A novel detrimental homozygous mutation in the WFS1 gene in two sisters from nonconsanguineous parents with untreated diabetes insipidus por Dimitrios T. Papadimitriou, Kleanthis Kleanthous, Emmanouil Manolakos, Anatoly Tiulpakov, Thomas Nikolopoulos, Alexandros Delides, Gerasimos Voros, Argyrios Dinopoulos, George Zoupanos, Anastasios Papadimitriou, Georgios Mastorakos, Fumihiko Urano