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Tarrasó Urios Guillermo - One of the best experts on this subject based on the ideXlab platform.
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Modelos celulares de la enfermedad de McArdle : evaluación de la terapia farmacológica con agentes read-through, características del metabolismo energético y de la vía de la autofagia
2020Co-Authors: Tarrasó Urios GuillermoAbstract:La malaltia de McArdle o glucogenosi tipus V es una malaltia del metabolisme del glucogen causada per mutacions patogèniques en ambdues copies del gen PYGM, que codifica per a la isoforma muscular del enzim glucogen fosforilasa (GP-M o miofosforilasa). Este dèficit provoca la incapacitat para degradar el glucogen en el múscul i els pacients presenten com a tret fenotípic principal la intolerància al exercici, podent arribar a rabdomiòlisis. Actualment no existeix cap tractament efectiu per a la malaltia de McArdle. La mutació mes comú entre els pacients es la p.R50X que provoca a un codó de terminació prematur (PTC). Els agents read-through (RTAs) son petites molècules que tenen la capacitat de induir un efecte read-through sobre un PTC, produint la lectura completa de la proteïna. Per aquest motiu, en el present treball s'avalua la hipòtesis de que el tractament farmacològic amb RTAs pot restablir el mínim de proteïna GP-M per a la millora del fenotip en els pacients de McArdle. Amb aquest objectiu s'han estudiat els compostos G418, Ataluren, Amlexanox y RTC13 en dos models cel·lulars de la malaltia de McArdle: cultius de cèl·lules HeLa transfectades amb plàsmids que contenen el PTC p.R50X y cultius de cèl·lules provinents de músculs del model murí de la malaltia de McArdle. Els RTAs avaluats no han aconseguit produir un efecte read-through en els models utilitzats. Per altra banda, en el present treball també es planteja la hipòtesis de que la incapacitat de utilitzar el glucogen com font d'energia en els pacients de McArdle produeix canvis metabòlics adaptatius. Esta hipòtesis s'ha avaluat en dos sistemes, músculs de ratolins del model de McArdle y cultius cel·lulars procedents del mateix. A través d'estudis dels paràmetres bioquímics en els medis de cultiu i anàlisis proteics d'enzims implicats en les vies metabòliques de ambdós models, s'han observat alteracions en el metabolisme de les vies energètiques i en la via degradativa de la autofàgia. S'ha comprovat que estes alteracions varien en funció dels subministres energètics del medi (glucosa, àcid palmític y dejú). La via de la autofàgia suposa un sistema alternatiu a la degradació citoplasmàtica de glucogen mitjançant la degradació lisosomal, amb la qual cosa la modulació de esta via podria ser una nova via per a la millora del fenotip dels pacients McArdle.La enfermedad de McArdle o glucogenosis tipo V es una enfermedad del metabolismo del glucógeno causada por mutaciones patogénicas en ambas copias del gen PYGM, que codifica para la isoforma muscular de la enzima glucógeno fosforilasa (GP-M o miofosforilasa). Este déficit conduce a la incapacidad para degradar el glucógeno en el músculo y los pacientes presentan como rasgo fenotípico principal la intolerancia al ejercicio, pudiendo llegar a rabdomiolisis. Actualmente no existe ningún tratamiento efectivo para la enfermedad de McArdle. La mutación más común entre los pacientes es la p.R50X que conduce a un codón de terminación prematuro (PTC). Los agentes read-through (RTAs) son pequeñas moléculas que tienen la capacidad de inducir un efecto read-through sobre un PTC, produciendo la lectura completa de la proteína. Por este motivo en el presente trabajo se evalúa la hipótesis de que el tratamiento farmacológico con RTAs puede reestablecer el mínimo de proteína GP-M para la mejora del fenotipo en los pacientes de McArdle. Para ello se han estudiado los compuestos G418, Ataluren, Amlexanox y RTC13 en dos modelos celulares de la enfermedad de McArdle: cultivos de células HeLa transfectadas con plásmidos que contienen el PTC p.R50X y cultivos de células provenientes de músculos del modelo murino de la enfermedad de McArdle. Los RTAs evaluados no han conseguido producir un efecto read-through en los modelos utilizados. Por otra parte, en el presente trabajo también se plantea la hipótesis de que la incapacidad de utilizar el glucógeno como fuente de energía en los pacientes de McArdle produce cambios metabólicos adaptativos. Esta hipótesis se ha evaluado en dos sistemas, músculos de ratones del modelo de McArdle y cultivos celulares procedentes del mismo. A través de estudios de los parámetros bioquímicos en los medios de cultivo y análisis proteicos de enzimas implicadas en las vías metabólicas de ambos modelos, se han observado alteraciones en el metabolismo de las vías energéticas y en la vía degradativa de la autofagia. Se ha comprobado que estas alteraciones varían en función de los aportes energéticos del medio (glucosa, ácido palmítico y ayuno). La vía de la autofagia supone un sistema alternativo a la degradación citoplasmática de glucógeno por medio de degradación lisosomal, por lo que la modulación de esta vía podría ser una nueva vía para la mejoría del fenotipo de los pacientes McArdle.McArdle disease or GSD type V is a glycogen metabolism disease caused by mutation in both copies of PYGM gene, which codifies for the muscular isoform of glycogen phosphorylase (GP-M or myophosphorilase). The patients are unable to use glycogen as energy source, and as a consequence they experience exercise intolerance, that can lead to rhabdomyolysis. Nowadays there is no effective therapy for the McArdle disease. Most prevalent mutation in McArdle's patients is p.R50X, which produces a Premature Termination Codon (PTC). Read-through agents (RTAs) are small molecules with the capacity to induce a read-through effect on a PTC, producing full-length protein synthesis. For this reason, in the present work the hypothesis that the pharmacological treatment with RTAs can restore a minimum amount of protein to improve the phenotype of the patients is evaluated. In order to do this we have tested the G418, Ataluren, Amlexanox and RTC13 compounds in two cellular models of McArdle disease: cultured HeLa cells transfected with a plasmid containing the p.R50X PTC and cultured muscular cells from the McArdle mouse model. The RTAs tested were unable to produce a read-through effect in both cellular models. Furthermore, it is also evaluated the hypothesis that the incapability of using glycogen as an energy source produces adaptative metabolic changes. This hypothesis has been tested in two different systems: in the skeletal muscle from the McArdle mouse model and in skeletal muscle cultures derived from the same model. Through biochemical values and protein analysis of metabolic pathways related enzymes of both models, we have observed alterations in energetic metabolic pathways and the degradative pathway of autophagy. It is verified that these alterations may vary depending on the medium composition in energetic compounds (glucose, palmitic acid, fasting). Autophagy pathway is an alternative system of glycogen cytoplasmic degradation in lysosomal organelles, so the modulation of this pathway may be a new opportunity for the phenotype improvement of the McArdle patients
