These data extend the range of known KCNQ1 mutations associated with both recessive and dominant forms of congenital long QT syndrome, and demonstrate that the R518X allele may be associated with or without congenital deafness.
KCNH2 codes for the HERG ion channel and mutations in the gene are associated with congenital long-QT syndrome (LQTS), and in the family of this case of SIDS, the mutation was associated with Torsades de pointes tachycardia, making SIDS the most likely outcome of congenital LQTS.
We conclude that the A390V mutation disrupted binding with PMCA4b, released inhibition of nNOS, caused S-nitrosylation of SCN5A, and was associated with increased late sodium current, which is the characteristic biophysical dysfunction for sodium-channel-mediated LQTS (LQT3).
Interaction with GM130 during HERG ion channel trafficking. Disruption by type 2 congenital long QT syndrome mutations. Human Ether-à-go-go-Related Gene.
However, the SCN5A variants R568H and A993T can be classified as pathogenic LQTS3 causing mutations, while R222stop and R2012H are novel BrS causing mutations.
We have recently identified a missense mutation, G604S, in the human ether-a-go-go related gene (hERG) that results in a malignant phenotype in a full pedigree of a Chinese congenital long QT syndrome (LQTS) family.
Inherited long QT syndrome (LQTS) recently has been associated with mutations in genes coding for potassium (KVLQT1, KCNE1, and HERG) or sodium (SCN5A) ion channels involved in regulating either sodium inward or potassium outward currents of heart cells, resulting in prolongation of the repolarization period.
Utility and limitations of exome sequencing as a genetic diagnostic tool for conditions associated with pediatric sudden cardiac arrest/sudden cardiac death.
Congenital long-QT syndrome (LQTS) is caused by mutations of genes encoding the slow component of the delayed rectifier current (LQT1, LQT5), the rapid component of the delayed rectifier current (LQT2, LQT6), or the Na(+) current (LQT3), resulting in ST-T-wave abnormalities on the ECG.
Inherited long QT syndrome (LQTS) recently has been associated with mutations in genes coding for potassium (KVLQT1, KCNE1, and HERG) or sodium (SCN5A) ion channels involved in regulating either sodium inward or potassium outward currents of heart cells, resulting in prolongation of the repolarization period.
Mutation and gender-specific risk in type 2 long QT syndrome: implications for risk stratification for life-threatening cardiac events in patients with long QT syndrome.
With this method, we identified the mutation(s) in all four patients with congenital LQTS (KCNQ1A341V, KCNH2 N633D, KCNH2 2768Cdel and KCNE1 K70 N Y81C double mutations).