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Spinal Muscular Atrophy

  • Jérémie Vitte
  • Ruben Attali
  • Nasim Warwar
  • Irena Gurt
  • Judith MelkiEmail author
Chapter
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 652)

Abstract

Spinal muscular atrophies (SMA) are frequent autosomal recessive disorders characterized by degeneration of lower motor neurons. SMA are caused by mutations of the survival of motor neuron gene (SMN1) leading to a reduction of the SMN protein amount. The identification of SMN interacting proteins involved in the formation of the spliceosome and splicing changes in SMN-deficient tissues of mutant mice strongly support the view that SMN is involved in the splicing reaction. However, the molecular pathway linking SMN defect to the SMA phenotype remains unclear. From a better knowledge of the genetic basis of SMA and the defects resulting from the mutations of SMN1 in cellular or animal models, several therapeutics strategies have been selected aiming at targeting SMN2, a partially functional copy of SMN1 gene which remains present in patients, or to prevent neurons from death. Refined characterization of the degenerative process in SMA and the identification of the defective molecular pathway downstream from the SMN defect will provide further exciting insight into this disease in the near future. They should contribute to clarify the pathophysiology of SMA, the function of SMN and should help in designing potential targeted or non-targeted therapeutic molecules.

Keywords:

Spinal muscular atrophy SMN Motor neuron disease Splicing 

Notes

Acknowledgements

Work made in our laboratory was supported by INSERM, the University of Evry, the Association Française contre les Myopathies, Families of SMA (U.S.A) and the Foundation Bettencourt Schueller. We gratefully thank Natacha Roblot, Bénédicte Desforges, Gaelle Millet, Vandana Joshi, and Vilayphone Vongsa for their invaluable assistance.

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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Jérémie Vitte
    • 1
  • Ruben Attali
    • 1
  • Nasim Warwar
    • 1
  • Irena Gurt
    • 1
  • Judith Melki
    • 1
    Email author
  1. 1.Department of Human GeneticsHadassah University HospitalJerusalemIsrael

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