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Modelos celulares de la enfermedad de McArdle: evaluación de la terapia farmacológica con agentes read-through, características del metabolismo energético y de la vía de la autofagia
'Universitat Autonoma de Barcelona', 2020Co-Authors: Tarrasó Urios GuillermoAbstract:La malaltia de McArdle o glucogenosi tipus V es una malaltia del metabolisme del glucogen causada per mutacions patogèniques en ambdues copies del gen PYGM, que codifica per a la isoforma muscular del enzim glucogen fosforilasa (GP-M o miofosforilasa). Este dèficit provoca la incapacitat para degradar el glucogen en el múscul i els pacients presenten com a tret fenotípic principal la intolerància al exercici, podent arribar a rabdomiòlisis. Actualment no existeix cap tractament efectiu per a la malaltia de McArdle. La mutació mes comú entre els pacients es la p.R50X que provoca a un codó de terminació prematur (PTC). Els agents read-through (RTAs) son petites molècules que tenen la capacitat de induir un efecte read-through sobre un PTC, produint la lectura completa de la proteïna. Per aquest motiu, en el present treball s’avalua la hipòtesis de que el tractament farmacològic amb RTAs pot restablir el mínim de proteïna GP-M per a la millora del fenotip en els pacients de McArdle. Amb aquest objectiu s’han estudiat els compostos G418, Ataluren, Amlexanox y RTC13 en dos models cel·lulars de la malaltia de McArdle: cultius de cèl·lules HeLa transfectades amb plàsmids que contenen el PTC p.R50X y cultius de cèl·lules provinents de músculs del model murí de la malaltia de McArdle. Els RTAs avaluats no han aconseguit produir un efecte read-through en els models utilitzats. Per altra banda, en el present treball també es planteja la hipòtesis de que la incapacitat de utilitzar el glucogen com font d’energia en els pacients de McArdle produeix canvis metabòlics adaptatius. Esta hipòtesis s’ha avaluat en dos sistemes, músculs de ratolins del model de McArdle y cultius cel·lulars procedents del mateix. A través d’estudis dels paràmetres bioquímics en els medis de cultiu i anàlisis proteics d’enzims implicats en les vies metabòliques de ambdós models, s’han observat alteracions en el metabolisme de les vies energètiques i en la via degradativa de la autofàgia. S’ha comprovat que estes alteracions varien en funció dels subministres energètics del medi (glucosa, àcid palmític y dejú). La via de la autofàgia suposa un sistema alternatiu a la degradació citoplasmàtica de glucogen mitjançant la degradació lisosomal, amb la qual cosa la modulació de esta via podria ser una nova via per a la millora del fenotip dels pacients McArdle.La enfermedad de McArdle o glucogenosis tipo V es una enfermedad del metabolismo del glucógeno causada por mutaciones patogénicas en ambas copias del gen PYGM, que codifica para la isoforma muscular de la enzima glucógeno fosforilasa (GP-M o miofosforilasa). Este déficit conduce a la incapacidad para degradar el glucógeno en el músculo y los pacientes presentan como rasgo fenotípico principal la intolerancia al ejercicio, pudiendo llegar a rabdomiolisis. Actualmente no existe ningún tratamiento efectivo para la enfermedad de McArdle. La mutación más común entre los pacientes es la p.R50X que conduce a un codón de terminación prematuro (PTC). Los agentes read-through (RTAs) son pequeñas moléculas que tienen la capacidad de inducir un efecto read-through sobre un PTC, produciendo la lectura completa de la proteína. Por este motivo en el presente trabajo se evalúa la hipótesis de que el tratamiento farmacológico con RTAs puede reestablecer el mínimo de proteína GP-M para la mejora del fenotipo en los pacientes de McArdle. Para ello se han estudiado los compuestos G418, Ataluren, Amlexanox y RTC13 en dos modelos celulares de la enfermedad de McArdle: cultivos de células HeLa transfectadas con plásmidos que contienen el PTC p.R50X y cultivos de células provenientes de músculos del modelo murino de la enfermedad de McArdle. Los RTAs evaluados no han conseguido producir un efecto read-through en los modelos utilizados. Por otra parte, en el presente trabajo también se plantea la hipótesis de que la incapacidad de utilizar el glucógeno como fuente de energía en los pacientes de McArdle produce cambios metabólicos adaptativos. Esta hipótesis se ha evaluado en dos sistemas, músculos de ratones del modelo de McArdle y cultivos celulares procedentes del mismo. A través de estudios de los parámetros bioquímicos en los medios de cultivo y análisis proteicos de enzimas implicadas en las vías metabólicas de ambos modelos, se han observado alteraciones en el metabolismo de las vías energéticas y en la vía degradativa de la autofagia. Se ha comprobado que estas alteraciones varían en función de los aportes energéticos del medio (glucosa, ácido palmítico y ayuno). La vía de la autofagia supone un sistema alternativo a la degradación citoplasmática de glucógeno por medio de degradación lisosomal, por lo que la modulación de esta vía podría ser una nueva vía para la mejoría del fenotipo de los pacientes McArdle.McArdle disease or GSD type V is a glycogen metabolism disease caused by mutation in both copies of PYGM gene, which codifies for the muscular isoform of glycogen phosphorylase (GP-M or myophosphorilase). The patients are unable to use glycogen as energy source, and as a consequence they experience exercise intolerance, that can lead to rhabdomyolysis. Nowadays there is no effective therapy for the McArdle disease. Most prevalent mutation in McArdle’s patients is p.R50X, which produces a Premature Termination Codon (PTC). Read-through agents (RTAs) are small molecules with the capacity to induce a read-through effect on a PTC, producing full-length protein synthesis. For this reason, in the present work the hypothesis that the pharmacological treatment with RTAs can restore a minimum amount of protein to improve the phenotype of the patients is evaluated. In order to do this we have tested the G418, Ataluren, Amlexanox and RTC13 compounds in two cellular models of McArdle disease: cultured HeLa cells transfected with a plasmid containing the p.R50X PTC and cultured muscular cells from the McArdle mouse model. The RTAs tested were unable to produce a read-through effect in both cellular models. Furthermore, it is also evaluated the hypothesis that the incapability of using glycogen as an energy source produces adaptative metabolic changes. This hypothesis has been tested in two different systems: in the skeletal muscle from the McArdle mouse model and in skeletal muscle cultures derived from the same model. Through biochemical values and protein analysis of metabolic pathways related enzymes of both models, we have observed alterations in energetic metabolic pathways and the degradative pathway of autophagy. It is verified that these alterations may vary depending on the medium composition in energetic compounds (glucose, palmitic acid, fasting). Autophagy pathway is an alternative system of glycogen cytoplasmic degradation in lysosomal organelles, so the modulation of this pathway may be a new opportunity for the phenotype improvement of the McArdle patients.Universitat Autònoma de Barcelona. Programa de Doctorat en Medicin
Miguel A Martin - One of the best experts on this subject based on the ideXlab platform.
