KCNJ1 and Hypertension: Furthermore, recent data from Lifton's group demonstrated that heterozygous mutations in SLC12A3 (encoding the thiazide-sensitive Na-Cl cotransporter), SLC12A1 (encoding the Na-K-Cl cotransporter NKCC2), and KCNJ1 (encoding the K+ channel ROMK) discovered in the general population have been associated with lower BP and a 60% reduction in the development of hypertension [24].