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Congenital myasthenic syndromes: spotlight on genetic defects of neuromuscular transmission

Published online by Cambridge University Press:  09 August 2007

Juliane S Müller
Affiliation:
Friedrich-Baur-Institute, Department of Neurology, Ludwig-Maximilians-University, Munich, Germany. Present address: Institute of Human Genetics, University of Newcastle upon Tyne, UK.
Violeta Mihaylova
Affiliation:
Friedrich-Baur-Institute, Department of Neurology, Ludwig-Maximilians-University, Munich, Germany.
Angela Abicht
Affiliation:
Friedrich-Baur-Institute, Department of Neurology, Ludwig-Maximilians-University, Munich, Germany.
Hanns Lochmüller*
Affiliation:
Friedrich-Baur-Institute, Department of Neurology, Ludwig-Maximilians-University, Munich, Germany.
*
*Corresponding author: Hanns Lochmüller, Friedrich-Baur-Institute, Molecular Myology Laboratory, Marchioninistrasse 17, 81377 München, Germany. Tel: +49 89 2180 78180; Fax: +49 89 2180 78184; E-mail: [email protected]

Abstract

The neuromuscular junction (NMJ) is a complex structure that efficiently communicates the electrical impulse from the motor neuron to the skeletal muscle to induce muscle contraction. Genetic and autoimmune disorders known to compromise neuromuscular transmission are providing further insights into the complexities of NMJ function. Congenital myasthenic syndromes (CMSs) are a genetically and phenotypically heterogeneous group of rare hereditary disorders affecting neuromuscular transmission. The understanding of the molecular basis of the different types of CMSs has evolved rapidly in recent years. Mutations were first identified in the subunits of the nicotinic acetylcholine receptor (AChR), but now mutations in ten different genes – encoding post-, pre- or synaptic proteins – are known to cause CMSs. Pathogenic mechanisms leading to an impaired neuromuscular transmission modify AChRs or endplate structure or lead to decreased acetylcholine synthesis and release. However, the genetic background of many CMS forms is still unresolved. A precise molecular classification of CMS type is of paramount importance for the diagnosis, counselling and therapy of a patient, as different drugs may be beneficial or deleterious depending on the molecular background of the particular CMS.

Type
Review Article
Copyright
Copyright © Cambridge University Press 2007

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References

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Further reading, resources and contacts

The congenital myasthenic syndromes entry on GeneReviews can be found at:

Engel, A.G. and Sine, S.M. (2005) Current understanding of congenital myasthenic syndromes. Curr Opin Pharmacol 5, 308-321Google Scholar
Hughes, B.W., Kusner, L.L. and Kaminski, H.J. (2006) Molecular architecture of the neuromuscular junction. Muscle Nerve 33, 445-461CrossRefGoogle ScholarPubMed
Engel, A.G. and Sine, S.M. (2005) Current understanding of congenital myasthenic syndromes. Curr Opin Pharmacol 5, 308-321Google Scholar
Hughes, B.W., Kusner, L.L. and Kaminski, H.J. (2006) Molecular architecture of the neuromuscular junction. Muscle Nerve 33, 445-461CrossRefGoogle ScholarPubMed