A potassium channel mutation in neonatal human epilepsy
Authors
- C. Biervert
- B.C. Schroeder
- C. Kubisch
- S.F. Berkovic
- P. Propping
- T.J. Jentsch
- O.K. Steinlein
Journal
- Science
Citation
- Science 279 (5349): 403-406
Abstract
Benign familial neonatal convulsions (BFNC) is an autosomal dominant epilepsy of infancy, with loci mapped to human chromosomes 20q13.3 and 8q24. By positional cloning, a potassium channel gene (KCNQ2) located on 20q13.3 was isolated and found to be expressed in brain. Expression of KCNQ2 in frog (Xenopus laevis) oocytes led to potassium-selective currents that activated slowly with depolarization. In a large pedigree with BFNC, a five-base pair insertion would delete more than 300 amino acids from the KCNQ2 carboxyl terminus. Expression of the mutant channel did not yield measurable currents. Thus, impairment of potassium-dependent repolarization is likely to cause this age-specific epileptic syndrome.