predominant upper body involvement of a pure myoclonus-dystonia. Cases with whole SGCE gene deletions had additional clinical characteristics, which are not always predicted by deletion size or gene involvement.
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Affiliation(s)
- Kathryn J Peall
- MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, School of Medicine, Cardiff University, Hadyn Ellis Building, Maindy Road, Cardiff, CF24 4HQ, UK,
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Carecchio M, Magliozzi M, Copetti M, Ferraris A, Bernardini L, Bonetti M, Defazio G, Edwards MJ, Torrente I, Pellegrini F, Comi C, Bhatia KP, Valente EM. Defining the Epsilon-Sarcoglycan (SGCE) Gene Phenotypic Signature in Myoclonus-Dystonia: A Reappraisal of Genetic Testing Criteria. Mov Disord 2013; 28:787-94. [DOI: 10.1002/mds.25506] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 03/27/2013] [Accepted: 04/09/2013] [Indexed: 11/11/2022] Open
Affiliation(s)
- Miryam Carecchio
- Sobell Department of Motor Neuroscience and Movement Disorders; UCL Institute of Neurology; London United Kingdom
- Department of Neurology; Amedeo Avogadro University; Novara Italy
| | - Monia Magliozzi
- CSS-Mendel Laboratory; IRCCS Casa Sollievo della Sofferenza; San Giovanni Rotondo Italy
| | - Massimiliano Copetti
- Biostatistics Unit; IRCCS Casa Sollievo della Sofferenza; San Giovanni Rotondo Italy
| | - Alessandro Ferraris
- CSS-Mendel Laboratory; IRCCS Casa Sollievo della Sofferenza; San Giovanni Rotondo Italy
| | - Laura Bernardini
- CSS-Mendel Laboratory; IRCCS Casa Sollievo della Sofferenza; San Giovanni Rotondo Italy
| | - Monica Bonetti
- CSS-Mendel Laboratory; IRCCS Casa Sollievo della Sofferenza; San Giovanni Rotondo Italy
| | - Giovanni Defazio
- Department of Neurosciences and Sensory Organs; School of Motor Sciences; “Aldo Moro” University of Bari; Bari Italy
| | - Mark J. Edwards
- Sobell Department of Motor Neuroscience and Movement Disorders; UCL Institute of Neurology; London United Kingdom
| | - Isabella Torrente
- CSS-Mendel Laboratory; IRCCS Casa Sollievo della Sofferenza; San Giovanni Rotondo Italy
| | - Fabio Pellegrini
- Biostatistics Unit; IRCCS Casa Sollievo della Sofferenza; San Giovanni Rotondo Italy
- Laboratory of Clinical Epidemiology of Diabetes and Chronic Diseases; Consorzio Mario Negri Sud; Santa Maria Imbaro Italy
| | - Cristoforo Comi
- Department of Neurology; Amedeo Avogadro University; Novara Italy
| | - Kailash P. Bhatia
- Sobell Department of Motor Neuroscience and Movement Disorders; UCL Institute of Neurology; London United Kingdom
| | - Enza Maria Valente
- CSS-Mendel Laboratory; IRCCS Casa Sollievo della Sofferenza; San Giovanni Rotondo Italy
- Department of Medicine and Surgery; University of Salerno; Salerno Italy
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Peall KJ, Smith DJ, Kurian MA, Wardle M, Waite AJ, Hedderly T, Lin JP, Smith M, Whone A, Pall H, White C, Lux A, Jardine P, Bajaj N, Lynch B, Kirov G, O'Riordan S, Samuel M, Lynch T, King MD, Chinnery PF, Warner TT, Blake DJ, Owen MJ, Morris HR. SGCE mutations cause psychiatric disorders: clinical and genetic characterization. ACTA ACUST UNITED AC 2013; 136:294-303. [PMID: 23365103 DOI: 10.1093/brain/aws308] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Myoclonus dystonia syndrome is a childhood onset hyperkinetic movement disorder characterized by predominant alcohol responsive upper body myoclonus and dystonia. A proportion of cases are due to mutations in the maternally imprinted SGCE gene. Previous studies have suggested that patients with SGCE mutations may have an increased rate of psychiatric disorders. We established a cohort of patients with myoclonus dystonia syndrome and SGCE mutations to determine the extent to which psychiatric disorders form part of the disease phenotype. In all, 89 patients with clinically suspected myoclonus dystonia syndrome were recruited from the UK and Ireland. SGCE was analysed using direct sequencing and for copy number variants. In those patients where no mutation was found TOR1A (GAG deletion), GCH1, THAP1 and NKX2-1 were also sequenced. SGCE mutation positive cases were systematically assessed using standardized psychiatric interviews and questionnaires and compared with a disability-matched control group of patients with alcohol responsive tremor. Nineteen (21%) probands had a SGCE mutation, five of which were novel. Recruitment of family members increased the affected SGCE mutation positive group to 27 of whom 21 (77%) had psychiatric symptoms. Obsessive-compulsive disorder was eight times more likely (P < 0.001) in mutation positive cases, compulsivity being the predominant feature (P < 0.001). Generalized anxiety disorder (P = 0.003) and alcohol dependence (P = 0.02) were five times more likely in mutation positive cases than tremor controls. SGCE mutations are associated with a specific psychiatric phenotype consisting of compulsivity, anxiety and alcoholism in addition to the characteristic motor phenotype. SGCE mutations are likely to have a pleiotropic effect in causing both motor and specific psychiatric symptoms.
