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Broman M, Islander G, Müller CR. Malignant hyperthermia, a Scandinavian update. Acta Anaesthesiol Scand 2015; 59:951-61. [PMID: 25989378 DOI: 10.1111/aas.12541] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 03/23/2015] [Accepted: 03/24/2015] [Indexed: 12/15/2022]
Abstract
BACKGROUND Malignant Hyperthermia (MH) is a rare pharmacogenetic disorder, triggered by halogenated anesthetics and/or succinylcholine. In susceptible individuals, these drugs can activate an explosive life threatening clinical reaction. Leading symptoms are hypercarbia, muscle rigidity, and metabolic acidosis. MH is inherited in an autosomal-dominant manner and linked to mutations in the large ryanodine 1 gene (RYR1) gene in the majority of cases. Very few MH patients have been found to carry mutations in the CACNA1S gene. METHODS For this review a large litterature search was carried out and the Swedish MH database consisting of 436 probands who have undergone in vitro muscle contraction test (IVCT) during 1984-2014 was analyzed. RESULTS Twelve different MH causative mutations have been found in Swedish patients so far. These mutations lead to a disturbed calcium balance in striated muscle tissue. A muscle biopsy for the IVCT or finding of an approved causative mutation are required for the diagnosis. CONCLUSION A Malignant Hyperthermia susceptible (MHS) patient should be anesthetized with trigger-free anesthesia. There are a few reports of MH-like reactions in patients unrelated to anesthesia. The outcome is dependent on early recognizing of the reaction and fast disconnection of the trigger agents and administration of dantrolene.
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Affiliation(s)
- M. Broman
- Perioperative and Intensive Care; Skåne University Hospital; Lund Sweden
| | - G. Islander
- Perioperative and Intensive Care; Skåne University Hospital; Lund Sweden
| | - C. R. Müller
- Biocentre; Institute for Human Genetics; Würzburg University; Würzburg Germany
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Rosenberg H, Pollock N, Schiemann A, Bulger T, Stowell K. Malignant hyperthermia: a review. Orphanet J Rare Dis 2015; 10:93. [PMID: 26238698 PMCID: PMC4524368 DOI: 10.1186/s13023-015-0310-1] [Citation(s) in RCA: 296] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Accepted: 07/22/2015] [Indexed: 02/06/2023] Open
Abstract
Malignant hyperthermia (MH) is a pharmacogenetic disorder of skeletal muscle that presents as a hypermetabolic response to potent volatile anesthetic gases such as halothane, sevoflurane, desflurane, isoflurane and the depolarizing muscle relaxant succinylcholine, and rarely, in humans, to stressors such as vigorous exercise and heat. The incidence of MH reactions ranges from 1:10,000 to 1: 250,000 anesthetics. However, the prevalence of the genetic abnormalities may be as great as one in 400 individuals. MH affects humans, certain pig breeds, dogs and horses. The classic signs of MH include hyperthermia, tachycardia, tachypnea, increased carbon dioxide production, increased oxygen consumption, acidosis, hyperkalaemia, muscle rigidity, and rhabdomyolysis, all related to a hypermetabolic response. The syndrome is likely to be fatal if untreated. An increase in end-tidal carbon dioxide despite increased minute ventilation provides an early diagnostic clue. In humans the syndrome is inherited in an autosomal dominant pattern, while in pigs it is autosomal recessive. Uncontrolled rise of myoplasmic calcium, which activates biochemical processes related to muscle activation leads to the pathophysiologic changes. In most cases, the syndrome is caused by a defect in the ryanodine receptor. Over 400 variants have been identified in the RYR1 gene located on chromosome 19q13.1, and at least 34 are causal for MH. Less than 1 % of variants have been found in CACNA1S but not all of these are causal. Diagnostic testing involves the in vitro contracture response of biopsied muscle to halothane, caffeine, and in some centres ryanodine and 4-chloro-m-cresol. Elucidation of the genetic changes has led to the introduction of DNA testing for susceptibility to MH. Dantrolene sodium is a specific antagonist and should be available wherever general anesthesia is administered. Increased understanding of the clinical manifestation and pathophysiology of the syndrome, has lead to the mortality decreasing from 80 % thirty years ago to <5 % in 2006.
