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Inamori KI, Willer T, Hara Y, Venzke D, Anderson ME, Clarke NF, Guicheney P, Bönnemann CG, Moore SA, Campbell KP. Endogenous glucuronyltransferase activity of LARGE or LARGE2 required for functional modification of α-dystroglycan in cells and tissues. J Biol Chem 2014; 289:28138-48. [PMID: 25138275 DOI: 10.1074/jbc.m114.597831] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mutations in the LARGE gene have been identified in congenital muscular dystrophy (CMD) patients with brain abnormalities. Both LARGE and its paralog, LARGE2 (also referred to as GYLTL1B) are bifunctional glycosyltransferases with xylosyltransferase (Xyl-T) and glucuronyltransferase (GlcA-T) activities, and are capable of forming polymers consisting of [-3Xyl-α1,3GlcAβ1-] repeats. LARGE-dependent modification of α-dystroglycan (α-DG) with these polysaccharides is essential for the ability of α-DG to act as a receptor for ligands in the extracellular matrix. Here we report on the endogenous enzymatic activities of LARGE and LARGE2 in mice and humans, using a newly developed assay for GlcA-T activity. We show that normal mouse and human cultured cells have endogenous LARGE GlcA-T, and that this activity is absent in cells from the Large(myd) (Large-deficient) mouse model of muscular dystrophy, as well as in cells from CMD patients with mutations in the LARGE gene. We also demonstrate that GlcA-T activity is significant in the brain, heart, and skeletal muscle of wild-type and Large2(-/-) mice, but negligible in the corresponding tissues of the Large(myd) mice. Notably, GlcA-T activity is substantial, though reduced, in the kidneys of both the Large(myd) and Large2(-/-) mice, consistent with the observation of α-DG/laminin binding in these contexts. This study is the first to test LARGE activity in samples as small as cryosections and, moreover, provides the first direct evidence that not only LARGE, but also LARGE2, is vital to effective functional modification of α-DG in vivo.
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Affiliation(s)
- Kei-ichiro Inamori
- From the Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology, Department of Internal Medicine, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, Iowa 52242-1101, Division of Glycopathology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Pharmaceutical University, Sendai, Miyagi 981-8558, Japan
| | - Tobias Willer
- From the Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology, Department of Internal Medicine, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, Iowa 52242-1101
| | - Yuji Hara
- From the Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology, Department of Internal Medicine, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, Iowa 52242-1101
| | - David Venzke
- From the Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology, Department of Internal Medicine, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, Iowa 52242-1101
| | - Mary E Anderson
- From the Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology, Department of Internal Medicine, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, Iowa 52242-1101
| | - Nigel F Clarke
- Institute for Neuroscience and Muscle Research, The Children's Hospital at Westmead, University of Sydney, Sydney, Australia
| | - Pascale Guicheney
- Inserm, U1166, Faculté de Médecine Pierre et Marie Curie, Institute of Cardiometabolism and Nutrition, ICAN, Paris, France, Sorbonne Universités, UPMC Univ Paris 06, UMR_S1166, Paris, France
| | - Carsten G Bönnemann
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892
| | - Steven A Moore
- Department of Pathology, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, Iowa 52242
| | - Kevin P Campbell
- From the Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology, Department of Internal Medicine, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, Iowa 52242-1101,
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Novel mutations in the fukutin gene in a boy with asymptomatic hyperCKemia. Neuromuscul Disord 2013; 23:1010-5. [DOI: 10.1016/j.nmd.2013.09.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 09/03/2013] [Accepted: 09/23/2013] [Indexed: 11/17/2022]
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3
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Live D, Wells L, Boons GJ. Dissecting the molecular basis of the role of the O-mannosylation pathway in disease: α-dystroglycan and forms of muscular dystrophy. Chembiochem 2013; 14:2392-402. [PMID: 24318691 DOI: 10.1002/cbic.201300417] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Indexed: 11/10/2022]
Abstract
Dystroglycanopathies form a subgroup of muscular dystrophies that arise from defects in enzymes that are implicated in the recently elucidated O-mannosylation pathway, thereby resulting in underglycosylation of α-dystroglycan. The emerging identification of additional brain proteins modified by O-mannosylation provides a broader context for interpreting the range of neurological consequences associated with dystroglycanopathies. This form of glycosylation is associated with protein mucin-like domains that present numerous serine and threonine residues as possible sites for modification. Furthermore, the O-Man glycans coexist in this region with O-GalNAc glycans (conventionally associated with such protein sequences), thus resulting in a complex glycoconjugate landscape. Sorting out the relationships between the various molecular defects in glycosylation and the modes of disease presentation, as well as the regulatory interplay among the O-Man glycans and the effects on other modes of glycosylation in the same domain, is challenging. Here we provide a perspective on chemical biology approaches employing synthetic and analytical methods to address these questions.