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Affiliation(s)
- Kathryn J Peall
- MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Henry Wellcome Building, Heath Park, Cardiff, UK.
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7
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Xiao J, Nance MA, LeDoux MS. Incomplete nonsense-mediated decay facilitates detection of a multi-exonic deletion mutation in SGCE. Clin Genet 2012; 84:276-80. [PMID: 23140253 DOI: 10.1111/cge.12059] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Revised: 11/06/2012] [Accepted: 11/06/2012] [Indexed: 11/26/2022]
Abstract
Mutations in SGCE represent the major cause of the myoclonus-dystonia syndrome (DYT11), an autosomal dominant disorder of reduced penetrance. Virtually all affected individuals have myoclonus, which is concentrated in the upper extremities, neck and trunk. Over half of patients have dystonia, usually affecting the neck or arms. SGCE is maternally imprinted. Of the more than 70 SGCE mutations reported in the literature, 18 are large deletions disrupting at least one exon. Therefore, testing for exonic deletions should be considered in individuals with a classic phenotype in whom Sanger sequencing is unrevealing. However, standard methodologies for detection of exonic deletion mutations are expensive, labor intensive and can produce false negatives. Herein, we report the use of cDNA derived from leukocyte RNA to identify a deletion mutation (exons 4 and 5) of SGCE in a family with DYT11. Residual RNA from incomplete nonsense-mediated decay permitted reverse transcription to cDNA. Breakpoints of the 8939 bp heterozygous deletion were then defined with long-range polymerase chain reaction and Sanger sequencing. Use of cDNA generated by reverse transcription of leukocyte RNA can reduce the costs associated with diagnostic genetic testing and can facilitate detection of deletion mutations.
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Affiliation(s)
- J Xiao
- Department of Neurology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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Birnbaum RY, Everman DB, Murphy KK, Gurrieri F, Schwartz CE, Ahituv N. Functional characterization of tissue-specific enhancers in the DLX5/6 locus. Hum Mol Genet 2012; 21:4930-8. [PMID: 22914741 DOI: 10.1093/hmg/dds336] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Disruption of distaless homeobox 5 and 6 (Dlx5/6) in mice results in brain, craniofacial, genital, ear and limb defects. In humans, chromosomal aberrations in the DLX5/6 region, some of which do not encompass DLX5/6, are associated with split hand/foot malformation 1 (SHFM1) as well as intellectual disability, craniofacial anomalies and hearing loss, suggesting that the disruption of DLX5/6 regulatory elements could lead to these abnormalities. Here, we characterized enhancers in the DLX5/6 locus whose tissue-specific expression and genomic location along with previously characterized enhancers correlate with phenotypes observed in individuals with chromosomal abnormalities. By analyzing chromosomal aberrations at 7q21, we refined the minimal SHFM1 critical region and used comparative genomics to select 26 evolutionary conserved non-coding sequences in this critical region for zebrafish enhancer assays. Eight of these sequences were shown to function as brain, olfactory bulb, branchial arch, otic vesicle and fin enhancers, recapitulating dlx5a/6a expression. Using a mouse enhancer assay, several of these zebrafish enhancers showed comparable expression patterns in the branchial arch, otic vesicle, forebrain and/or limb at embryonic day 11.5. Examination of the coordinates of various chromosomal rearrangements in conjunction with the genomic location of these tissue-specific enhancers showed a correlation with the observed clinical abnormalities. Our findings suggest that chromosomal abnormalities that disrupt the function of these tissue-specific enhancers could be the cause of SHFM1 and its associated phenotypes. In addition, they highlight specific enhancers in which mutations could lead to non-syndromic hearing loss, craniofacial defects or limb malformations.
