Abstract
Electrophysiological properties in various regions of the heart differ, and these intrinsic heterogeneities between the cardiac compartments are rooted in the regional differences in expression of ion channel genes and gap junction subunit genes. The transcriptional regulation that orchestrates the development of the heart also plays an essential role in regulation of expression of ion channel and gap junction genes.
Abnormal cardiac electrical function and arrhythmias in the postnatal heart may stem from a developmental abnormality causing maintained changes in gene regulation. Fetal and childhood arrhythmias can be of genetic origin.
However, environmental factors such as hypoxia, autoimmune disease, and drugs also play an important role in clinical scenarios. Genome-wide association studies demonstrate that common genetic variation in (heart) developmental genes modulates electrocardiographic indices of conduction and repolarization and susceptibility to arrhythmia.