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G.O.6 Autosomal recessive desminopathy with desmin-null mutations presenting in childhood
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Abstracts / Neuromuscular Disorders 22 (2012) 804–908
patients having no appreciable benefit. Considering the considerable side effects of this therapy, it would be desirable to identify biomarkers able to predict the response to corticosteroids. We have carried out a targeted exon sequencing in 243 genes (identified within the BIO-NMD consortium) which are connected to DMD pathways (identified using the MedScan informatics tools developed by ARIADNE), preceded by a targeted specific enrichment step. For target enrichment Agilent’s SureSelect in solution approach was selected. Sixteen DMD patients (eight high responders and eight low responders) were processed using 5500xl SOLiDe Sequencer. Quality filtering was carried out on the SNP calls returned by LifeScope using quality filters, SNPs in introns were discarded. After quality filtering, 735 SNPs were identified across all samples. We applied two novel statistical methods for analysing variance in the two DMD groups: the multidimensional scaling, and the discriminant analysis, both used to determine which variables discriminate between two (or more) naturally occurring groups. Using both tools we were able to identify 34 SNPs which are differently represented in the two categories (responders/low responders) and do discriminate patients. These SNPs belong to 23 genes, several of which encode for the structural proteins vinculins, integrins, and laminins. In order to validate this data, and to confer robustness and specificity to our identified SNPs, 84 additional DMD patients as well as other non-DMD individuals are now being studied to increase the statistical power of the data. Validated SNPs may represent pharmacogenetic biomarkers for corticosteroid therapy response. http://dx.doi:10.1016/j.nmd.2012.06.235
G.O.5 Deciphering protein aggregates in myofibrillar myopathies – A proteomics approach R.A. Kley 1, A. Maerkens 2, M. Olive 3, K.G. Claeys 4, F. Hanisch 5, P.F.M. van der Ven 6, D.O. Fuerst 6, T. Mueller 2, K. Marcus 2, M. Vorgerd 1 1 University Hospital Bergmannsheil, Ruhr University Bochum, Department of Neurology, Bochum, Germany; 2 Ruhr-University Bochum, Department of Functional Proteomics, Bochum, Germany; 3 IDIBELL-Hospital Universitari de Bellvitge and CIBERNED, Institut de Neuropatologia, Barcelona, Spain; 4 RWTH Aachen University, Institute of Neuropathology, Aachen, Germany; 5 Martin-Luther-University Halle-Wittenberg, Department of Neurology, Halle, Germany; 6 University of Bonn, Institute for Cell Biology, Bonn, Germany Myofibrillar myopathies (MFM) encompass a genetic heterogenous group of muscle disorders characterized by formation of intracellular protein aggregates in skeletal muscle fibers. We applied a proteomic approach to decipher the aggregate composition in MFM subtypes with the aim to identify novel disease-relevant proteins, disease-specific proteomic profiles and new candidates for MFM-causing proteins. Muscle biopsies of 21 genetically clarified MFM patients (filaminopathy, myotilinopathy, desminopathy, ZASPopathy) were analyzed. Aggregates and intraindividual controls (muscle fibers without aggregates) were collected by laser microdissection. A label-free mass spectrometric approach was used for identification and relative quantification of proteins. A total of 588 different proteins were identified. Up to 193 proteins showed an accumulation in protein aggregates in the different MFM subtypes (ratio >1.8 compared to intraindividual controls). Many of these proteins have never been described in the context of MFM so far. A subset of proteins including desmin, filamin C, Xin, Xirp2 and many other proteins was detected in aggregates in all patients. The comparison of MFM subtypes revealed disease-specific patterns of aggregate compositions with clear differences in ratios of most abundant proteins. Filamin C, desmin, myotilin and ZASP showed the highest accumulation in aggregates of related MFM subtypes. Our proteomic data provide essential new insights in the composition of pathological
protein aggregates in MFM. Proteomic profiles of aggregates seem to be specific for the different MFM subtypes and expand our knowledge about proteins involved in pathogenesis of filaminopathy, desminopathy, myotilinopathy and ZASPopathy. The list of abundant proteins in aggregates also include potential new MFM proteins. These should to be considered in future genetic studies in MFM patients with so far unknown mutation. http://dx.doi:10.1016/j.nmd.2012.06.236