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Affiliation(s)
- Ramon Y Birnbaum
- Department of Bioengineering and Therapeutic Sciences and 2Institute for Human Genetics, University of California-San Francisco, CA, USA
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Abstract
The last 25 years have seen remarkable advances in our understanding of the genetic etiologies of dystonia, new approaches into dissecting underlying pathophysiology, and independent progress in identifying effective treatments. In this review we highlight some of these advances, especially the genetic findings that have taken us from phenomenological to molecular-based diagnoses. Twenty DYT loci have been designated and 10 genes identified, all based on linkage analyses in families. Hand in hand with these genetic findings, neurophysiological and imaging techniques have been employed that have helped illuminate the similarities and differences among the various etiological dystonia subtypes. This knowledge is just beginning to yield new approaches to treatment including those based on DYT1 animal models. Despite the lag in identifying genetically based therapies, effective treatments, including impressive benefits from deep brain stimulation and botulinum toxin chemodenervation, have marked the last 25 years. The challenge ahead includes continued advancement into understanding dystonia's many underlying causes and associated pathology and using this knowledge to advance treatment including preventing genetic disease expression.
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Affiliation(s)
- Laurie J Ozelius
- Department of Genetics and Genomic Sciences, Mount Sinai School of Medicine, New York, New York, USA
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10
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Waite A, De Rosa MC, Brancaccio A, Blake DJ. A gain-of-glycosylation mutation associated with myoclonus-dystonia syndrome affects trafficking and processing of mouse ε-sarcoglycan in the late secretory pathway. Hum Mutat 2011; 32:1246-58. [PMID: 21796726 DOI: 10.1002/humu.21561] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 06/20/2011] [Indexed: 11/07/2022]
Abstract
Missense mutations in the SGCE gene encoding ε-sarcoglycan account for approximately 15% of SGCE-positive cases of myoclonus-dystonia syndrome (MDS) in humans. In this study, we show that while the majority of MDS-associated missense mutants modeled with a murine ε-sarcoglycan cDNA are substrates for endoplasmic reticulum-associated degradation, one mutant, M68T (analogous to human c.275T>C, p.M92T), located in the Ig-like domain of ε-sarcoglycan, results in a gain-of-glycosylation mutation producing a protein that is targeted to the plasma membrane, albeit at reduced levels compared to wild-type ε-sarcoglycan. Removal of the ectopic N-linked glycan failed to restore efficient plasma membrane targeting of M68T demonstrating that the substitution rather than the glycan was responsible for the trafficking defect of this mutant. M68T also colocalized with CD63-positive vesicles in the endosomal-lysosomal system and was found to be more susceptible to lysosomal proteolysis than wild-type ε-sarcoglycan. Finally, we demonstrate impaired ectodomain shedding of M68T, a process that occurs physiologically for ε-sarcoglycan resulting in the lysosomal trafficking of the intracellular C-terminal domain of the protein. Our findings show that functional analysis of rare missense mutations can provide a mechanistic insight into the pathogenesis of MDS and the physiological role of ε-sarcoglycan.