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Affiliation(s)
- Henry Rosenberg
- Department of Medical Education and Clinical Research, Saint Barnabas Medical Center, Livingston, NJ, 07039, USA.
| | - Neil Pollock
- Department of Anesthesia and Intensive Care, Palmerston North Hospital, Palmerston North, New Zealand.
| | - Anja Schiemann
- Institute of Fundamental Sciences, Massey University, Palmerston North, New Zealand.
| | - Terasa Bulger
- Department of Anesthesia and Intensive Care, Palmerston North Hospital, Palmerston North, New Zealand.
| | - Kathryn Stowell
- Institute of Fundamental Sciences, Massey University, Palmerston North, New Zealand.
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Snoeck M, van Engelen BGM, Küsters B, Lammens M, Meijer R, Molenaar JPF, Raaphorst J, Verschuuren-Bemelmans CC, Straathof CSM, Sie LTL, de Coo IF, van der Pol WL, de Visser M, Scheffer H, Treves S, Jungbluth H, Voermans NC, Kamsteeg EJ. RYR1-related myopathies: a wide spectrum of phenotypes throughout life. Eur J Neurol 2015; 22:1094-112. [PMID: 25960145 DOI: 10.1111/ene.12713] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 02/06/2015] [Indexed: 12/17/2022]
Abstract
BACKGROUND AND PURPOSE Although several recent studies have implicated RYR1 mutations as a common cause of various myopathies and the malignant hyperthermia susceptibility (MHS) trait, many of these studies have been limited to certain age groups, confined geographical regions or specific conditions. The aim of the present study was to investigate the full spectrum of RYR1-related disorders throughout life and to use this knowledge to increase vigilance concerning malignant hyperthermia. METHODS A retrospective cohort study was performed on the clinical, genetic and histopathological features of all paediatric and adult patients in whom an RYR1 mutation was detected in a national referral centre for both malignant hyperthermia and inherited myopathies (2008-2012). RESULTS The cohort of 77 non-related patients (detection rate 28%) included both congenital myopathies with permanent weakness and 'induced' myopathies such as MHS and non-anaesthesia-related episodes of rhabdomyolysis or hyperCKemia, manifested throughout life and triggered by various stimuli. Sixty-one different mutations were detected, of which 24 were novel. Some mutations are present in both dominant (MHS) and recessive modes (congenital myopathy) of inheritance, even within families. Histopathological features included an equally wide spectrum, ranging from only subtle abnormalities to prominent cores. CONCLUSIONS This broad range of RYR1-related disorders often presents to the general paediatric and adult neurologist. Its recognition is essential for genetic counselling and improving patients' safety during anaesthesia. Future research should focus on in vitro testing by the in vitro contracture test and functional characterization of the large number of RYR1 variants whose precise effects currently remain uncertain.
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Affiliation(s)
- M Snoeck
- National MH Investigation Unit, Department of Anesthesiology, Canisius Wilhelmina Hospital, Nijmegen, The Netherlands
| | - B G M van Engelen
- Department of Neurology, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - B Küsters
- Department of Pathology, Radboud University Medical Centre, Nijmegen, The Netherlands.,Department of Pathology, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - M Lammens
- Department of Pathology, Radboud University Medical Centre, Nijmegen, The Netherlands.,Department of Pathology, Antwerp University Hospital, University of Antwerp, Edegem, Belgium
| | - R Meijer
- Department of Human Genetics, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - J P F Molenaar
- Department of Neurology, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - J Raaphorst
- Department of Neurology, Radboud University Medical Centre, Nijmegen, The Netherlands.,Department of Neurology, Academic Medical Centre, Amsterdam, The Netherlands
| | - C C Verschuuren-Bemelmans
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - C S M Straathof
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands
| | - L T L Sie
- Department of Neuropediatrics, Juliana Children's Hospital/Haga Hospital, The Hague, Nijmegen, The Netherlands
| | - I F de Coo
- Department of Neurology, Erasmus Medical Centre, Rotterdam, The Netherlands
| | - W L van der Pol
- Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - M de Visser
- Department of Neurology, Academic Medical Centre, Amsterdam, The Netherlands
| | - H Scheffer
- Department of Human Genetics, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - S Treves
- Departments of Anesthesia and Biomedicine, University Hospital Basel, Basel, Switzerland
| | - H Jungbluth
- Department of Paediatric Neurology, Neuromuscular Service, Evelina Children's Hospital, Guy's and St Thomas' Hospital NHS Foundation Trust, London, UK.,Randall Division for Cell and Molecular Biophysics, Muscle Signalling Section, King's College, London, UK.,Department of Basic and Clinical Neuroscience, IoPPN, King's College, London, UK
| | - N C Voermans
- Department of Neurology, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - E-J Kamsteeg
- Department of Human Genetics, Radboud University Medical Centre, Nijmegen, The Netherlands
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54
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Scalco RS, Gardiner AR, Pitceathly RD, Zanoteli E, Becker J, Holton JL, Houlden H, Jungbluth H, Quinlivan R. Rhabdomyolysis: a genetic perspective. Orphanet J Rare Dis 2015; 10:51. [PMID: 25929793 PMCID: PMC4522153 DOI: 10.1186/s13023-015-0264-3] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 04/09/2015] [Indexed: 01/19/2023] Open
Abstract
Rhabdomyolysis (RM) is a clinical emergency characterized by fulminant skeletal muscle damage and release of intracellular muscle components into the blood stream leading to myoglobinuria and, in severe cases, acute renal failure. Apart from trauma, a wide range of causes have been reported including drug abuse and infections. Underlying genetic disorders are also a cause of RM and can often pose a diagnostic challenge, considering their marked heterogeneity and comparative rarity. In this paper we review the range of rare genetic defects known to be associated with RM. Each gene has been reviewed for the following: clinical phenotype, typical triggers for RM and recommended diagnostic approach. The purpose of this review is to highlight the most important features associated with specific genetic defects in order to aid the diagnosis of patients presenting with hereditary causes of recurrent RM.
