Lack of hypotension in NCC knockout mice (Schultheis et al., 1998; Loffing et al., 2004; Alshahrani et al., 2017a), but hypotension in 50% of Gitelman’s syndrome patients (Cruz et al., 2001; below), may reflect differences in Na+ handling in mice and humans. Here, SLC12A3 is linked to Gitelman syndrome.