CLCN5 encodes a member of the ClC family of chloride ion channels and ion transporters. Mutations in this gene have been found in Dent disease and renal tubular disorders complicated by nephrolithiasis.Sequence analysis suggested that the gene, termed CLCK2, encoded a new member of the CLC family of voltage-gated chloride channels. A 9.5-kb mRNA transcript was expressed predominantly in the kidney.

Fisher et al. (1995) described the isolation and characterization of the complete open reading frame of CLCN5, which encodes a deduced 746-amino acid protein with significant homology to all known members of the family of voltage-gated chloride channels. CLCN5 belongs to a distinct branch of this family, which also includes CLCN3 and CLCN4.