Functional analysis of Ca3.2 T-type calcium channel mutations linked to childhood absence epilepsy

Epilepsia. 2006 Mar;47(3):655-8. doi: 10.1111/j.1528-1167.2006.00482.x.


Purpose: Childhood absence epilepsy (CAE) is an idiopathic form of seizure disorder that is believed to have a genetic basis.

Methods: We examined the biophysical consequences of seven mutations in the Ca(v)3.2 T-type calcium channel gene linked to CAE.

Results: Of the channel variants examined, one of the mutants, a replacement of glycine 848 in the domain II-S2 region with serine, resulted in significant slowing of the time courses of both activation and inactivation across a wide range of membrane potentials. These changes are consistent with increased channel activity in response to prolonged membrane depolarizations.

Conclusions: Taken together, these findings suggest that such little changes in channel gating may contribute to the etiology of CAE.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium Channels, T-Type / genetics*
  • Calcium Channels, T-Type / physiology
  • Cells, Cultured
  • Child
  • Epilepsy, Absence / genetics*
  • Epilepsy, Absence / physiopathology
  • Glycine / genetics
  • Glycine / physiology
  • Humans
  • In Vitro Techniques
  • Ion Channel Gating / genetics
  • Ion Channel Gating / physiology
  • Membrane Potentials / genetics
  • Mutation / genetics*
  • Mutation / physiology
  • Mutation, Missense / genetics
  • Mutation, Missense / physiology
  • Rats
  • Serine / genetics


  • Calcium Channels, T-Type
  • Serine
  • Glycine