Congenital Myasthenic Syndromes

Part of the Current Clinical Neurology book series (CCNEU)


The congenital myasthenic syndromes (CMS) are rare hereditary disorders of neuromuscular transmission. They are characterized by fatiguable fluctuating muscle weakness that can vary in severity. Diagnosis is important since these are treatable conditions, and appropriate medication and interventions may avert life-threatening respiratory crises that occur in some syndromes. The advent of next-generation sequencing has facilitated the discovery of many genes that harbor CMS-associated mutations. Up to 30 different genes may be involved. These may encode proteins directly involved in signal transmission or in controlling the formation and maintenance of the neuromuscular synapse, and the severity of the disorders can vary from fatality in utero or the neonatal period to near-asymptomatic weakness. Recent findings show that many genes whose functions are not restricted to the neuromuscular junction can also cause myasthenic weakness, such as genes involved in protein glycosylation pathways or neurotransmitter release. In some of the more recently identified syndromes, the myasthenic weakness is only one component of a more complex phenotypic spectrum, which introduces additional challenges in patient treatment.


Congenital myasthenic syndromes Neuromuscular junction Synaptic transmission Synaptic stability AChR Neurotransmitter release Glycosylation Ion channel kinetics 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Nuffield Department of Clinical NeurosciencesUniversity of Oxford, Neurosciences Group, Weatherall Institute of Molecular Medicine, The John Radcliffe HospitalOxfordUK

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