From mutation to myotonia in sodium channel disorders.

  title={From mutation to myotonia in sodium channel disorders.},
  author={Stephen C Cannon},
  journal={Neuromuscular disorders : NMD},
  volume={7 4},
Hyperkalemic periodic paralysis, paramyotonia congenita, and the potassium-aggravated myotonias are all caused by point mutations in the alpha-subunit of a sodium channel expressed selectively in skeletal muscle. This review updates the growing list of genotype-phenotype correlations for these mutations and summarizes the alterations in channel function they produce. A toxin-based in vitro model demonstrates that subtle defects in sodium channel inactivation are sufficient to cause myotonia and… CONTINUE READING