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Affiliation(s)
- Adrian Waite
- Department of Psychological Medicine and Neurology, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Heath Park, Cardiff, UK
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11
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Abstract
Myoclonus dystonia syndrome (MDS) refers to a group of heterogeneous nondegenerative clinical conditions characterized by the association of myoclonus and dystonia as the only or prominent symptom. The "core" of MDS is represented by inherited myoclonus-dystonia (M-D), a disorder with autosomal-dominant inheritance and reduced penetrance, beginning in early childhood with a relatively benign course, with myoclonus as the most predominant and disabling symptom. Alcohol responsiveness and psychiatric symptoms are characteristic features. Mutations in the epsilon-sarcoglycan gene (SGCE, DYT11) represent the major genetic cause, but M-D is genetically heterogeneous. In a variable proportion of M-D patients no mutation is found, and at least one other locus (DYT15) has been linked to the disease. Patients with primary dystonia, with or without the DYT1 mutation, may show irregular and arrhythmic jerky movements associated with dystonia. Usually dystonia is the prominent symptom and the myoclonic jerk involves the same body region; this condition, currently defined as "myoclonic dystonia," is included in the spectrum of MDS. Dopa-responsive dystonia due to mutation in the GTP-CH gene and vitamin E deficiency can present with a phenotype of dystonia and myoclonus in combination; both conditions should be considered in the diagnostic approach to patients since they are potentially treatable.
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Affiliation(s)
- Nardo Nardocci
- Department of Child Neurology, Fondazione IRCCS Istituto Neurologico "C. Besta", Milan, Italy.
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Huang CL, Lan MY, Chang YY, Hsu CY, Lai SC, Chen RS, Chang HC, Lu CS, Wu-Chou YH. Large SGCE deletion contributes to Taiwanese myoclonus–dystonia syndrome. Parkinsonism Relat Disord 2010; 16:585-9. [DOI: 10.1016/j.parkreldis.2010.06.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 06/09/2010] [Accepted: 06/11/2010] [Indexed: 11/29/2022]
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Saugier-Veber P, Doummar D, Barthez MA, Czernecki V, Drouot N, Apartis E, Bürglen L, Frebourg T, Roze E. Myoclonus dystonia plus syndrome due to a novel 7q21 microdeletion. Am J Med Genet A 2010; 152A:1244-9. [PMID: 20425829 DOI: 10.1002/ajmg.a.33369] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Myoclonus dystonia (M-D) is a rare genetic movement disorder characterized by a combination of myoclonic jerks and dystonia. It is usually due to mutations in the SGCE gene. We report on a patient with a typical M-D syndrome, but also short stature, microcephaly, and mental retardation. Molecular analysis showed no mutations within the SGCE gene but a microdeletion encompassing the SGCE gene in chromosome region 7q21. Array-CGH analysis showed that the deletion spanned approximately 1.88 Mb. We suggest that M-D plus patients with mental retardation, microcephaly, dysmorphism, or short stature, all frequently associated disorders, should be screened for 7q21 microdeletion. By examining previously published cases of mental retardation associated with pure 7q21 deletions, we identified two distinct regions of respectively 455 and 496 kb that are critical for mental retardation and growth retardation. Among the genes located within these regions, LOC253012, also known as HEPACAM2, is a good candidate for both mental retardation and microcephaly.
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A complex chromosome 7q rearrangement identified in a patient with mental retardation, anxiety disorder, and autistic features. Am J Med Genet A 2010; 152A:427-33. [DOI: 10.1002/ajmg.a.33203] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Is psychopathology part of the phenotypic spectrum of myoclonus-dystonia?: a study of a large Dutch M-D family. Cogn Behav Neurol 2009; 22:127-33. [PMID: 19506430 DOI: 10.1097/wnn.0b013e3181a7228f] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Myoclonus-dystonia (M-D) is a movement disorder frequently caused by mutations in the epsilon-sarcoglycan gene (SGCE, DYT11). In several M-D families, psychiatric symptoms accompanying the motor symptoms have been reported, but a shared genetic etiology remains unclear. OBJECTIVE To assess neuropsychologic functioning and psychopathology in DYT11 mutation carriers (MC) and their family members using standardized neuropsychologic and psychiatric measures. METHODS Cognitive and behavioural characteristics of 27 DYT11 MC (14 symptomatic and 13 asymptomatic) and 42 control subjects from 1 large Dutch M-D family were studied. Neuropsychologic tests encompassed memory, language, mental speed, concentration, visuospatial function, and executive functions. Psychiatric assessment addressed qualitative (according to Diagnostic and Statistical Manual-IV criteria) as well as quantitative measures of depression, anxiety, panic attacks, and obsessive-compulsive disorder (OCD), using selfadministered and interview-based scales. RESULTS No differences were observed on tests of cognitive functioning between DYT11 MC and controls. The frequency of Diagnostic and Statistical Manual-IV diagnoses was higher in the symptomatic DYT11 MC than in controls. The symptomatic DYT11 MC showed more depressive and anxiety symptoms, including panic attacks but no increase of OCD compared with controls. No differences were found between asymptomatic DYT11 MC and controls on any of the psychopathologic tests. CONCLUSIONS Neither cognitive dysfunction nor OCD seems to be associated with the DYT11 phenotype in this large Dutch pedigree. Depressive and anxiety symptoms are increased in symptomatic, but not in asymptomatic DYT11 MC. Future research has to be carried out to determine whether the psychiatric symptoms are part of or secondary to the DYT11 phenotype.
