OBJECTIVES:

I. Define the phenotype and genotype of previously unrecognized types of familial diabetes insipidus (FDI) in kindreds with atypical or novel forms of FDI.

PROTOCOL OUTLINE: Participants undergo a series of tests to determine the presence, absence, cause, natural history, clinical status, and mode of inheritance of their type of diabetes insipidus (DI). The studies include measurements of basal fluid intake and urine output, plasma vasopressin during standard fluid deprivation or waterload/saline infusion tests, and changes in water balance during a therapeutic trial of DDAVP. If clinically indicated, echocardiograms and assays of plasma catecholes and renin are also completed.

Linkage analysis is performed for all participants; kindreds with the Marfan-like syndrome are also studied for the fibrillin-1 genotype.

Participants determined to have DI are treated with desmopressin for 2 days.

• Familial diabetes insipidus (DI) in atypical or novel form, e.g.: Dipsogenic DI Neurohypophyseal DI
• Affected and unaffected members of kindreds eligible