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Affiliation(s)
- Renata Siciliani Scalco
- MRC Centre for Neuromuscular Diseases and Department of Molecular Neuroscience, University College London (UCL) Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK. .,Department of Neurology, HSL, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, Rio Grande do Sul, Brazil. .,CAPES Foundation, Ministry of Education of Brazil, Brasilia, DF, Brazil.
| | - Alice R Gardiner
- MRC Centre for Neuromuscular Diseases and Department of Molecular Neuroscience, University College London (UCL) Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK.
| | - Robert Ds Pitceathly
- MRC Centre for Neuromuscular Diseases and Department of Molecular Neuroscience, University College London (UCL) Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK. .,Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London (KCL), London, UK.
| | - Edmar Zanoteli
- Department of Neurology, School of Medicine, Universidade de São Paulo (FMUSP), São Paulo, SP, Brazil.
| | - Jefferson Becker
- Department of Neurology, HSL, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, Rio Grande do Sul, Brazil.
| | - Janice L Holton
- MRC Centre for Neuromuscular Diseases and Department of Molecular Neuroscience, University College London (UCL) Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK.
| | - Henry Houlden
- MRC Centre for Neuromuscular Diseases and Department of Molecular Neuroscience, University College London (UCL) Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK.
| | - Heinz Jungbluth
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London (KCL), London, UK. .,Department of Paediatric Neurology, Evelina Children's Hospital, Guy's & St Thomas NHS Foundation Trust, London, UK. .,Randall Division for Cell and Molecular Biophysics, Muscle Signalling Section, King's College London, London, UK.
| | - Ros Quinlivan
- MRC Centre for Neuromuscular Diseases and Department of Molecular Neuroscience, University College London (UCL) Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK. .,Dubowitz Neuromuscular Centre, Great Ormond Street Hospital, London, UK.
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55
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Colombo I, Scoto M, Manzur AY, Robb SA, Maggi L, Gowda V, Cullup T, Yau M, Phadke R, Sewry C, Jungbluth H, Muntoni F. Congenital myopathies: Natural history of a large pediatric cohort. Neurology 2014; 84:28-35. [PMID: 25428687 DOI: 10.1212/wnl.0000000000001110] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
OBJECTIVE To assess the natural history of congenital myopathies (CMs) due to different genotypes. METHODS Retrospective cross-sectional study based on case-note review of 125 patients affected by CM, followed at a single pediatric neuromuscular center, between 1984 and 2012. RESULTS Genetic characterization was achieved in 99 of 125 cases (79.2%), with RYR1 most frequently implicated (44/125). Neonatal/infantile onset was observed in 76%. At birth, 30.4% required respiratory support, and 25.2% nasogastric feeding. Twelve percent died, mainly within the first year, associated with mutations in ACTA1, MTM1, or KLHL40. All RYR1-mutated cases survived and did not require long-term ventilator support including those with severe neonatal onset; however, recessive cases were more likely to require gastrostomy insertion (p = 0.0028) compared with dominant cases. Independent ambulation was achieved in 74.1% of all patients; 62.9% were late walkers. Among ambulant patients, 9% eventually became wheelchair-dependent. Scoliosis of variable severity was reported in 40%, with 1/3 of (both ambulant and nonambulant) patients requiring surgery. Bulbar involvement was present in 46.4% and required gastrostomy placement in 28.8% (at a mean age of 2.7 years). Respiratory impairment of variable severity was a feature in 64.1%; approximately half of these patients required nocturnal noninvasive ventilation due to respiratory failure (at a mean age of 8.5 years). CONCLUSIONS We describe the long-term outcome of a large cohort of patients with CMs. While overall course is stable, we demonstrate a wide clinical spectrum with motor deterioration in a subset of cases. Severity in the neonatal/infantile period is critical for survival, with clear genotype-phenotype correlations that may inform future counseling.
