OBJECTIVETo elucidate the molecular and electrophysiological mechanisms of Brugada syndrome through functional analysis of a novel SCN5A gene mutation G1712C.

METHODSA recombinant plasmid pRc

RESULTSAn HEK293 cell line that stably expressed Nachannel β1-subunit was successfully established. After transient transfection with the WT subunit, large Nacurrents were recorded from the stable β1-cell line. Transient transfection with the G1712C subunit, however, did not elicit a Nacurrent in the cells.

CONCLUSIONCompared with normal Nachannel, the wild-type channel exhibits a similar sodium current. The characteristic kinetics of sodium channel of WT-hH1 was identical to that in normal cardiac muscle cell, and the missense mutation (G1712C) in the P-loop region of the domain IV may have caused the failure of sodium channel expression.