SCNN1A (Sodium Channel Epithelial 1 Subunit Alpha): SCNN1A encodes the alpha subunit of the epithelial sodium channel (ENaC), a key regulator of sodium balance and fluid homeostasis in epithelial tissues such as the lungs, kidneys, and colon. This channel plays a critical role in the absorption of sodium from extracellular fluids, a process essential for maintaining blood pressure, fluid volume, and electrolyte balance. The SCNN1A subunit is fundamental for ENaC's proper assembly, localization, and function. Mutations in the SCNN1A gene can lead to altered channel activity, contributing to various diseases, including pseudohypoaldosteronism type 1 (PHA1), a disorder characterized by salt...