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Affiliation(s)
- Irene Colombo
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK
| | - Mariacristina Scoto
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK
| | - Adnan Y Manzur
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK
| | - Stephanie A Robb
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK
| | - Lorenzo Maggi
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK
| | - Vasantha Gowda
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK
| | - Thomas Cullup
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK
| | - Michael Yau
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK
| | - Rahul Phadke
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK
| | - Caroline Sewry
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK
| | - Heinz Jungbluth
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK
| | - Francesco Muntoni
- From the Dubowitz Neuromuscular Centre and MRC Centre for Neuromuscular Disorders (I.C., M.S., A.Y.M., S.A.R., V.G., C.S., F.M.), University College London Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; Neuromuscular Unit (I.C.), Department of Neurological Sciences, IRCCS Foundation Cà Granda, Ospedale Maggiore Policlinico, Dino Ferrari Centre, Milan, University of Milan; Muscle Pathology and Neuroimmunology Unit (L.M.), Foundation IRCCS Neurological Institute C. Besta, Milan, Italy; DNA Laboratory (T.C., M.Y.), GSTS Pathology, Guy's Hospital, London; University College London Department of Neurology (R.P.), National Hospital for Neurology and Neurosurgery, London; Wolfson Centre for Inherited Neuromuscular Diseases RJAH (C.S.), Oswestry; Department of Paediatric Neurology (H.J.), Evelina Children's Hospital, London; Randall Division for Cell and Molecular Biophysics (H.J.), Muscle Signalling Section, King's College, London; and Clinical Neuroscience Division (H.J.), IoP, London, UK.
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56
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Abstract
The triad is a skeletal muscle substructure responsible for the regulation of excitation-contraction coupling. It is formed by the close apposition of the T-tubule and the terminal sarcoplasmic reticulum. A rapidly growing list of skeletal myopathies, here referred to as triadopathies, are caused by gene mutations in components of the triad. These disorders, at their root, are caused by defects in excitation contraction coupling and intracellular calcium homeostasis. Secondary abnormalities in triad structure and/or function are also reported in several muscle diseases, most notably certain muscular dystrophies. This review highlights the current understanding of both primary and secondary triadopathies, and identifies important concepts yet to be fully addressed in the field. The emphasis of the review is both on the pathogenesis of triadopathies and their potential treatment.
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Affiliation(s)
- James J Dowling
- Division of Neurology and Genetics and Genome Biology Program, Hospital for Sick Children, Toronto, ON, Canada,
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57
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Abstract
Pediatric patients often undergo anesthesia for ambulatory procedures. This article discusses several common preoperative dilemmas, including whether to postpone anesthesia when a child has an upper respiratory infection, whether to test young women for pregnancy, which children require overnight admission for apnea monitoring, and the effectiveness of nonpharmacological techniques for reducing anxiety. Medication issues covered include the risks of anesthetic agents in children with undiagnosed weakness, the use of remifentanil for tracheal intubation, and perioperative dosing of rectal acetaminophen. The relative merits of caudal and dorsal penile nerve block for pain after circumcision are also discussed.
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Affiliation(s)
- David A August
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, 55 Fruit Street, GRB-444, Boston, MA 02114, USA.