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muscle molecular adaptations to endurance exercise training are conditioned by glycogen availability a proteomics based analysis in the mcardle mouse model
The Journal of Physiology, 2018Co-Authors: Carmen Fiuzaluces, Gisela Nogalesgadea, Joaquin Arenas, Alejandro Santoslozano, Francisco Llavero, Rocio Campo, Jorge Diezbermejo, Carlos Baladron, Africa Gonzalezmurillo, Miguel A MartinAbstract:KEY POINTS Although they are unable to utilize muscle glycogen, McArdle mice adapt favourably to an individualized moderate-intensity endurance exercise training regime. Yet, they fail to reach the performance capacity of healthy mice with normal glycogen availability. There is a remarkable difference in the protein networks involved in muscle tissue adaptations to endurance exercise training in mice with and without glycogen availability. Indeed, endurance exercise training promoted the expression of only three proteins common to both McArdle and wild-type mice: LIMCH1, PARP1 and TIGD4. In turn, trained McArdle mice presented strong expression of mitogen-activated protein kinase 12 (MAPK12). ABSTRACT McArdle's disease is an inborn disorder of skeletal muscle glycogen metabolism that results in blockade of glycogen breakdown due to mutations in the Myophosphorylase gene. We recently developed a mouse model carrying the homozygous p.R50X common human mutation (McArdle mouse), facilitating the study of how glycogen availability affects muscle molecular adaptations to endurance exercise training. Using quantitative differential analysis by liquid chromatography with tandem mass spectrometry, we analysed the quadriceps muscle proteome of 16-week-old McArdle (n = 5) and wild-type (WT) (n = 4) mice previously subjected to 8 weeks' moderate-intensity treadmill training or to an equivalent control (no training) period. Protein networks enriched within the differentially expressed proteins with training in WT and McArdle mice were assessed by hypergeometric enrichment analysis. Whereas endurance exercise training improved the estimated maximal aerobic capacity of both WT and McArdle mice as compared with controls, it was ∼50% lower than normal in McArdle mice before and after training. We found a remarkable difference in the protein networks involved in muscle tissue adaptations induced by endurance exercise training with and without glycogen availability, and training induced the expression of only three proteins common to McArdle and WT mice: LIM and calponin homology domains-containing protein 1 (LIMCH1), poly (ADP-ribose) polymerase 1 (PARP1 - although the training effect was more marked in McArdle mice), and tigger transposable element derived 4 (TIGD4). Trained McArdle mice presented strong expression of mitogen-activated protein kinase 12 (MAPK12). Through an in-depth proteomic analysis, we provide mechanistic insight into how glycogen availability affects muscle protein signalling adaptations to endurance exercise training.
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The ‘McArdle paradox’: exercise is a good advice for the exercise intolerant
2016Co-Authors: Ro Lucia, Miguel A Martin, Ros Quinlivan, Andrew Wakelin, Antoni L AndreuAbstract:type V, OMIM database number 232600) may provide the ultimate model of exer-cise intolerance in humans, and thus is of great interest in the sports medicine setting. The condition is an autosomal recessive disorder of muscle glycogen metabolism originally described in 1951 by Brian McArdle.1 Patients have patho-genic mutations in both alleles of the PYGM gene, which encodes myopho-sphorylase, the skeletal muscle isoform of glycogen phosphorylase.2 As a result, Myophosphorylase activity is totally absent. Because this enzyme initiates the breakdown of muscle glycogen leading to liberation of glucose-1-phosphate, patients are unable to obtain energy from their muscle glycogen stores. Hence this disease is arguably the paradigm of exercise intolerance in humans.2 Exercise is the trigger for symptom occurrence in McArdle patients; as such, they tend to be averse to exercise and have often been advised by clinicians to refrain from exercise. MCARDLE DISEASE AND EXERCISE Men and women are equally affected and symptoms usually begin during childhood, typically in the school playground or physical education classes.3 The clinical presentation is dominated by exercise intolerance in the form of acute crises of early fatigue and contractures, which are often accompanied by exertional rhabdo-myolysis, as indicated by marked increases in serum levels of creatine kinase (CK) activity and myoglobinuria.3 Rhabdomyolysis can sometimes be so severe as to cause acute renal failure. A typical feature of the disease is the so-called ‘second wind ’ phenomenon, that is, marked improvement in the tolerance of aerobic, dynamic, large muscle mass exercise (walking or cycling) after ∼ 10 min.4 Owing to blocked glycogenolysis, exercise intolerance is most marked during activities relying on anaerobic gly-colysis for ATP production, that is, typic-ally isometric exercise (handgrip exercise, carrying weights), but also dynamic exer-cise of high intensity (climbing stairs, sprinting to catch a bus).2,5 Another main characteristic of the disease is a high base-line serum level of CK activity even in the absence of heavy exercise in the previous few hours or days, which would theoretically reflect an ongoing state o
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genes and exercise intolerance insights from mcardle disease
Physiological Genomics, 2016Co-Authors: Gisela Nogalesgadea, Richard Godfrey, Alfredo Santalla, Jaume Collcanti, Guillem Pintosmorell, Tomas Pinos, Joaquin Arenas, Miguel A Martin, Alejandro LuciaAbstract:McArdle disease (glycogen storage disease type V) is caused by inherited deficiency of a key enzyme in muscle metabolism, the skeletal muscle-specific isoform of glycogen phosphorylase, "Myophosphorylase," which is encoded by the PYGM gene. Here we review the main pathophysiological, genotypic, and phenotypic features of McArdle disease and their interactions. To date, moderate-intensity exercise (together with pre-exercise carbohydrate ingestion) is the only treatment option that has proven useful for these patients. Furthermore, regular physical activity attenuates the clinical severity of McArdle disease. This is quite remarkable for a monogenic disorder that consistently leads to the same metabolic defect at the muscle tissue level, that is, complete inability to use muscle glycogen stores. Further knowledge of this disorder would help patients and enhance understanding of exercise metabolism as well as exercise genomics. Indeed, McArdle disease is a paradigm of human exercise intolerance and PYGM genotyping should be included in the genetic analyses that might be applied in the coming personalized exercise medicine as well as in future research on genetics and exercise-related phenotypes.