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Affiliation(s)
- David Live
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602 (USA)
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4
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Beedle AM, Turner AJ, Saito Y, Lueck JD, Foltz SJ, Fortunato MJ, Nienaber PM, Campbell KP. Mouse fukutin deletion impairs dystroglycan processing and recapitulates muscular dystrophy. J Clin Invest 2012; 122:3330-42. [PMID: 22922256 DOI: 10.1172/jci63004] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 06/21/2012] [Indexed: 11/17/2022] Open
Abstract
Dystroglycan is a transmembrane glycoprotein that links the extracellular basement membrane to cytoplasmic dystrophin. Disruption of the extensive carbohydrate structure normally present on α-dystroglycan causes an array of congenital and limb girdle muscular dystrophies known as dystroglycanopathies. The essential role of dystroglycan in development has hampered elucidation of the mechanisms underlying dystroglycanopathies. Here, we developed a dystroglycanopathy mouse model using inducible or muscle-specific promoters to conditionally disrupt fukutin (Fktn), a gene required for dystroglycan processing. In conditional Fktn-KO mice, we observed a near absence of functionally glycosylated dystroglycan within 18 days of gene deletion. Twenty-week-old KO mice showed clear dystrophic histopathology and a defect in glycosylation near the dystroglycan O-mannose phosphate, whether onset of Fktn excision driven by muscle-specific promoters occurred at E8 or E17. However, the earlier gene deletion resulted in more severe phenotypes, with a faster onset of damage and weakness, reduced weight and viability, and regenerating fibers of smaller size. The dependence of phenotype severity on the developmental timing of muscle Fktn deletion supports a role for dystroglycan in muscle development or differentiation. Moreover, given that this conditional Fktn-KO mouse allows the generation of tissue- and timing-specific defects in dystroglycan glycosylation, avoids embryonic lethality, and produces a phenotype resembling patient pathology, it is a promising new model for the study of secondary dystroglycanopathy.
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Affiliation(s)
- Aaron M Beedle
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
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5
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Endo T, Manya H, Seta N, Guicheney P. POMGnT1, POMT1, and POMT2 mutations in congenital muscular dystrophies. Methods Enzymol 2010; 479:343-52. [PMID: 20816175 DOI: 10.1016/s0076-6879(10)79019-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Alpha-dystroglycanopathies are a group of rare inherited neuromuscular disorders characterized by reduced glycosylation of alpha-dystroglycan (alpha-DG). Mutations in six genes (POMT1, POMT2, POMGNT1, FKTN, FKRP, and LARGE) have been identified in patients with alpha-dystroglycanopathies. Due to an extremely broad clinical spectrum and relatively poor phenotype-genotype correlation, diagnosis of alpha-dystroglycanopathies is difficult and requires searching for mutations gene by gene. At present, of the six proteins involved on alpha-dystroglycanopathies, the function of the gene products is only known for POMT1, POMT2, and POMGnT1, all responsible for the O-mannosylglycan biosynthesis. This chapter describes the assay protocols to diagnose patients with alpha-dystroglycanopathy by measuring glycosyltransferase activity.