| | - Lucinda L Everett
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, 55 Fruit Street, GRB-415, Boston, MA 02114, USA
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North KN, Wang CH, Clarke N, Jungbluth H, Vainzof M, Dowling JJ, Amburgey K, Quijano-Roy S, Beggs AH, Sewry C, Laing NG, Bönnemann CG. Approach to the diagnosis of congenital myopathies. Neuromuscul Disord 2014; 24:97-116. [PMID: 24456932 PMCID: PMC5257342 DOI: 10.1016/j.nmd.2013.11.003] [Citation(s) in RCA: 176] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 11/06/2013] [Accepted: 11/08/2013] [Indexed: 10/26/2022]
Abstract
Over the past decade there have been major advances in defining the genetic basis of the majority of congenital myopathy subtypes. However the relationship between each congenital myopathy, defined on histological grounds, and the genetic cause is complex. Many of the congenital myopathies are due to mutations in more than one gene, and mutations in the same gene can cause different muscle pathologies. The International Standard of Care Committee for Congenital Myopathies performed a literature review and consulted a group of experts in the field to develop a summary of (1) the key features common to all forms of congenital myopathy and (2) the specific features that help to discriminate between the different genetic subtypes. The consensus statement was refined by two rounds of on-line survey, and a three-day workshop. This consensus statement provides guidelines to the physician assessing the infant or child with hypotonia and weakness. We summarise the clinical features that are most suggestive of a congenital myopathy, the major differential diagnoses and the features on clinical examination, investigations, muscle pathology and muscle imaging that are suggestive of a specific genetic diagnosis to assist in prioritisation of genetic testing of known genes. As next generation sequencing becomes increasingly used as a diagnostic tool in clinical practise, these guidelines will assist in determining which sequence variations are likely to be pathogenic.
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Affiliation(s)
- Kathryn N North
- Murdoch Childrens Research Institute, Royal Children's Hospital, Flemington Road, Parkville, Melbourne, Victoria 3052, Australia; Institute for Neuroscience and Muscle Research, The Children's Hospital at Westmead, University of Sydney, Sydney, Australia.
| | - Ching H Wang
- Driscoll Children's Hospital, Corpus Christi, TX, United States
| | - Nigel Clarke
- Institute for Neuroscience and Muscle Research, The Children's Hospital at Westmead, University of Sydney, Sydney, Australia
| | - Heinz Jungbluth
- Evelina Children's Hospital, Department of Paediatric Neurology, London, United Kingdom; Randall Division for Cell and Molecular Biophysics, Muscle Signalling Section, King's College, London, United Kingdom; Clinical Neuroscience Division, IoP, London, United Kingdom
| | - Mariz Vainzof
- Human Genome Research Center, University of Sao Paulo, Sao Paulo, Brazil
| | - James J Dowling
- Division of Neurology, Department of Paediatrics, Hospital for Sick Children, Toronto, ON, Canada
| | - Kimberly Amburgey
- Division of Neurology, Department of Paediatrics, Hospital for Sick Children, Toronto, ON, Canada
| | - Susana Quijano-Roy
- Department of Pediatrics, Garches Neuromuscular Reference Center (GNMH), APHP Raymond Poincare University Hospital (UVSQ), Garches, France
| | - Alan H Beggs
- Children's Hospital Boston, Boston, MA, United States
| | - Caroline Sewry
- Dubowitz Neuromuscular Centre, London, United Kingdom; Wolfson Centre of Inherited Neuromuscular Diseases, RJAH Orthopaedic Hospital, Oswestry, United Kingdom
| | - Nigel G Laing
- Centre for Medical Research, University of Western Australia and Harry Perkins Institute of Medical Research, QQ Building, QEII Medical Centre, Nedlands, Western Australia 6009, Australia
| | - Carsten G Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, Bethesda, MD, United States
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Brislin RP, Theroux MC. Core myopathies and malignant hyperthermia susceptibility: a review. Paediatr Anaesth 2013; 23:834-41. [PMID: 23617272 DOI: 10.1111/pan.12175] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/09/2013] [Indexed: 11/30/2022]
Abstract
The core myopathies are a subset of myopathies that present in infancy with hypotonia and muscle weakness. They were formerly considered a rare type of congenital myopathy but are now recognized as being more prevalent. Due to their genetic linkage to mutations in the ryanodine receptor gene (RYR1), core myopathies (in particular, central core disease) carry a high risk of malignant hyperthermia susceptibility. In this review article, we describe the phenotypical, genetic, and histopathological characteristics of core myopathies and further describe the currently understood nature of their risk of malignant hyperthermia. We also review the level of suspicion a clinician should exhibit with a child who has a possible core myopathy or other congenital myopathy presenting for an anesthetic prior to a definitive genetic analysis. For this review article, we performed literature searches using the key words anesthesiology, core myopathies, pediatric neurology, malignant hyperthermia, genetics, ryanodine receptor, and molecular biology. We also relied on literature accumulated by the two authors, who served as hotline consultants for the Malignant Hyperthermia Hotline of the Malignant Hyperthermia Association of the United States (MHAUS) for the past 12 years.