G.O.6 Autosomal recessive desminopathy with desmin-null mutations presenting in childhood R. Barresi 1, L. De Waele 2, M. Henderson 1, J. Hudson 1, I. Horrocks 3, C. Longman 3, K. Bushby 1 1 Newcastle upon Tyne NHS Trust, Newcastle upon Tyne, United Kingdom; 2 University of Newcastle, Institute of Genetic Medicine, Newcastle upon Tyne, United Kingdom; 3 Yorkhill Hospitals, Glasgow, United Kingdom Desminopathies are intermediate filament disorders with a mainly dominant autosomal inheritance pattern, characterized by skeletal myopathy and/or cardiomyopathy with average onset in the 3rd decade. The clinical phenotype caused by desmin mutations is described as a myofibrillar myopathy (MFM). This term refers to a group of genetically heterogeneous neuromuscular disorders that share histopathological features of cytoplasmic aggregates of multiple proteins, including desmin, aB-crystallin and myotilin on muscle biopsy. We report on two siblings from healthy, non-consanguineous parents presenting with progressive generalized proximal more than distal muscle weakness in legs and arms from the age of 3 years, facial weakness and ptosis, reduced upward gaze, scapular winging, ankle contractures, mild calf hypertrophy, and swallowing difficulties. No cardiac involvement was detected so far. Creatine kinase levels were raised up to 800 and 1000 IU/L. A muscle MRI of the thigh showed more severe involvement of the posterior compartment with relative sparing of the sartorius and gracilis muscles. Muscle histopathology showed myopathic features with atrophic fibers, nuclear bags, internal nuclei and type 1 fibre predominance with remarkably complete absence of desmin labelling which was confirmed by Western blot. Mutation analysis revealed two compound heterozygous mutations in exon 1 of desmin gene resulting in premature stop codons. This novel clinical phenotype linked to autosomal recessive desminopathy widens the clinical spectrum of this class of disease. http://dx.doi:10.1016/j.nmd.2012.06.237
G.O.7 Distal myopathy with upper limb predominance caused by filamin C haploinsufficiency V. Guergueltcheva 1, K. Peeters 2, J. Baets 3, C. Ceuterick-de Groote 4, J.J. Martin 4, A. Suls 5, E.D. Vriendt 6, V. Mihaylova 1, T. Chamova 1, L. Almeida-Souza 7, E. Ydens 7, C. Tzekov 8, G. Hadjidekov 9, M. Gospodinova 10, K. Storm 11, E. Reyniers 11, S. Bichev 12, P.F.M. van der Ven 13, D.O. Furst 13, V. Mitev 14, H. Lochmuller 15, V. Timmerman 7, I. Tournev 16, P. De Jonghe 5, A. Jordanova 5 1 Medical University-Sofia, Neurology, Sofia, Bulgaria; 2 VIB Department of Molecular Genetics, University of Antwerp, Molecular Neurogenomics Group and Neurogenetics Laboratory, Institute Born-Bunge, Antwerpen, Belgium; 3 VIB Department of Molecular Genetics, University of Antwerp, Neurogenetics Group, Neurogenetics laboratory, Institute Born-Bunge and Division of Neurology, University Hospital Antwerp, Antwerpen, Belgium; 4 Institute Born-Bunge, University of Antwerp, Laboratory of Ultrastructural Neuropathology, Antwerpen, Belgium; 5 University of Antwerp, Neurogenetics Group, VIB Department of Molecular Genet and Neuroge-
Abstracts / Neuromuscular Disorders 22 (2012) 804–908
patients having no appreciable benefit. Considering the considerable side effects of this therapy, it would be desirable to identify biomarkers able to predict the response to corticosteroids. We have carried out a targeted exon sequencing in 243 genes (identified within the BIO-NMD consortium) which are connected to DMD pathways (identified using the MedScan informatics tools developed by ARIADNE), preceded by a targeted specific enrichment step. For target enrichment Agilent’s SureSelect in solution approach was selected. Sixteen DMD patients (eight high responders and eight low responders) were processed using 5500xl SOLiDe Sequencer. Quality filtering was carried out on the SNP calls returned by LifeScope using quality filters, SNPs in introns were discarded. After quality filtering, 735 SNPs were identified across all samples. We applied two novel statistical methods for analysing variance in the two DMD groups: the multidimensional scaling, and the discriminant analysis, both used to determine which variables discriminate between two (or more) naturally occurring groups. Using both tools we were able to identify 34 SNPs which are differently represented in the two categories (responders/low responders) and do discriminate patients. These SNPs belong to 23 genes, several of which encode for the structural proteins vinculins, integrins, and laminins. In order to validate this data, and to confer robustness and specificity to our identified SNPs, 84 additional DMD patients as well as other non-DMD individuals are now being studied to increase the statistical power of the data. Validated SNPs may represent pharmacogenetic biomarkers for corticosteroid therapy response. http://dx.doi:10.1016/j.nmd.2012.06.235
