Biophysical characterization of a new SCN5A mutation S1333Y in a SIDS infant linked to long QT syndrome.
Various entities and genetic etiologies, including inherited long QT syndrome type 3 (LQT3), contribute to sudden infant death syndrome (SIDS). The goal of our research was to biophysically characterize a new SCN5A mutation (S1333Y) in a SIDS infant. S1333Y channels showed the gain of Na(+) channel function characteristic of LQT3, including a persistent inward Na(+) current and an enhanced window current that was generated by a -8 mV shift in activation and a +7 mV shift in inactivation. The correlation between the biophysical data and arrhythmia susceptibility suggested that the SIDS was secondary to the LQT3-associated S1333Y mutation.
Huang
Hai
H
Le Centre de Recherche Université Laval Robert-Giffard, Québec City, QC, Canada.
Millat
Gilles
G
Rodriguez-Lafrasse
Claire
C
Rousson
Robert
R
Kugener
Béatrice
B
Chevalier
Philippe
P
Chahine
Mohamed
M
D001483:Base Sequence; D002460:Cell Line; D004594:Electrophysiology; D006801:Humans; D007223:Infant; D015640:Ion Channel Gating; D008133:Long QT Syndrome / Q000150:complications* / Q000235:genetics* / Q000378:metabolism; D009124:Muscle Proteins / Q000235:genetics* / Q000378:metabolism*; D009154:Mutation / Q000235:genetics*; D062554:NAV1.5 Voltage-Gated Sodium Channel; D018408:Patch-Clamp Techniques; D012694:Serine / Q000235:genetics / Q000378:metabolism; D015222:Sodium Channels / Q000235:genetics* / Q000378:metabolism*; D013398:Sudden Infant Death / Q000235:genetics*
D009124:Muscle Proteins; D062554:NAV1.5 Voltage-Gated Sodium Channel; C568320:SCN5A protein, human; D015222:Sodium Channels; D012694:Serine