Clinical feature: 

Definition: Hereditary diabetes insipidus is a disorder caused by mutation of genes that impaire either vasopressin production or action. It is clinically characterized by an abnormally large volume of diluted urine.

Epidemiology: Less than 10% of diabetes insipidus can be attributed to hereditary forms.

Diagnostics: 

Differential: As most patients with diabetes insipidus have aquired forms, this has to be excluded primarily.
   Renal response to normal or even elevated AVP levels is impaired in nephrogenic diabetes insipidus.  » » » 
   Central diabetes insipidus is characterized by impaired production of active AVP.  » » » 
   Various Bartter syndromes may cause polyuria too, but the inability of these syndromes to conservate salt is an important differential, although in diabetes insipidus these solute transport mechanisms decompensat because of massive loss water. Polyhydramnios pathognomonic of antenatal Bartter syndrome is never seen in nephrogenic diabetes insipidus.  » » » 

Literature: 

Fujiwara TM et al. (2005) Molecular biology of hereditary diabetes insipidus.