G.O.5 Deciphering protein aggregates in myofibrillar myopathies – A proteomics approach R.A. Kley 1, A. Maerkens 2, M. Olive 3, K.G. Claeys 4, F. Hanisch 5, P.F.M. van der Ven 6, D.O. Fuerst 6, T. Mueller 2, K. Marcus 2, M. Vorgerd 1 1 University Hospital Bergmannsheil, Ruhr University Bochum, Department of Neurology, Bochum, Germany; 2 Ruhr-University Bochum, Department of Functional Proteomics, Bochum, Germany; 3 IDIBELL-Hospital Universitari de Bellvitge and CIBERNED, Institut de Neuropatologia, Barcelona, Spain; 4 RWTH Aachen University, Institute of Neuropathology, Aachen, Germany; 5 Martin-Luther-University Halle-Wittenberg, Department of Neurology, Halle, Germany; 6 University of Bonn, Institute for Cell Biology, Bonn, Germany Myofibrillar myopathies (MFM) encompass a genetic heterogenous group of muscle disorders characterized by formation of intracellular protein aggregates in skeletal muscle fibers. We applied a proteomic approach to decipher the aggregate composition in MFM subtypes with the aim to identify novel disease-relevant proteins, disease-specific proteomic profiles and new candidates for MFM-causing proteins. Muscle biopsies of 21 genetically clarified MFM patients (filaminopathy, myotilinopathy, desminopathy, ZASPopathy) were analyzed. Aggregates and intraindividual controls (muscle fibers without aggregates) were collected by laser microdissection. A label-free mass spectrometric approach was used for identification and relative quantification of proteins. A total of 588 different proteins were identified. Up to 193 proteins showed an accumulation in protein aggregates in the different MFM subtypes (ratio >1.8 compared to intraindividual controls). Many of these proteins have never been described in the context of MFM so far. A subset of proteins including desmin, filamin C, Xin, Xirp2 and many other proteins was detected in aggregates in all patients. The comparison of MFM subtypes revealed disease-specific patterns of aggregate compositions with clear differences in ratios of most abundant proteins. Filamin C, desmin, myotilin and ZASP showed the highest accumulation in aggregates of related MFM subtypes. Our proteomic data provide essential new insights in the composition of pathological
protein aggregates in MFM. Proteomic profiles of aggregates seem to be specific for the different MFM subtypes and expand our knowledge about proteins involved in pathogenesis of filaminopathy, desminopathy, myotilinopathy and ZASPopathy. The list of abundant proteins in aggregates also include potential new MFM proteins. These should to be considered in future genetic studies in MFM patients with so far unknown mutation. http://dx.doi:10.1016/j.nmd.2012.06.236
G.O.6 Autosomal recessive desminopathy with desmin-null mutations presenting in childhood R. Barresi 1, L. De Waele 2, M. Henderson 1, J. Hudson 1, I. Horrocks 3, C. Longman 3, K. Bushby 1 1 Newcastle upon Tyne NHS Trust, Newcastle upon Tyne, United Kingdom; 2 University of Newcastle, Institute of Genetic Medicine, Newcastle upon Tyne, United Kingdom; 3 Yorkhill Hospitals, Glasgow, United Kingdom Desminopathies are intermediate filament disorders with a mainly dominant autosomal inheritance pattern, characterized by skeletal myopathy and/or cardiomyopathy with average onset in the 3rd decade. The clinical phenotype caused by desmin mutations is described as a myofibrillar myopathy (MFM). This term refers to a group of genetically heterogeneous neuromuscular disorders that share histopathological features of cytoplasmic aggregates of multiple proteins, including desmin, aB-crystallin and myotilin on muscle biopsy. We report on two siblings from healthy, non-consanguineous parents presenting with progressive generalized proximal more than distal muscle weakness in legs and arms from the age of 3 years, facial weakness and ptosis, reduced upward gaze, scapular winging, ankle contractures, mild calf hypertrophy, and swallowing difficulties. No cardiac involvement was detected so far. Creatine kinase levels were raised up to 800 and 1000 IU/L. A muscle MRI of the thigh showed more severe involvement of the posterior compartment with relative sparing of the sartorius and gracilis muscles. Muscle histopathology showed myopathic features with atrophic fibers, nuclear bags, internal nuclei and type 1 fibre predominance with remarkably complete absence of desmin labelling which was confirmed by Western blot. Mutation analysis revealed two compound heterozygous mutations in exon 1 of desmin gene resulting in premature stop codons. This novel clinical phenotype linked to autosomal recessive desminopathy widens the clinical spectrum of this class of disease. http://dx.doi:10.1016/j.nmd.2012.06.237
G.O.7 Distal myopathy with upper limb predominance caused by filamin C haploinsufficiency V. Guergueltcheva 1, K. Peeters 2, J. Baets 3, C. Ceuterick-de Groote 4, J.J. Martin 4, A. Suls 5, E.D. Vriendt 6, V. Mihaylova 1, T. Chamova 1, L. Almeida-Souza 7, E. Ydens 7, C. Tzekov 8, G. Hadjidekov 9, M. Gospodinova 10, K. Storm 11, E. Reyniers 11, S. Bichev 12, P.F.M. van der Ven 13, D.O. Furst 13, V. Mitev 14, H. Lochmuller 15, V. Timmerman 7, I. Tournev 16, P. De Jonghe 5, A. Jordanova 5 1 Medical University-Sofia, Neurology, Sofia, Bulgaria; 2 VIB Department of Molecular Genetics, University of Antwerp, Molecular Neurogenomics Group and Neurogenetics Laboratory, Institute Born-Bunge, Antwerpen, Belgium; 3 VIB Department of Molecular Genetics, University of Antwerp, Neurogenetics Group, Neurogenetics laboratory, Institute Born-Bunge and Division of Neurology, University Hospital Antwerp, Antwerpen, Belgium; 4 Institute Born-Bunge, University of Antwerp, Laboratory of Ultrastructural Neuropathology, Antwerpen, Belgium; 5 University of Antwerp, Neurogenetics Group, VIB Department of Molecular Genet and Neuroge-