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Schematic representation of the main findings and conclusions (in grey squares) of our study with regard to the pathophysiology of McArdle disease.
2012Co-Authors: Gisela Nogales-gadea, Joaquin Arenas, Alejandro Lucia, Juan C Rubio, Inés Consuegra-garcía, Marc Cuadros, Yolanda Camara, Javier Torres-torronteras, Carmen Fiuza-luces, Miguel A MartinAbstract:Abbreviations: GS (glycogen synthase), GP [glycogen phosphorylase, muscle isoform (Myophosphorylase)], SERCA1 (sarcoplasmic reticulum Ca2+-ATPase 1).
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a proposed molecular diagnostic flowchart for Myophosphorylase deficiency mcardle disease in blood samples from spanish patients
Human Mutation, 2007Co-Authors: Juan C Rubio, Gisela Nogalesgadea, Joaquin Arenas, Alejandro Lucia, Ines Garciaconsuegra, Alberto Blazquez, A Cabello, Antoni L Andreu, Miguel A MartinAbstract:McArdle disease is a metabolic myopathy due to molecular defects in the Myophosphorylase gene (PYGM), usually diagnosed in muscle biopsy. The aims of this study were to characterize genetically a large series of patients and to establish a protocol of molecular diagnosis on blood samples. We studied 55 Spanish unrelated patients with McArdle disease. Screening for the three more frequent mutations in the PYGM gene in the Spanish population (c.148C>T, p.R50X; c.613G>A, p.G205S; and c.2392T>C, p.W798R) were performed with polymerase chain-reaction and restriction fragment length polymorphism (PCR-RFLP) methods. To identify other mutant alleles, the coding region of PYGM gene was sequenced. The p.R50X mutation was observed in 38 patients, the p.G205S substitution in eight, and the p.W798R change in nine. Nine novel mutations, five missense (c.247A>T, p.I83F; c.521G>A, p.G174D; c.1094C>T, p.A365V; c.1468C>T, p.R490W; and c.1730A>G, p.Q577R), one nonsense mutation (c.2352C>A, p.C784X), three frameshift (c.402del, p.N134KfsX161; c.212_218dup, p.Q73HfsX7; c.1470dup, p.R491AfsX7), and nine previously reported mutations were found. In addition, we also updated the molecular data of 95 unrelated patients with McArdle disease studied thus far in our center. Of these patients, 56 were either homozygous or compound heterozygous for the p.R50X, p.G205S, or p.W798R mutation. By including in the molecular diagnosis protocol sequencing of the exons 1, 14, 17 and 18 of the PYGM gene, 16 further patients were characterized, and therefore we were able to detect the molecular defect in 72 out of 95 patients. A proposed molecular diagnosis protocol of the disease based on blood DNA would avoid muscle biopsy in 75.8% [95% confidence interval (95% CI): 62.1%-78.6%] of patients with McArdle disease.
Joaquin Arenas - One of the best experts on this subject based on the ideXlab platform.
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muscle molecular adaptations to endurance exercise training are conditioned by glycogen availability a proteomics based analysis in the mcardle mouse model
The Journal of Physiology, 2018Co-Authors: Carmen Fiuzaluces, Gisela Nogalesgadea, Joaquin Arenas, Alejandro Santoslozano, Francisco Llavero, Rocio Campo, Jorge Diezbermejo, Carlos Baladron, Africa Gonzalezmurillo, Miguel A MartinAbstract:KEY POINTS Although they are unable to utilize muscle glycogen, McArdle mice adapt favourably to an individualized moderate-intensity endurance exercise training regime. Yet, they fail to reach the performance capacity of healthy mice with normal glycogen availability. There is a remarkable difference in the protein networks involved in muscle tissue adaptations to endurance exercise training in mice with and without glycogen availability. Indeed, endurance exercise training promoted the expression of only three proteins common to both McArdle and wild-type mice: LIMCH1, PARP1 and TIGD4. In turn, trained McArdle mice presented strong expression of mitogen-activated protein kinase 12 (MAPK12). ABSTRACT McArdle's disease is an inborn disorder of skeletal muscle glycogen metabolism that results in blockade of glycogen breakdown due to mutations in the Myophosphorylase gene. We recently developed a mouse model carrying the homozygous p.R50X common human mutation (McArdle mouse), facilitating the study of how glycogen availability affects muscle molecular adaptations to endurance exercise training. Using quantitative differential analysis by liquid chromatography with tandem mass spectrometry, we analysed the quadriceps muscle proteome of 16-week-old McArdle (n = 5) and wild-type (WT) (n = 4) mice previously subjected to 8 weeks' moderate-intensity treadmill training or to an equivalent control (no training) period. Protein networks enriched within the differentially expressed proteins with training in WT and McArdle mice were assessed by hypergeometric enrichment analysis. Whereas endurance exercise training improved the estimated maximal aerobic capacity of both WT and McArdle mice as compared with controls, it was ∼50% lower than normal in McArdle mice before and after training. We found a remarkable difference in the protein networks involved in muscle tissue adaptations induced by endurance exercise training with and without glycogen availability, and training induced the expression of only three proteins common to McArdle and WT mice: LIM and calponin homology domains-containing protein 1 (LIMCH1), poly (ADP-ribose) polymerase 1 (PARP1 - although the training effect was more marked in McArdle mice), and tigger transposable element derived 4 (TIGD4). Trained McArdle mice presented strong expression of mitogen-activated protein kinase 12 (MAPK12). Through an in-depth proteomic analysis, we provide mechanistic insight into how glycogen availability affects muscle protein signalling adaptations to endurance exercise training.
