A gain-of-function <i>KCNJ2</i> D172N mutation in KCNJ2-encoded Kir2.1 channels underlies one form of short QT syndrome (SQT3), which is associated with increased susceptibility to arrhythmias and sudden death.
These findings are a significant advancement of our knowledge and understanding of the phenotype-genotype relationship of arrhythmia syndromes related to KCNJ2 mutations.
The loss-of-function mutations in KCNJ2 in ATS1 affect the excitability of both skeletal and cardiac muscle, which underlies the cardiac arrhythmias and periodic paralysis associated with ATS.
KCNJ2 gene screening in atypical ATS phenotypes is of clinical importance because more than half of mutation carriers express atypical phenotypes, despite their arrhythmia severity.
This biophysical phenotype, distinct from typical Andersen-Tawil syndrome mutations, suggests a specific mechanism for PKA-dependent I(K1) dysfunction for this KCNJ2 mutation, which correlates with adrenergic conditions underlying the clinical arrhythmia.
The purpose of this study was to identify and characterize mutations in the KCNJ2-encoded inward rectifier potassium channel Kir2.1 from patients referred for genetic arrhythmia testing.
Arrhythmia documented during cardiac arrest is rapid ventricular tachycardia; ICD is effective therapy for cardiac arrest in patients with PVT due to KCNJ2 mutation.