Lack of potassium current in W309R mutant KCNQ3 channel causing benign familial neonatal convulsions (BFNC).

Department of Neurology, Fukushima Medical University, School of Medicine, Fukushima, Japan.
Epilepsy research (Impact Factor: 2.48). 02/2009; 84(1):82-5. DOI: 10.1016/j.eplepsyres.2008.12.003
Source: PubMed

ABSTRACT BFNC is an autosomal dominant epileptic disorder caused by mutations of KCNQ2 or KCNQ3 potassium channel gene. W309R missense mutation in KCNQ3 gene was previously reported in a family with BFNC. In this study, potassium currents were recorded from HEK293 cells expressing both W309R mutant KCNQ3 and wild type KCNQ2 channels. We found a lack of potassium current in W309R mutant KCNQ3 and KCNQ2 channels, which can explain the hyper-excitability of CNS in patients with BFNC.

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May 28, 2014