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genes and exercise intolerance insights from mcardle disease
Physiological Genomics, 2016Co-Authors: Gisela Nogalesgadea, Richard Godfrey, Alfredo Santalla, Jaume Collcanti, Guillem Pintosmorell, Tomas Pinos, Joaquin Arenas, Miguel A Martin, Alejandro LuciaAbstract:McArdle disease (glycogen storage disease type V) is caused by inherited deficiency of a key enzyme in muscle metabolism, the skeletal muscle-specific isoform of glycogen phosphorylase, "Myophosphorylase," which is encoded by the PYGM gene. Here we review the main pathophysiological, genotypic, and phenotypic features of McArdle disease and their interactions. To date, moderate-intensity exercise (together with pre-exercise carbohydrate ingestion) is the only treatment option that has proven useful for these patients. Furthermore, regular physical activity attenuates the clinical severity of McArdle disease. This is quite remarkable for a monogenic disorder that consistently leads to the same metabolic defect at the muscle tissue level, that is, complete inability to use muscle glycogen stores. Further knowledge of this disorder would help patients and enhance understanding of exercise metabolism as well as exercise genomics. Indeed, McArdle disease is a paradigm of human exercise intolerance and PYGM genotyping should be included in the genetic analyses that might be applied in the coming personalized exercise medicine as well as in future research on genetics and exercise-related phenotypes.
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Schematic representation of the main findings and conclusions (in grey squares) of our study with regard to the pathophysiology of McArdle disease.
2012Co-Authors: Gisela Nogales-gadea, Joaquin Arenas, Alejandro Lucia, Juan C Rubio, Inés Consuegra-garcía, Marc Cuadros, Yolanda Camara, Javier Torres-torronteras, Carmen Fiuza-luces, Miguel A MartinAbstract:Abbreviations: GS (glycogen synthase), GP [glycogen phosphorylase, muscle isoform (Myophosphorylase)], SERCA1 (sarcoplasmic reticulum Ca2+-ATPase 1).
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a proposed molecular diagnostic flowchart for Myophosphorylase deficiency mcardle disease in blood samples from spanish patients
Human Mutation, 2007Co-Authors: Juan C Rubio, Gisela Nogalesgadea, Joaquin Arenas, Alejandro Lucia, Ines Garciaconsuegra, Alberto Blazquez, A Cabello, Antoni L Andreu, Miguel A MartinAbstract:McArdle disease is a metabolic myopathy due to molecular defects in the Myophosphorylase gene (PYGM), usually diagnosed in muscle biopsy. The aims of this study were to characterize genetically a large series of patients and to establish a protocol of molecular diagnosis on blood samples. We studied 55 Spanish unrelated patients with McArdle disease. Screening for the three more frequent mutations in the PYGM gene in the Spanish population (c.148C>T, p.R50X; c.613G>A, p.G205S; and c.2392T>C, p.W798R) were performed with polymerase chain-reaction and restriction fragment length polymorphism (PCR-RFLP) methods. To identify other mutant alleles, the coding region of PYGM gene was sequenced. The p.R50X mutation was observed in 38 patients, the p.G205S substitution in eight, and the p.W798R change in nine. Nine novel mutations, five missense (c.247A>T, p.I83F; c.521G>A, p.G174D; c.1094C>T, p.A365V; c.1468C>T, p.R490W; and c.1730A>G, p.Q577R), one nonsense mutation (c.2352C>A, p.C784X), three frameshift (c.402del, p.N134KfsX161; c.212_218dup, p.Q73HfsX7; c.1470dup, p.R491AfsX7), and nine previously reported mutations were found. In addition, we also updated the molecular data of 95 unrelated patients with McArdle disease studied thus far in our center. Of these patients, 56 were either homozygous or compound heterozygous for the p.R50X, p.G205S, or p.W798R mutation. By including in the molecular diagnosis protocol sequencing of the exons 1, 14, 17 and 18 of the PYGM gene, 16 further patients were characterized, and therefore we were able to detect the molecular defect in 72 out of 95 patients. A proposed molecular diagnosis protocol of the disease based on blood DNA would avoid muscle biopsy in 75.8% [95% confidence interval (95% CI): 62.1%-78.6%] of patients with McArdle disease.
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splicing mosaic of the Myophosphorylase gene due to a silent mutation in mcardle disease
Neurology, 2003Co-Authors: Israel Fernandezcadenas, Juan C Rubio, A L Andreu, Josep Gamez, Ricardo Gonzalo, M A Martin, Joaquin ArenasAbstract:The authors report the molecular findings in a patient with McArdle disease who harbored a silent polymorphism (K608K) in the Myophosphorylase gene. cDNA studies demonstrated that this polymorphism leads to a severe mosaic alteration in mRNA splicing, including exon skipping, activation of cryptic splice-sites, and exon-intron reorganizations. These findings suggest that, in patients with McArdle disease in whom no pathogenic mutation has been found, any a priori silent polymorphism should be re-evaluated as a putative splicing mutation.
G H Cardinet - One of the best experts on this subject based on the ideXlab platform.
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Myophosphorylase deficiency associated with rhabdomyolysis and exercise intolerance in 6 related charolais cattle
Muscle & Nerve, 1995Co-Authors: S Angelos, Stephanie J Valberg, Sara Shanske, Salvatore Dimauro, Bradford Smith, P S Mcquarrie, S Tsujino, G H CardinetAbstract:A Charolais calf presented to the Veterinary Medical Teaching Hospital with a history of recumbency following forced exercise. The calf was unable to stand, and had severe rhabdomyolysis, dehydration, and electrolyte imbalance. Blood selenium concentrations were within normal limits. A complete absence of histochemical staining for phosphorylase was apparent in muscle biopsies. Five other animals in the herd also had exercise intolerance and had a complete absence of phosphorylase staining in muscle biopsies. Biochemical analyses confirmed a deficiency of Myophosphorylase (range 0-0.3 μmol/g per minute : normals 15-27) with normal to slightly elevated muscle glycogen concentrations. Pedigrees from all affected animals showed a common ancestor on the sire's and dam's side of each phosphorylase-deficient animal, suggesting an autosomal recessive transmission. Although Myophosphorylase deficiency was described in humans (McArdle's disease) over 40 years ago, these cattle represent the first animal model for this disease. © 1995 John Wiley & Sons, Inc.
