KCNK12 (potassium two pore domain channel subfamily K member 12) encodes a leak potassium channel that functions as a K(+) channel subunit capable of homo- and heterodimerization to form functional channels with distinct regulatory properties [UniProt]. The channel can heterodimerize with KCNK13 to conduct K(+) outward rectifying currents at the plasma membrane, while homodimers are primarily retained in the endoplasmic reticulum and may traffic to the cell surface upon activation signals. KCNK12 is abundantly expressed in mammalian kidney nephron segments including the proximal tubule, thick ascending limb, connecting tubule, and cortical collecting duct, where it fulfills important functions in volume regulation and ion homeostasis 1. The channel is also expressed in mammalian central neurons, suggesting roles in maintaining neuronal phenotype 2. KCNK12 has clinical significance as a methylation biomarker for pancreatic cancer detection; methylated KCNK12 DNA in pancreatic juice achieved an AUC of 0.88 for pancreatic cancer discrimination and was among the most important genes distinguishing COVID-19 infected from recovered patients in respiratory immune profiling 34. A KCNK12 SNP variant (rs748780) shows population-specific associations with MSH2 gene variants across diverse ethnic groups 5. KCNK12 genetic gains have been detected in malignant peripheral nerve sheath tumors and synovial sarcomas 67.