Dehydration [30], as well as anisosmotic disorders described in patients [31]–[37], and deficiency of osmoregulatory proteins such as vasopressin V2 receptor [38], or aquaporins 1 and 2, in mouse models [39], [40], have been reported to cause hypernatremia with plasma osmolality values of 360–430 mOsm/kg. The gene discussed is AQP1; the disease is Hypernatremia.