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Myophosphorylase deficiency associated with rhabdomyolysis and exercise intolerance in 6 related charolais cattle
Muscle & Nerve, 1995Co-Authors: S Angelos, Stephanie J Valberg, Sara Shanske, Salvatore Dimauro, Bradford Smith, P S Mcquarrie, S Tsujino, G H CardinetAbstract:A Charolais calf presented to the Veterinary Medical Teaching Hospital with a history of recumbency following forced exercise. The calf was unable to stand, and had severe rhabdomyolysis, dehydration, and electrolyte imbalance. Blood selenium concentrations were within normal limits. A complete absence of histochemical staining for phosphorylase was apparent in muscle biopsies. Five other animals in the herd also had exercise intolerance and had a complete absence of phosphorylase staining in muscle biopsies. Biochemical analyses confirmed a deficiency of Myophosphorylase (range 0-0.3 mumol/g per minute: normals 15-27) with normal to slightly elevated muscle glycogen concentrations. Pedigrees from all affected animals showed a common ancestor on the sire's and dam's side of each phosphorylase-deficient animal, suggesting an autosomal recessive transmission. Although Myophosphorylase deficiency was described in humans (McArdle's disease) over 40 years ago, these cattle represent the first animal model for this disease.
Gámez Carbonell Josep - One of the best experts on this subject based on the ideXlab platform.
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Contribución a la caracterización clínica y genética de la enfermedad de McArdle
Bellaterra : Universitat Autònoma de Barcelona, 2003Co-Authors: Gámez Carbonell JosepAbstract:Consultable des del TDXTítol obtingut de la portada digitalitzadaINTRODUCCIÓN. La enfermedad de McArdle (Glucogenosis tipo V) es una miopatía metabólica producida por una deficiencia de miofosforilasa, enzima que inicia la degradación del glucógeno con liberación de glucosa-1-fosfato. Los pacientes presentan típicamente intolerancia al ejercicio, mialgias y contracturas. Aproximadamente la mitad de los pacientes presentan mioglobinuria. Se han descrito otras formas de presentación clínica diferentes del fenotipo clásico. Los estudios genéticos moleculares han identificado 32 mutaciones distintas. El defecto molecular más frecuente es la mutación nonsense R49X en el exón 1. Se están describiendo, cada vez con más frecuencia, mutaciones privadas para ciertos grupos étnicos. OBJETIVOS. (1) Identificar el defecto molecular en una serie de 21 familias con individuos afectos de enfermedad de McArdle. (2) Establecer la patogenicidad de esas mutaciones y estudiar la prevalencia de R49X así como de otras mutaciones. (3) Describir los hallazgos clínicos de los afectos. (4) Establecer si existe una correlación genotipo-fenotipo. PACIENTES Y MÉTODOS. Estudiamos 35 pacientes afectos, pertenecientes a 21 familias no relacionadas. Se evaluó los pacientes mediante entrevista, examen físico, análisis bioquímico, estudio neurofisiológico, prueba del ejercicio isquémico del antebrazo, biopsia muscular (en el caso índice de cada una de las familias) y estudios genéticos, incluyendo la secuenciación del gen de la miofosforilasa. Se realizó análisis estadístico de los resultados obtenidos. RESULTADOS. La edad media de los pacientes fue de 42.7 años. La edad media de inicio clínico fue 13.3 años. La edad media del diagnóstico clínico fue 36.2 años. El 43% de los pacientes habían presentado mioglobinuria, nueve habían sufrido más de 5 episodios. La duración media del second wind fue 5.9 minutos. La resistencia durante la prueba del ejercicio isquémico fue 41.6 segundos. La enfermedad fue incapacitante para el trabajo en el 14.2% de los pacientes. El valor medio de CK en reposo fue 1914 UI/L. Nueve pacientes mostraron uricemias superiores a 7.0 mg/dl. La curva de lactato fue plana en todos los pacientes. El fenotipo clásico fue el más frecuente (74.3%). Se observó consanguinidad en 4 familias. Seis familias tenían un patrón pseudodominante. Identificamos 10 mutaciones diferentes. Tres habían sido descritas con anterioridad (R49X, G204S y W797R). Identificamos siete nuevas mutaciones - 5 missense (R93W, L115P, R489W, A669V y N684Y), una nonsense (Y573X) y una splice-junction (K608K). El defecto molecular fue identificado en 62 alelos. Detectamos R49X en 30 alelos (42.85%), W797R en 14, G204S en 7. L115P, R489W, Y573X y K608K en 2 cada uno. N684Y, A669V y R93W en 1 cada uno. Queda aún por identificar el defecto molecular en 8 alelos. Sin embargo, no es ni R49X, ni G204S ni W797R. No encontramos una clara correlación clínica genotipo-fenotipo en la serie. CONCLUSIONES. El test del ejercicio isquémico del antebrazo es la prueba de primera elección al investigar pacientes con probable enfermedad de McArdle. La prevalencia de R49X fue 42.85%, similar a las series francesa y alemana, y ligeramente inferior a la del Reino Unido y Estados Unidos. El concepto de gradiente Norte-Sur propuesto por otros autores debe ser analizado con cautela. Identificamos siete nuevas mutaciones. Estos resultados confirman la heterogeneidad alélica de esta enfermedad en España. La biopsia muscular es una prueba diagnóstica esencial, debido a la alta probabilidad de mutaciones privadas en España. Encontramos una alta prevalencia de heterocigotos sintomáticos en nuestra serie. No observamos una clara correlación genotipo-fenotipo. La mayoría de pacientes con formas de inicio tardío son en realidad formas benignas que empiezan en la infancia y que con la edad se hacen clínicamente más manifiestas. El retraso en el diagnóstico de estos individuos, frecuentemente etiquetados como afectos de alteraciones psicógenas, sugiere la necesidad de programas de divulgación de esta enfermedad entre los profesionales, especialmente aquellos de atención primaria. Palabras Claves: Enfermedad de McArdle. MIM 232600. Glucogenosis tipo V. Miofosforilasa. Miopatía Metabólica. EC 2.4.1.1. Heterogeneidad Alélica. Heterogeneidad Clínica. Correlación Genotipo-Fenotipo. Mutación R49X.INTRODUCTION. McArdle's Disease (Glycogenosis Type V) is a metabolic myopathy caused by a deficiency of Myophosphorylase. This enzyme initiates glycogen breakdown, catalysing glycogen phosphorylitic cleavage to glucose-1-phosphate at a-1,4-glucosydic linkages. McArdle's patients typically present exercise intolerance, premature fatigue, myalgia and cramps. Approximately half