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Affiliation(s)
- Robert P Brislin
- Department of Anesthesiology and Critical Care Medicine, Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE 19899, USA.
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60
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Gibbs EM, Horstick EJ, Dowling JJ. Swimming into prominence: the zebrafish as a valuable tool for studying human myopathies and muscular dystrophies. FEBS J 2013; 280:4187-97. [PMID: 23809187 DOI: 10.1111/febs.12412] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 06/07/2013] [Accepted: 06/20/2013] [Indexed: 11/28/2022]
Abstract
A new and exciting phase of muscle disease research has recently been entered. The application of next generation sequencing technology has spurred an unprecedented era of gene discovery for both myopathies and muscular dystrophies. Gene-based therapies for Duchenne muscular dystrophy have entered clinical trial, and several pathway-based therapies are doing so as well for a handful of muscle diseases. While many factors have aided the extraordinary developments in gene discovery and therapy development, the zebrafish model system has emerged as a vital tool in these advancements. In this review, we will highlight how the zebrafish has greatly aided in the identification of new muscle disease genes and in the recognition of novel therapeutic strategies. We will start with a general introduction to the zebrafish as a model, discuss the ways in which muscle disease can be modeled and analyzed in the fish, and conclude with observations from recent studies that highlight the power of the fish as a research tool for muscle disease.
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Affiliation(s)
- Elizabeth M Gibbs
- Departments of Neuroscience, Neurology and Pediatrics, University of Michigan Medical Center, Ann Arbor, MI, USA
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61
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Zhou H, Rokach O, Feng L, Munteanu I, Mamchaoui K, Wilmshurst JM, Sewry C, Manzur AY, Pillay K, Mouly V, Duchen M, Jungbluth H, Treves S, Muntoni F. RyR1 Deficiency in Congenital Myopathies Disrupts Excitation-Contraction Coupling. Hum Mutat 2013; 34:986-96. [DOI: 10.1002/humu.22326] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 03/18/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Haiyan Zhou
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
| | - Ori Rokach
- Department of Anaesthesia and Biomedicine; Basel University and University Hospital Basel; Basel Switzerland
| | - Lucy Feng
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
| | - Iulia Munteanu
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
| | - Kamel Mamchaoui
- UM76 Université Pierre et Marie Curie; UMRS974 INSERM, UMR 7215 CNRS, Institut de Myologie AIM, Groupe hospitalier Pitié-Salpétrière, 47 bd de I'Hôpital; Paris France
| | - Jo M. Wilmshurst
- Department of Paediatric Neurology; School of Child and Adolescent Health, University of Cape Town, Red Cross Children's Hospital; Cape Town South Africa
| | - Caroline Sewry
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
| | - Adnan Y. Manzur
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
| | - Komala Pillay
- Department of Paediatric Pathology; School of Child and Adolescent Health, University of Cape Town, Red Cross Children's Hospital; Cape Town South Africa
| | - Vincent Mouly
- Department of Anaesthesia and Biomedicine; Basel University and University Hospital Basel; Basel Switzerland
| | - Michael Duchen
- Cell and Developmental Biology; University College London; London UK
| | - Heinz Jungbluth
- Department of Paediatric Neurology; Evelina Children's Hospital; London UK
- Clinical Neuroscience Division; IoP, King's College; London UK
- Randall Division of Cell and Molecular Biophysics; Muscle Signalling Group; King's College London; London UK
| | - Susan Treves
- Department of Anaesthesia and Biomedicine; Basel University and University Hospital Basel; Basel Switzerland
- Department of Life Sciences; University of Ferrara; Ferrara Italy
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre; Institute of Child Health, University College London; London UK
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A novel late-onset axial myopathy associated with mutations in the skeletal muscle ryanodine receptor (RYR1) gene. J Neurol 2013; 260:1504-10. [DOI: 10.1007/s00415-012-6817-7] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 12/17/2012] [Accepted: 12/19/2012] [Indexed: 11/27/2022]
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Klein A, Lillis S, Munteanu I, Scoto M, Zhou H, Quinlivan R, Straub V, Manzur AY, Roper H, Jeannet PY, Rakowicz W, Jones DH, Jensen UB, Wraige E, Trump N, Schara U, Lochmuller H, Sarkozy A, Kingston H, Norwood F, Damian M, Kirschner J, Longman C, Roberts M, Auer-Grumbach M, Hughes I, Bushby K, Sewry C, Robb S, Abbs S, Jungbluth H, Muntoni F. Clinical and genetic findings in a large cohort of patients with ryanodine receptor 1 gene-associated myopathies. Hum Mutat 2012; 33:981-8. [PMID: 22473935 DOI: 10.1002/humu.22056] [Citation(s) in RCA: 124] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Accepted: 02/07/2012] [Indexed: 11/12/2022]
