 Mutations in the "CLCN5" gene cause a X-linked recessive nephropathy named Dent disease (Dent disease 1 MIM#300009) characterized by excessive urinary loss of low-molecular-weight proteins and of calcium (hypercalciuria), nephrocalcinosis (presence of calcium phosphate aggregates in the tubular lumen and/or interstitium) and nephrolithiasis (kidney stones).The human "CLCN5" gene (MIM#300008, reference sequence NG_007159.2) is localized in the pericentromeric region on chromosome Xp11.23.It extends over about 170 Kb of genomic DNA, has a coding region of 2,238 bp and consists of 17 exons including 11 coding exons (from 2 to 12).