KCNA7 encodes Kv1.7, a voltage-gated potassium channel that mediates potassium ion permeability across excitable membranes 1. The protein contains six membrane-spanning domains and a characteristic potassium-selective pore region, forming a rapidly inactivating delayed rectifier potassium channel with a single-channel conductance of 21 pS 2. Unlike other Kv1 family members, KCNA7 has an intronless coding region interrupted by a conserved 1.9 kb intron 3. The gene is preferentially expressed in skeletal muscle, heart, and kidney, with cardiac expression contributing to action potential repolarization 1. KCNA7 shows potent sensitivity to noxiustoxin and stichodactylatoxin but insensitivity to tetraethylammonium and related toxins 2. Beyond cardiac function, KCNA7 participates in volume regulation in human spermatozoa 4 and is upregulated by bone morphogenetic protein-2 in pulmonary artery smooth muscle cells, contributing to control of apoptosis and proliferation 5. Recent evidence indicates KCNA7 methylation correlates with paternal age and can be transmitted to offspring, potentially contributing to developmental disorders 6, and serves as an age estimation marker in forensic applications 7. Direct sequencing excluded KCNA7 as the causative gene for progressive familial heart block I, though regulatory region mutations remain possible 3.