present recurrent myoglobinuria. Other clinical presentations have been reported. The Myophosphorylase gene has been cloned, sequenced and assigned to chromosome 11q13. Molecular genetic studies have so far identified 32 different mutations. The most common defect is a nonsense mutation (R49X) in exon-1. Private ethnically-related mutations are being increasingly described, especially in Mediterranean countries. OBJECTIVES: (1) identify the molecular defect in a 21-family series with McArdle's patients, according to clinical and histological criteria, (2) establish the pathogenicity of these mutations and study the prevalence of R49X and other mutations, (3) describe the clinical findings concerning those affected, (4) establish whether there is a genotype-phenotype correlation. PATIENTS AND METHODS: we studied 35 McArdle's patients (20 male, 15 female), from 21 non-related families. Patients were evaluated by interviews, physical examination, biochemical analysis, neurophysiological study, ischemic forearm test, muscle biopsy (in one individual from each family) and genetic studies, including Myophosphorylase gene sequencing. Data were analysed using standard statistical methods. RESULTS: The mean age was 42.7 years old (range 18-85). Mean clinical onset age was 13.3 years old (range 3-51). Mean age of clinical diagnosis was 36.2 years old (range 16-76). Almost 43% of patients presented with myoglobinuria, and 9 patients (25.7%) had over 5 episodes. Mean "second wind" duration was 5.9 minutes. Mean resistance in the forearm ischemic exercise test was 41.6 seconds. Employment was impossible for 14.2% of patients, who were registered as disabled. Mean CK at rest was 1914 UI/L. Nine patients showed uric concentration of over 7.0 mg/dl. The lactate curve in forearm ischemic exercise tests was flat in all patients. In our patients, the classic phenotype was most frequent (74.3%). Five others (14.2%) presented an adult onset form. Two had thoracic pain, one had acute abdominal pain and another had renal failure. Six families showed a pseudo-dominant inheritance pattern. Consanguinity was present in 4 families. Seven families had common ancestry, as they all originated in small population centres. We identified 10 different mutations in the 35 patients. Three had been described (R49X, G204S and W797R). We found seven novel mutations - 5 missense (R93W, L115P, R489W, A669V, and N684Y), one nonsense (Y573X) and a splice junction (K608K). The molecular defect was identified in 62 alleles. We found R49X in 30 alleles (42.85%), W797R in 14 (20%), G204S in 7 (10%). L115P, R489W, Y573X, and K608K in 2 each (2.85%), and N684Y, A669V and R93W in 1 each (1.42%). The molecular defect in 8 alleles has yet to be identified, but it is neither R49X, G204S nor W797R. No clinical genotype-phenotype correlation was found in the series. CONCLUSIONS: Forearm ischemic exercise test is the first choice test when investigating suspected McArdle's patients. R49X prevalence was 42.85%, similar to the French and German series, and slightly less than those in the UK and the USA. The suggested north-south gradient should be therefore analysed with caution. We identified seven novel mutations. These results confirm this disease's allelic heterogeneity in Spain. Muscle biopsy is an important diagnostic test, especially in Spanish patients, due to the likelihood of private mutations. A clear phenotype-genotype correlation was not found. Most late-onset patients in fact have benign forms starting early in life, which become clinically evident with age. Delay in diagnosing these individuals, who are frequently labelled as psychosomatic, suggests the need for awareness-raising programmes among healthcare professionals, especially those involved in primary care. Key word: McArdle's disease. MIM 232600.Glycogenosis type V. Myophosphorylase. Metabolic Myopathy. EC 2.4.1.1. Allelic Heterogeneity. Clinical heterogeneity. Genotype-Phenotype correlation. R49X mutation
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Contribución a la caracterización clínica y genética de la enfermedad de McArdle
'Universitat Autonoma de Barcelona', 2002Co-Authors: Gámez Carbonell JosepAbstract:INTRODUCCIÓN. La enfermedad de McArdle (Glucogenosis tipo V) es una miopatía metabólica producida por una deficiencia de miofosforilasa, enzima que inicia la degradación del glucógeno con liberación de glucosa-1-fosfato. Los pacientes presentan típicamente intolerancia al ejercicio, mialgias y contracturas. Aproximadamente la mitad de los pacientes presentan mioglobinuria. Se han descrito otras formas de presentación clínica diferentes del fenotipo clásico. Los estudios genéticos moleculares han identificado 32 mutaciones distintas. El defecto molecular más frecuente es la mutación nonsense R49X en el exón 1. Se están describiendo, cada vez con más frecuencia, mutaciones privadas para ciertos grupos étnicos. OBJETIVOS. (1) Identificar el defecto molecular en una serie de 21 familias con individuos afectos de enfermedad de McArdle. (2) Establecer la patogenicidad de esas mutaciones y estudiar la prevalencia de R49X así como de otras mutaciones. (3) Describir los hallazgos clínicos de los afectos. (4) Establecer si existe una correlación genotipo-fenotipo. PACIENTES Y MÉTODOS. Estudiamos 35 pacientes afectos, pertenecientes a 21 familias no relacionadas. Se evaluó los pacientes mediante entrevista, examen físico, análisis bioquímico, estudio neurofisiológico, prueba del ejercicio isquémico del antebrazo, biopsia muscular (en el caso índice de cada una de las familias) y estudios genéticos, incluyendo la secuenciación del gen de la miofosforilasa. Se realizó análisis estadístico de los resultados obtenidos.RESULTADOS. La edad media de los pacientes fue de 42.7 años. La edad media de inicio clínico fue 13.3 años. La edad media del diagnóstico clínico fue 36.2 años. El 43% de los pacientes habían presentado mioglobinuria, nueve habían sufrido más de 5 episodios. La duración media del second wind fue 5.9 minutos. La resistencia durante la prueba del ejercicio isquémico fue 41.6 segundos. La enfermedad fue incapacitante para el trabajo en el 14.2% de los pacientes. El valor medio de CK en reposo fue 1914 UI/L. Nueve pacientes mostraron uricemias superiores a 7.0 mg/dl. La curva de lactato fue plana en todos los pacientes. El fenotipo clásico fue el más frecuente (74.3%). Se observó consanguinidad en 4 