It is caused by mutations in the CLCN5 gene (Dent-1 disease, OMIM #300009) in ~ 60 % of cases, in the OCRL gene (Dent-2 disease, OMIM#300555) in ~15 % of cases,, while in the remaining 25 % of cases [3, 4] other unidentified genes are responsible for the disease. This evidence concerns the gene OCRL and Dent disease.