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Affiliation(s)
- Tamao Endo
- Molecular Glycobiology, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan
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6
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Demir E, Gucuyener K, Akturk A, Talim B, Konus O, Del Bo R, Ghezzi S, Comi GP. An unusual presentation of Muscle–Eye–Brain disease: Severe eye abnormalities with mild muscle and brain involvement. Neuromuscul Disord 2009; 19:692-5. [DOI: 10.1016/j.nmd.2009.07.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2009] [Revised: 07/15/2009] [Accepted: 07/20/2009] [Indexed: 10/20/2022]
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7
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Reed UC. Congenital muscular dystrophy. Part I: a review of phenotypical and diagnostic aspects. ARQUIVOS DE NEURO-PSIQUIATRIA 2009; 67:144-68. [DOI: 10.1590/s0004-282x2009000100038] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Accepted: 12/17/2008] [Indexed: 12/30/2022]
Abstract
The congenital muscular dystrophies (CMDs) are a group of genetically and clinically heterogeneous hereditary myopathies with preferentially autosomal recessive inheritance, that are characterized by congenital hypotonia, delayed motor development and early onset of progressive muscle weakness associated with dystrophic pattern on muscle biopsy. The clinical course is broadly variable and can comprise the involvement of the brain and eyes. From 1994, a great development in the knowledge of the molecular basis has occurred and the classification of CMDs has to be continuously up dated. We initially present the main clinical and diagnostic data concerning the CMDs related to changes in the complex dystrophin-associated glycoproteins-extracellular matrix: CMD with merosin deficiency (CMD1A), collagen VI related CMDs (Ullrich CMD and Bethlem myopathy), CMDs with abnormal glycosylation of alpha-dystroglycan (Fukuyama CMD, Muscle-eye-brain disease, Walker-Warburg syndrome, CMD1C, CMD1D), and the much rarer CMD with integrin deficiency. Finally, we present other forms of CMDs not related with the dystrophin/glycoproteins/extracellular matrix complex (rigid spine syndrome, CMD1B, CMD with lamin A/C deficiency), and some apparently specific clinical forms not yet associated with a known molecular mechanism. The second part of this review concerning the pathogenesis and therapeutic perspectives of the different subtypes of CMD will be described in a next number.
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8
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Manya H, Bouchet C, Yanagisawa A, Vuillaumier-Barrot S, Quijano-Roy S, Suzuki Y, Maugenre S, Richard P, Inazu T, Merlini L, Romero NB, Leturcq F, Bezier I, Topaloglu H, Estournet B, Seta N, Endo T, Guicheney P. Protein O-mannosyltransferase activities in lymphoblasts from patients with α-dystroglycanopathies. Neuromuscul Disord 2008; 18:45-51. [PMID: 17869517 DOI: 10.1016/j.nmd.2007.08.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Revised: 07/23/2007] [Accepted: 08/08/2007] [Indexed: 11/19/2022]
Abstract
Defects in O-mannosylation of alpha-dystroglycan cause some forms of congenital muscular dystrophy (CMD), the so-called alpha-dystroglycanopathies. Six genes are responsible for these diseases with overlapping phenotypes. We investigated the usefulness of a biochemical approach for the diagnosis and investigation of the alpha-dystroglycanopathies using immortalized lymphoblasts prepared from genetically diagnosed and undiagnosed CMD patients and from control subjects. We measured the activities of protein O-mannose beta1,2-N-acetylglucosaminyltransferase 1 (POMGnT1) and protein O-mannosyltransferase (POMT). Lymphoblasts from patients harbouring known mutations in either POMGNT1 or POMT1 showed a marked decrease in POMGnT1 or POMT activity, respectively, compared to controls. Furthermore, we identified pathogenic mutations in POMGNT1, POMT1 or POMT2 in six previously genetically uncharacterised patients who had very low enzyme activity. In conclusion, the lymphoblast-based enzymatic assay is a sensitive and useful method (i) to select patients harbouring POMGNT1, POMT1 or POMT2 mutations; (ii) to assess the pathogenicity of new or already described mutations.