familias. Seis familias tenían un patrón pseudodominante. Identificamos 10 mutaciones diferentes. Tres habían sido descritas con anterioridad (R49X, G204S y W797R). Identificamos siete nuevas mutaciones - 5 missense (R93W, L115P, R489W, A669V y N684Y), una nonsense (Y573X) y una splice-junction (K608K). El defecto molecular fue identificado en 62 alelos. Detectamos R49X en 30 alelos (42.85%), W797R en 14, G204S en 7. L115P, R489W, Y573X y K608K en 2 cada uno. N684Y, A669V y R93W en 1 cada uno. Queda aún por identificar el defecto molecular en 8 alelos. Sin embargo, no es ni R49X, ni G204S ni W797R. No encontramos una clara correlación clínica genotipo-fenotipo en la serie.CONCLUSIONES. El test del ejercicio isquémico del antebrazo es la prueba de primera elección al investigar pacientes con probable enfermedad de McArdle. La prevalencia de R49X fue 42.85%, similar a las series francesa y alemana, y ligeramente inferior a la del Reino Unido y Estados Unidos. El concepto de gradiente Norte-Sur propuesto por otros autores debe ser analizado con cautela. Identificamos siete nuevas mutaciones. Estos resultados confirman la heterogeneidad alélica de esta enfermedad en España. La biopsia muscular es una prueba diagnóstica esencial, debido a la alta probabilidad de mutaciones privadas en España. Encontramos una alta prevalencia de heterocigotos sintomáticos en nuestra serie. No observamos una clara correlación genotipo-fenotipo. La mayoría de pacientes con formas de inicio tardío son en realidad formas benignas que empiezan en la infancia y que con la edad se hacen clínicamente más manifiestas. El retraso en el diagnóstico de estos individuos, frecuentemente etiquetados como afectos de alteraciones psicógenas, sugiere la necesidad de programas de divulgación de esta enfermedad entre los profesionales, especialmente aquellos de atención primaria.Palabras Claves: Enfermedad de McArdle. MIM 232600. Glucogenosis tipo V. Miofosforilasa. Miopatía Metabólica. EC 2.4.1.1. Heterogeneidad Alélica. Heterogeneidad Clínica. Correlación Genotipo-Fenotipo. Mutación R49X.INTRODUCTION. McArdle's Disease (Glycogenosis Type V) is a metabolic myopathy caused by a deficiency of Myophosphorylase. This enzyme initiates glycogen breakdown, catalysing glycogen phosphorylitic cleavage to glucose-1-phosphate at a-1,4-glucosydic linkages. McArdle's patients typically present exercise intolerance, premature fatigue, myalgia and cramps. Approximately half present recurrent myoglobinuria. Other clinical presentations have been reported.The Myophosphorylase gene has been cloned, sequenced and assigned to chromosome 11q13. Molecular genetic studies have so far identified 32 different mutations. The most common defect is a nonsense mutation (R49X) in exon-1. Private ethnically-related mutations are being increasingly described, especially in Mediterranean countries. OBJECTIVES: (1) identify the molecular defect in a 21-family series with McArdle's patients, according to clinical and histological criteria, (2) establish the pathogenicity of these mutations and study the prevalence of R49X and other mutations, (3) describe the clinical findings concerning those affected, (4) establish whether there is a genotype-phenotype correlation.PATIENTS AND METHODS: we studied 35 McArdle's patients (20 male, 15 female), from 21 non-related families. Patients were evaluated by interviews, physical examination, biochemical analysis, neurophysiological study, ischemic forearm test, muscle biopsy (in one individual from each family) and genetic studies, including Myophosphorylase gene sequencing. Data were analysed using standard statistical methods.RESULTS: The mean age was 42.7 years old (range 18-85). Mean clinical onset age was 13.3 years old (range 3-51). Mean age of clinical diagnosis was 36.2 years old (range 16-76). Almost 43% of patients presented with myoglobinuria, and 9 patients (25.7%) had over 5 episodes. Mean "second wind" duration was 5.9 minutes. Mean resistance in the forearm ischemic exercise test was 41.6 seconds. Employment was impossible for 14.2% of patients, who were registered as disabled. Mean CK at rest was 1914 UI/L. Nine patients showed uric concentration of over 7.0 mg/dl. The lactate curve in forearm ischemic exercise tests was flat in all patients. In our patients, the classic phenotype was most frequent (74.3%). Five others (14.2%) presented an adult onset form. Two had thoracic pain, one had acute abdominal pain and another had renal failure. Six families showed a pseudo-dominant inheritance pattern.Consanguinity was present in 4 families. Seven families had common ancestry, as they all originated in small population centres. We identified 10 different mutations in the 35 patients. Three had been described (R49X, G204S and W797R). We found seven novel mutations - 5 missense (R93W, L115P, R489W, A669V, and N684Y), one nonsense (Y573X) and a splice junction (K608K). The molecular defect was identified in 62 alleles. We found R49X in 30 alleles (42.85%), W797R in 14 (20%), G204S in 7 (10%). L115P, R489W, Y573X, and K608K in 2 each (2.85%), and N684Y, A669V and R93W in 1 each (1.42%). The molecular defect in 8 alleles has yet to be identified, but it is neither R49X, G204S nor W797R. No clinical genotype-phenotype correlation was found in the series.CONCLUSIONS: Forearm ischemic exercise test is the first choice test when investigating suspected McArdle's patients. R49X prevalence was 42.85%, similar to the French and German series, and slightly less than those in the UK and the USA. The suggested north-south gradient should be therefore analysed with caution. We identified seven novel mutations. These results confirm this disease's allelic heterogeneity in Spain. Muscle biopsy is an important diagnostic test, especially in Spanish patients, due to the likelihood of private mutations. A clear phenotype-genotype correlation was not found. Most late-onset patients in fact have benign forms starting early in life, which become clinically evident with age. Delay in diagnosing these individuals, who are frequently labelled as psychosomatic, suggests the need for awareness-raising programmes among healthcare professionals, especially those involved in primary care.Key word: McArdle's disease. MIM 232600.Glycogenosis type V. Myophosphorylase. Metabolic Myopathy. EC 2.4.1.1. Allelic Heterogeneity. Clinical heterogeneity. Genotype-Phenotype correlation. R49X mutation
