SCN5A

(redirected from LQT3)

SCN5A

A gene on chromosome 3p21 that encodes an integral membrane protein and tetrodotoxin-resistant voltage-gated sodium channel alpha subunit, which is expressed primarily in cardiac myocytes and is responsible beginning the action potential as seen on an ECG/EKG.
 
Molecular pathology
SCN5A mutations are long QT syndrome type 3.
References in periodicals archive ?
Based on known triggering stimuli, patients with LQT1 are advised to avoid strenuous exercise (particularly swimming and competitive sports), patients with LQT2 should try to avoid unexpected auditory stimuli, whereas patients with LQT3 may be advised to be monitored or accompanied while sleeping (21).
Antzelevitch, "Sodium channel block with mexiletine is effective in reducing dispersion of repolarization and preventing torsade de pointes in LQT2 and LQT3 models of the long-QT syndrome," Circulation, vol.
channel gene SCN5A, on chromosome 3 results in LQT3 (about 8-10% of cases).
LQT3 genotype experience events during sleep or at rest.
Genetic testing subsequently revealed a LQT3 genotype with a mutation in the SCN5A gene.
The majority of mutations have been identified in LQT1 (40%-55%), LQT2 (35%-45%), and LQT3 (2%-8%), which represent the genes KCNQ1, KCNH2, and SCN5A, respectively.
Finalmente en la forma LQT3 los pacientes presentan arritmias durante el reposo (51).
Sodium channel block with mexiletine is effective in reducing dispersion of repolarization and preventing torsade des pointes in LQT2 and LQT3 models of the long-QT syndrome.
The disorder is phenotypically quite similar to LQT3.
Eighteen unrelated Japanese individuals participated in this study: 10 patients with Brugada syndrome, 1 with IVF without ST segment elevation in the right precordial electrocardiogram leads, 1 with LQT3, and 6 healthy individuals without family histories of syncope or sudden death.
n this study, risk was highest for those who experienced their first cardiac event at a young age (7 years or younger), those with a QTc of more than 500 milliseconds, and those with an LQT2 or LQT3 genotype.
22-25] This was confirmed when Jiang et al[26] mapped the LQT2 and LQT3 genes to chromosome 7q35-36 and to chromosome 3p21-24, respectively.