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Affiliation(s)
- Hiroshi Manya
- Glycobiology Research Group, Tokyo Metropolitan Institute of Gerontology, Foundation for Research on Aging and Promotion of Human Welfare, Tokyo, Japan
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9
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Hehr U, Uyanik G, Gross C, Walter MC, Bohring A, Cohen M, Oehl-Jaschkowitz B, Bird LM, Shamdeen GM, Bogdahn U, Schuierer G, Topaloglu H, Aigner L, Lochmüller H, Winkler J. Novel POMGnT1 mutations define broader phenotypic spectrum of muscle-eye-brain disease. Neurogenetics 2007; 8:279-88. [PMID: 17906881 DOI: 10.1007/s10048-007-0096-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2007] [Accepted: 07/02/2007] [Indexed: 11/26/2022]
Abstract
Muscle-eye-brain disease (MEB, OMIM 253280) is an autosomal recessive disorder characterized by a distinct triad of congenital muscular dystrophy, structural eye abnormalities, and cobblestone lissencephaly. Clinically, MEB patients present with early onset muscular hypotonia, severely compromised motor development, and mental retardation. Magnetic resonance imaging reveals a lissencephaly type II with hypoplasia of the brainstem and cerebellum. MEB is associated with mutations in the gene for protein O-mannose beta-1,2-N-acetylglucosaminyltransferase (POMGnT1, OMIM 606822). In this paper, we report the clinical findings of nine MEB patients from eight families. Eight of the nine patients presented typical features of MEB. However, a broad phenotypic variability was observed, ranging from two patients with severe autistic features to another patient with an unusually mild phenotype, initially diagnosed as congenital muscular dystrophy. Furthermore, severe hydrocephalus was reported in two families during a previous pregnancy, emphasizing the phenotypic overlap with Walker-Warburg syndrome. In addition to three previously reported mutations, we identified six novel POMGnT1 mutations (one missense, five truncating) in the present patient cohort. Our data suggest mutational hotspots within the minimal catalytic domain at arginine residue 442 (exon 16) and in intron 17. It is interesting to note that all mutations analyzed so far result in a complete loss of enzyme activity. Therefore, we conclude that the type and position of the POMGnT1 mutations are not of predictive value for the clinical severity. This supports the notion that additional environmental and/or genetic factors may contribute to the observed broad spectrum of POMGnT1-associated phenotypes.
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Affiliation(s)
- Ute Hehr
- Center for Human Genetics and Department of Human Genetics, University of Regensburg, Universitätklinikum D3, Franz-Josef-Strauss-Allee 11, Regensburg 93053, Germany.
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10
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Martin PT. Mechanisms of disease: congenital muscular dystrophies-glycosylation takes center stage. ACTA ACUST UNITED AC 2007; 2:222-30. [PMID: 16932553 PMCID: PMC2855642 DOI: 10.1038/ncpneuro0155] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Accepted: 02/10/2006] [Indexed: 11/09/2022]
Abstract
Recent studies have defined a group of muscular dystrophies, now termed the dystroglycanopathies, as novel disorders of glycosylation. These conditions include Walker-Warburg syndrome, muscle-eye-brain disease, Fukuyama-type congenital muscular dystrophy, congenital muscular dystrophy types 1C and 1D, and limb-girdle muscular dystrophy type 2I. Although clinical findings can be highly variable, dystroglycanopathies are all characterized by cortical malformations and ocular defects at the more severe end of the clinical spectrum, in addition to muscular dystrophy. All of these disorders are defined by the underglycosylation of alpha-dystroglycan. Defective glycosylation of dystroglycan severs the link between this important cell adhesion molecule and the extracellular matrix, thereby contributing to cellular pathology. Recent experiments indicate that glycosylation might not only define forms of muscular dystrophy but also provide an avenue to the development of therapies for these disorders.
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Affiliation(s)
- Paul T Martin
- Columbus Children's Research Institute, Departments of Pediatrics and Neurology, Ohio State University, Columbus, OH 43205, USA.
