ETV1 is a sequence-specific transcriptional activator that binds DNA containing the consensus pentanucleotide 5'-CGGA[AT]-3' and serves critical roles in both cardiac electrophysiology and stem cell differentiation. In the heart, ETV1 directs a rapid conduction transcriptional program; cardiomyocyte-specific deletion results in conduction abnormalities, decreased expression of rapid conduction genes (Gja5, Scn5a, Nkx2-5), and His-Purkinje system hypoplasia 1. Forced ETV1 expression in ventricular myocytes and human induced pluripotent stem cell-derived cardiomyocytes promotes a His-Purkinje phenotype with increased sodium currents 1. During cardiac pressure overload, ETV1 expression is downregulated in the left atrium, contributing to atrial electrical and structural remodeling and arrhythmia susceptibility 2. In stem cell biology, ETV1 and related ETV factors regulate biophysical properties and lineage commitment; loss of ETV1 impairs pancreatic progenitor formation and disrupts germ-layer organization 3. ETV1 is also implicated in cancer: recurrent TMPRSS2-ETV1 gene fusions occur in prostate cancer, present in approximately 23 of 29 samples in one cohort 4, and ETV1 copy number gains are associated with progression and metastasis in pancreatic ductal adenocarcinoma 5. Chr7 translocations involving ETV1 also drive Ewing sarcoma 6.