Abstract
Ryanodine receptor 1 (RYR1) mutations are a common cause of congenital myopathies associated with both dominant and recessive inheritance. Histopathological findings frequently feature central cores or multi-minicores, more rarely, type 1 predominance/uniformity, fiber-type disproportion, increased internal nucleation, and fatty and connective tissue. We describe 71 families, 35 associated with dominant RYR1 mutations and 36 with recessive inheritance. Five of the dominant mutations and 35 of the 55 recessive mutations have not been previously reported. Dominant mutations, typically missense, were frequently located in recognized mutational hotspot regions, while recessive mutations were distributed throughout the entire coding sequence. Recessive mutations included nonsense and splice mutations expected to result in reduced RyR1 protein. There was wide clinical variability. As a group, dominant mutations were associated with milder phenotypes; patients with recessive inheritance had earlier onset, more weakness, and functional limitations. Extraocular and bulbar muscle involvement was almost exclusively observed in the recessive group. In conclusion, our study reports a large number of novel RYR1 mutations and indicates that recessive variants are at least as frequent as the dominant ones. Assigning pathogenicity to novel mutations is often difficult, and interpretation of genetic results in the context of clinical, histological, and muscle magnetic resonance imaging findings is essential.
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Affiliation(s)
- Andrea Klein
- Paediatric Neurology, University Children's Hospital Zurich, Zurich, Switzerland
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64
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Wang CH, Dowling JJ, North K, Schroth MK, Sejersen T, Shapiro F, Bellini J, Weiss H, Guillet M, Amburgey K, Apkon S, Bertini E, Bonnemann C, Clarke N, Connolly AM, Estournet-Mathiaud B, Fitzgerald D, Florence JM, Gee R, Gurgel-Giannetti J, Glanzman AM, Hofmeister B, Jungbluth H, Koumbourlis AC, Laing NG, Main M, Morrison LA, Munns C, Rose K, Schuler PM, Sewry C, Storhaug K, Vainzof M, Yuan N. Consensus statement on standard of care for congenital myopathies. J Child Neurol 2012; 27:363-82. [PMID: 22431881 PMCID: PMC5234865 DOI: 10.1177/0883073812436605] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Recent progress in scientific research has facilitated accurate genetic and neuropathological diagnosis of congenital myopathies. However, given their relatively low incidence, congenital myopathies remain unfamiliar to the majority of care providers, and the levels of patient care are extremely variable. This consensus statement aims to provide care guidelines for congenital myopathies. The International Standard of Care Committee for Congenital Myopathies worked through frequent e-mail correspondences, periodic conference calls, 2 rounds of online surveys, and a 3-day workshop to achieve a consensus for diagnostic and clinical care recommendations. The committee includes 59 members from 10 medical disciplines. They are organized into 5 working groups: genetics/diagnosis, neurology, pulmonology, gastroenterology/nutrition/speech/oral care, and orthopedics/rehabilitation. In each care area the authors summarize the committee's recommendations for symptom assessments and therapeutic interventions. It is the committee's goal that through these recommendations, patients with congenital myopathies will receive optimal care and improve their disease outcome.
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Affiliation(s)
- Ching H. Wang
- Stanford University School of Medicine, Stanford, CA, USA
| | | | | | - Mary K. Schroth
- University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | | | | | | | - Hali Weiss
- Stanford University School of Medicine, Stanford, CA, USA
| | - Marc Guillet
- A Foundation Building Strength, Palo Alto, CA, USA
| | | | - Susan Apkon
- Seattle Children’s Hospital, Seattle, WA, USA
| | | | | | | | | | | | | | | | - Richard Gee
- Stanford University School of Medicine, Stanford, CA, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | - Kari Storhaug
- National Resource Centre for Oral Health in Rare Medical Conditions, Oslo Norway
| | | | - Nanci Yuan
- Stanford University School of Medicine, Stanford, CA, USA
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Jungbluth H, Dowling JJ, Ferreiro A, Muntoni F. 182nd ENMC International Workshop: RYR1-related myopathies, 15-17th April 2011, Naarden, The Netherlands. Neuromuscul Disord 2012; 22:453-62. [PMID: 22226685 DOI: 10.1016/j.nmd.2011.12.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Accepted: 12/04/2011] [Indexed: 11/15/2022]
Affiliation(s)
- Heinz Jungbluth
- Clinical Neuroscience Division, IOP, King's College, London, United Kingdom.