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11
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Bouchet C, Gonzales M, Vuillaumier-Barrot S, Devisme L, Lebizec C, Alanio E, Bazin A, Bessières-Grattagliano B, Bigi N, Blanchet P, Bonneau D, Bonnières M, Carles D, Delahaye S, Fallet-Bianco C, Figarella-Branger D, Gaillard D, Gasser B, Guimiot F, Joubert M, Laurent N, Liprandi A, Loget P, Marcorelles P, Martinovic J, Menez F, Patrier S, Pelluard-Nehmé F, Perez MJ, Rouleau-Dubois C, Triau S, Laquerrière A, Encha-Razavi F, Seta N. Molecular heterogeneity in fetal forms of type II lissencephaly. Hum Mutat 2007; 28:1020-7. [PMID: 17559086 DOI: 10.1002/humu.20561] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Type II lissencephaly (type II LIS) is a group of autosomal recessive congenital muscular dystrophies (CMD) associated with defects in alpha-DG O-glycosylation, which comprises Walker-Warburg syndrome, Fukuyama cerebral and muscular dystrophy, or muscle-eye-brain disease. The most severe forms of these diseases often have a fetal presentation and lead to a pregnancy termination. We report here the first molecular study on fetal type II LIS in a series of 47 fetuses from 41 unrelated families. Sequencing of the different genes known to be involved in alpha-DG O-glycosylation allowed the molecular diagnosis in 22 families: involvement of POMT1 was demonstrated in 32% of cases, whereas POMGNT1 and POMT2 were incriminated in 15% and in 7% of cases, respectively. We found 30 different mutations in these three genes, 25 were described herein for the first time, 15 in POMT1, and five in POMT2 and POMGNT1. Despite sequencing of FKRP, FCMD, and LARGE, no definitive molecular diagnosis could be made for the other half of our cases. Preliminary results concerning genotype-phenotype correlations show that the choice of the first gene sequenced should depend on the clinical severity of the type II LIS; POMT1 and POMT2 for severest clinical picture and POMGNT1 for milder disease. The other genes, FKRP, FCMD, and LARGE, seem not to be implicated in the fetal form of CMD.
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Affiliation(s)
- C Bouchet
- Assistance Publique-Hôpitaux de Paris (APHP), Bichat-Claude Bernard Hospital, Biochimie Métabolique, Paris, France
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12
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Jaiswal JK, Marlow G, Summerill G, Mahjneh I, Mueller S, Hill M, Miyake K, Haase H, Anderson LVB, Richard I, Kiuru-Enari S, McNeil PL, Simon SM, Bashir R. Patients with a non-dysferlin Miyoshi myopathy have a novel membrane repair defect. Traffic 2006; 8:77-88. [PMID: 17132147 DOI: 10.1111/j.1600-0854.2006.00505.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Two autosomal recessive muscle diseases, limb girdle muscular dystrophy type 2B (LGMD2B) and Miyoshi myopathy (MM), are caused by mutations in the dysferlin gene. These mutations result in poor ability to repair cell membrane damage, which is suggested to be the cause for this disease. However, many patients who share clinical features with MM-type muscular dystrophy do not carry mutations in dysferlin gene. To understand the basis of MM that is not due to mutations in dysferlin gene, we analyzed cells from patients in one such family. In these patients, we found no defects in several potential candidates - annexin A2, caveolin-3, myoferlin and the MMD2 locus on chromosome 10p. Similar to dysferlinopathy, these cells also exhibit membrane repair defects and the severity of the defect correlated with severity of their disease. However, unlike dysferlinopathy, none of the conventional membrane repair pathways are defective in these patient cells. These results add to the existing evidence that cell membrane repair defect may be responsible for MM-type muscular dystrophy and indicate that a previously unsuspected genetic lesion that affects cell membrane repair pathway is responsible for the disease in the non-dysferlin MM patients.
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Affiliation(s)
- Jyoti K Jaiswal
- The Rockefeller University, Box 304, 1230 York Avenue, New York, NY 10021, USA.
