Sodium channel mutations in paramyotonia congenita and hyperkalemic periodic paralysis

  title={Sodium channel mutations in paramyotonia congenita and hyperkalemic periodic paralysis},
  author={Louis J. Pt{\'a}{\vc}ek and Launce G. Gouw and Hubert Kwiecinski and Philip G. McManis and Jerry R. Mendell and Richard J. Barohn and A. L. George and Rebert L. Barchi and Margaret Robertson and M. Leppert},
  journal={Annals of Neurology},
Clinical and electrophysiological data have outlined a spectrum of similar yet distinct periodic paralyses, including potassium‐sensitive (hyperkalemic periodic paralysis [HYPP]) and temperature‐sensitive (paramyotonia congenita [PC]) forms. Recent work has revealed that these disorders result from allelic defects in the x‐subunit of the adult, human skeletal muscle sodium channel. We report an additional mutation, a leucine ‐ arginine substirution in the ss segment of domain 4 (L1433R), that… 

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