Chloride Channel Protein 4 (CLCN4)

The predicted 760-amino acid protein contained 12 hydrophobic domains and shared sequence and structural similarities with all the previously isolated members of the family of voltage-gated chloride channels. The gene, termed CLCN4, for chloride channel 4, contained at least 10 exons spanning 60 to 80 kb. In contrast with most genes isolated from the Xp22.3 region, CLCN4 did not share homology with the Y chromosome, but was conserved in mouse and hamster. Expression studies demonstrated a 7.5-kb transcript that is particularly abundant in skeletal muscle and also detectable in brain and heart. Thus, this gene encodes a newly identified voltage-gated chloride channel.Since no recombination was observed between the RFLP and the OA1 mutation in 3 informative families, the marker will be useful for genetic counseling in OA1.