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66
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Abstract
Congenital fiber-type disproportion is a form of congenital myopathy that may be best viewed as a syndrome rather than as a formal diagnosis. The central histologic abnormality is that type 1 fibers are consistently smaller than type 2 fibers by at least 35%-40%. Care is needed in diagnosing patients, as this histologic abnormality can occur in other congenital myopathies and in other neuromuscular disorders. Many of the genetic causes have been identified. Careful surveillance of respiratory function is required in all patients until the specific genetic cause is known and advice can be individualized.
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Affiliation(s)
- Nigel F Clarke
- Institute of Neuroscience and Muscle Research, Children's Hospital at Westmead, Discipline of Paediatrics & Child Health, University of Sydney, Westmead, New South Wales, Australia.
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67
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Abstract
The core myopathies, Central Core Disease and Multiminicore Disease, are heterogeneous congenital myopathies with the common defining histopathological feature of focally reduced oxidative enzyme activity (central cores, multiminicores). Mutations in the gene encoding for the skeletal muscle ryanodine (RyR1) receptor are the most common cause. Mutations in the selenoprotein N (SEPN1) gene cause a less common variant. Pathogenic mechanisms underlying dominant RYR1 mutations have been extensively characterized, whereas those associated with recessive RYR1 and SEPN1 mutations are emerging. Identifying a specific genetic defect from the histopathological diagnosis of a core myopathy is complex and ought to be informed by a combined appraisal of histopathological, clinical, and, increasingly, muscle magnetic resonance imaging data. The present review aims at giving an overview of the main genetic and clinicopathological findings, with a major emphasis on features likely to inform the diagnostic process, as well as current treatments and perspectives for future research.
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Affiliation(s)
- Heinz Jungbluth
- Clinical Neuroscience Division, Institute of Psychiatry, King's College London, London, UK.
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Chorna T, Hasan G. The genetics of calcium signaling in Drosophila melanogaster. Biochim Biophys Acta Gen Subj 2011; 1820:1269-82. [PMID: 22100727 DOI: 10.1016/j.bbagen.2011.11.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Revised: 10/31/2011] [Accepted: 11/02/2011] [Indexed: 01/13/2023]
Abstract
BACKGROUND Genetic screens for behavioral and physiological defects in Drosophila melanogaster, helped identify several components of calcium signaling of which some, like the Trps, were novel. For genes initially identified in vertebrates, reverse genetic methods have allowed functional studies at the cellular and systemic levels. SCOPE OF REVIEW The aim of this review is to explain how various genetic methods available in Drosophila have been used to place different arms of Ca2+ signaling in the context of organismal development, physiology and behavior. MAJOR CONCLUSION Mutants generated in genes encoding a range of Ca2+ transport systems, binding proteins and enzymes affect multiple aspects of neuronal and muscle physiology. Some also affect the maintenance of ionic balance and excretion from malpighian tubules and innate immune responses in macrophages. Aspects of neuronal physiology affected include synaptic growth and plasticity, sensory transduction, flight circuit development and function. Genetic interaction screens have shown that mechanisms of maintaining Ca2+ homeostasis in Drosophila are cell specific and require a synergistic interplay between different intracellular and plasma membrane Ca2+ signaling molecules. GENERAL SIGNIFICANCE Insights gained through genetic studies of conserved Ca2+ signaling pathways have helped understand multiple aspects of fly physiology. The similarities between mutant phenotypes of Ca2+ signaling genes in Drosophila with certain human disease conditions, especially where homologous genes are causative factors, are likely to aid in the discovery of underlying disease mechanisms and help develop novel therapeutic strategies. This article is part of a Special Issue entitled Biochemical, biophysical and genetic approaches to intracellular calcium signalling.
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Affiliation(s)
- Tetyana Chorna
- National Center for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India
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69
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Lillis S, Abbs S, Mueller CR, Muntoni F, Jungbluth H. Clinical utility gene card for: Central core disease. Eur J Hum Genet 2011; 20:ejhg2011179. [PMID: 21989361 DOI: 10.1038/ejhg.2011.179] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Suzanne Lillis
- GSTS Pathology, Guy's Hospital, Great Maze Pond, London, UK
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