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Kinugawa K, Vidailhet M, Clot F, Apartis E, Grabli D, Roze E. Myoclonus-dystonia: an update. Mov Disord 2009; 24:479-89. [PMID: 19117361 DOI: 10.1002/mds.22425] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Our knowledge of the clinical, neurophysiological, and genetic aspects of myoclonus-dystonia (M-D) has improved markedly in the recent years. Basic research has provided new insights into the complex dysfunctions involved in the pathogenesis of M-D. On the basis of a comprehensive literature search, this review summarizes current knowledge on M-D, with a focus on recent findings. We also propose modified diagnostic criteria and recommendations for clinical management.
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Luciano MS, Ozelius L, Sims K, Raymond D, Liu L, Saunders-Pullman R. Responsiveness to levodopa in epsilon-sarcoglycan deletions. Mov Disord 2009; 24:425-8. [PMID: 19133653 DOI: 10.1002/mds.22375] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Myoclonus-dystonia (M-D) is characterized by early-onset myoclonus and dystonia, and is often due to mutations in the epsilon-sarcoglycan gene (SCGE) at locus 7q21. The pathogenesis of M-D is poorly understood, and in a murine knockout model, dopaminergic hyperactivity has been postulated as a mechanism. We present two unrelated individuals with M-D due to SCGE deletions who displayed a robust and sustained response to levodopa (L-dopa) treatment. In contrast to using dopamine blocking agents suggested by the hyperdopaminergic knockout model, we propose that a trial of L-dopa may be considered in patients with myoclonus-dystonia.
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Affiliation(s)
- Marta San Luciano
- Department of Neurology, Beth Israel Medical Center, New York, New York 10003, USA
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Crespi B. Genomic imprinting in the development and evolution of psychotic spectrum conditions. Biol Rev Camb Philos Soc 2008; 83:441-93. [PMID: 18783362 DOI: 10.1111/j.1469-185x.2008.00050.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
I review and evaluate genetic and genomic evidence salient to the hypothesis that the development and evolution of psychotic spectrum conditions have been mediated in part by alterations of imprinted genes expressed in the brain. Evidence from the genetics and genomics of schizophrenia, bipolar disorder, major depression, Prader-Willi syndrome, Klinefelter syndrome, and other neurogenetic conditions support the hypothesis that the etiologies of psychotic spectrum conditions commonly involve genetic and epigenetic imbalances in the effects of imprinted genes, with a bias towards increased relative effects from imprinted genes with maternal expression or other genes favouring maternal interests. By contrast, autistic spectrum conditions, including Kanner autism, Asperger syndrome, Rett syndrome, Turner syndrome, Angelman syndrome, and Beckwith-Wiedemann syndrome, commonly engender increased relative effects from paternally expressed imprinted genes, or reduced effects from genes favouring maternal interests. Imprinted-gene effects on the etiologies of autistic and psychotic spectrum conditions parallel the diametric effects of imprinted genes in placental and foetal development, in that psychotic spectrum conditions tend to be associated with undergrowth and relatively-slow brain development, whereas some autistic spectrum conditions involve brain and body overgrowth, especially in foetal development and early childhood. An important role for imprinted genes in the etiologies of psychotic and autistic spectrum conditions is consistent with neurodevelopmental models of these disorders, and with predictions from the conflict theory of genomic imprinting.