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Vajsar J. MRI findings in congenital muscular dystrophies associated with brain abnormalities. FUTURE NEUROLOGY 2006. [DOI: 10.2217/14796708.1.6.765] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Magnetic resonance imaging (MRI) has become an important tool in diagnosing complex congenital muscular dystrophies (CMD) with brain abnormalities. Currently, there are two recognized types of CMDs with MRI brain abnormalities, firstly, laminin α2-chain-deficient CMD (MDC1A) with mutations in the LAMA2 gene, and secondly CMDs with hypoglycosylated α-dystroglycan which include Walker–Warburg syndrome (WWS), muscle–eye–brain disease (MEB), Fukuyama CMD (FCMD) and CMD types 1C and 1D (MDC1C and 1D). Brain MRI in MDC1A demonstrates abnormal white matter but rarely other brain abnormalities. In the latter group of CMDs, there is a whole spectrum of abnormalities involving both white and gray matter. The most severe MRI findings are in WWS. Patients with MEB, FCMD and MDC1C and lD also have gray and white matter abnormalities, which, in general, are less severe than those observed in WWS. There may be an overlap in these complex CMDs, both genotypically and in MRI findings.
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Affiliation(s)
- Jiri Vajsar
- The Hospital for Sick Children & University of Toronto, Division of Neurology, 555 University Avenue, Toronto, ON M5G 1X8, Canada
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Lisi MT, Cohn RD. Congenital muscular dystrophies: new aspects of an expanding group of disorders. Biochim Biophys Acta Mol Basis Dis 2006; 1772:159-72. [PMID: 17097859 DOI: 10.1016/j.bbadis.2006.09.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Revised: 09/11/2006] [Accepted: 09/13/2006] [Indexed: 12/24/2022]
Abstract
The congenital muscular dystrophies comprise a genetically and clinically heterogeneous group of disorders characterized by early onset of progressive muscle weakness and often involvement of other organ systems such as the brain and eyes. During the last decade, significant progress has been made to further characterize various forms of congenital muscular dystrophies based on their specific genetic and clinical appearance. This review represents an overview of the recent accomplishments as they relate to clinical, diagnostic, pathogenetic and therapeutic aspects of congenital muscular dystrophies.
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Affiliation(s)
- Matthew T Lisi
- McKusick-Nathans Institute of Genetic Medicine, Department of Pediatrics and Neurology, Johns Hopkins University School of Medicine, 600 N Wolfe Street, Blalock 1008 Baltimore, MD 21287, USA
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Mendell JR, Boué DR, Martin PT. The congenital muscular dystrophies: recent advances and molecular insights. Pediatr Dev Pathol 2006; 9:427-43. [PMID: 17163796 PMCID: PMC2855646 DOI: 10.2350/06-07-0127.1] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2006] [Accepted: 08/30/2006] [Indexed: 01/16/2023]
Abstract
Over the past decade, molecular understanding of the congenital muscular dystrophies (CMDs) has greatly expanded. The diseases can be classified into 3 major groups based on the affected genes and the location of their expressed protein: abnormalities of extracellular matrix proteins (LAMA2, COL6A1, COL6A2, COL6A3), abnormalities of membrane receptors for the extracellular matrix (fukutin, POMGnT1, POMT1, POMT2, FKRP, LARGE, and ITGA7), and abnormal endoplasmic reticulum protein (SEPN1). The diseases begin in the perinatal period or shortly thereafter. A specific diagnosis can be challenging because the muscle pathology is usually not distinctive. Immunostaining of muscle using a battery of antibodies can help define a disorder that will need confirmation by gene testing. In muscle diseases with overlapping pathological features, such as CMD, careful attention to the clinical clues (e.g., family history, central nervous system features) can help guide the battery of immunostains necessary to target an unequivocal diagnosis.
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Affiliation(s)
- Jerry R Mendell
- Department of Pediatrics, Columbus Children's Hospital and Research Institute and The Ohio State University, 700 Children's Drive, Columbus, OH 43205, USA.
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