1965; Neiberger 1991; Grimble 1994; Houterman et al. 1997; Markovich et al. 1998; Sagawa et al. 1998b), NSAID use (Sagawa et al. 1998a), acidosis (Frick and Durasin 1986), Vitamin D depletion(Fernandes et al. 1997), hypothyroidism (Sagawa et al. 1999b), and hypokalemia (Markovich et al. 1999), which down‐regulated the NaS1 transporter whereas sulfate depletion, hyperthyroidism (Tenenhouse et al. 1991), growth hormone (Sagawa et al. 1999a) and vitamin D suppletion (Fernandes et al. 1997) up‐regulated the NaS1 transporter. The gene discussed is GH1; the disease is Hypokalemia.