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Affiliation(s)
- Bernard Crespi
- Department of Biosciences, Simon Fraser University, Burnaby BCV5A1S6, Canada.
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Bonnet C, Grégoire MJ, Vibert M, Raffo E, Leheup B, Jonveaux P. Cryptic 7q21 and 9p23 deletions in a patient with apparently balanced de novo reciprocal translocation t(7;9)(q21;p23) associated with a dystonia-plus syndrome: paternal deletion of the epsilon-sarcoglycan (SGCE) gene. J Hum Genet 2008; 53:876-885. [DOI: 10.1007/s10038-008-0321-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2008] [Accepted: 06/27/2008] [Indexed: 12/11/2022]
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Marshall CR, Young EJ, Pani AM, Freckmann ML, Lacassie Y, Howald C, Fitzgerald KK, Peippo M, Morris CA, Shane K, Priolo M, Morimoto M, Kondo I, Manguoglu E, Berker-Karauzum S, Edery P, Hobart HH, Mervis CB, Zuffardi O, Reymond A, Kaplan P, Tassabehji M, Gregg RG, Scherer SW, Osborne LR. Infantile spasms is associated with deletion of the MAGI2 gene on chromosome 7q11.23-q21.11. Am J Hum Genet 2008; 83:106-11. [PMID: 18565486 DOI: 10.1016/j.ajhg.2008.06.001] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Revised: 05/29/2008] [Accepted: 06/02/2008] [Indexed: 01/14/2023] Open
Abstract
Infantile spasms (IS) is the most severe and common form of epilepsy occurring in the first year of life. At least half of IS cases are idiopathic in origin, with others presumed to arise because of brain insult or malformation. Here, we identify a locus for IS by high-resolution mapping of 7q11.23-q21.1 interstitial deletions in patients. The breakpoints delineate a 500 kb interval within the MAGI2 gene (1.4 Mb in size) that is hemizygously disrupted in 15 of 16 participants with IS or childhood epilepsy, but remains intact in 11 of 12 participants with no seizure history. MAGI2 encodes the synaptic scaffolding protein membrane-associated guanylate kinase inverted-2 that interacts with Stargazin, a protein also associated with epilepsy in the stargazer mouse.
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Han F, Racacho L, Yang H, Read T, Suchowersky O, Lang AE, Grimes DA, Bulman DE. Large deletions account for an increasing number of mutations inSGCE. Mov Disord 2008; 23:456-60. [DOI: 10.1002/mds.21895] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Ming JE, Geiger E, James AC, Ciprero KL, Nimmakayalu M, Zhang Y, Huang A, Vaddi M, Rappaport E, Zackai EH, Shaikh TH. Rapid detection of submicroscopic chromosomal rearrangements in children with multiple congenital anomalies using high density oligonucleotide arrays. Hum Mutat 2006; 27:467-73. [PMID: 16619270 DOI: 10.1002/humu.20322] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Chromosomal rearrangements such as microdeletions and interstitial duplications are the underlying cause of many human genetic disorders. These disorders can manifest in the form of multiple congenital anomalies (MCA), which are a significant cause of morbidity and mortality in children. The major limitations of cytogenetic tests currently used for the detection of such chromosomal rearrangements are low resolution and limited coverage of the genome. Thus, it is likely that children with MCA may have submicroscopic chromosomal rearrangements that are not detectable by current techniques. We report the use of a commercially available, oligonucleotide-based microarray for genome-wide analysis of copy number alterations. First, we validated the microarray in patients with known chromosomal rearrangements. Next, we identified previously undetected, de novo chromosomal deletions in patients with MCA who have had a normal high-resolution karyotype and subtelomeric fluorescence in situ hybridization (FISH) analysis. These findings indicate that high-density, oligonucleotide-based microarrays can be successfully used as tools for the detection of chromosomal rearrangement in clinical samples. Their higher resolution and commercial availability make this type of microarray highly desirable for application in the diagnosis of patients with multiple congenital defects.
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Affiliation(s)
- Jeffrey E Ming
- Division of Human Genetics, Stokes Research Institute, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA
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