The CLCN family of voltage-dependent chloride channel genes comprises nine members (CLCN1-7, Ka and Kb) which demonstrate quite diverse functional characteristics while sharing significant sequence homology. Chloride channel 4 has an evolutionary conserved CpG island and is conserved in both mouse and hamster. This gene is mapped in close proximity to APXL (Apical protein Xenopus laevis-like) and OA1 (Ocular albinism type I), which are both located on the human X chromosome at band p22.3. The physiological role of chloride channel 4 remains unknown but may contribute to the pathogenesis of neuronal disorders. Alternate splicing results in two transcript variants that encode different proteins.CLCN4 (Chloride Voltage-Gated Channel 4) is a Protein Coding gene. Diseases associated with CLCN4 include Mental Retardation, X-Linked 49 and Non-Syndromic X-Linked Intellectual Disability. Among its related pathways are Transport of glucose and other sugars, bile salts and organic acids, metal ions and amine compounds and Ion channel transport. GO annotations related to this gene include ion channel activity and antiporter activity. An important paralog of this gene is CLCN5.