Barttin CLCNK-type accessory beta subunit (BSND)

Barttin is an essential beta accessory subunit for ClC-Ka and ClC-Kb chloride channels, operating primarily in the kidney and inner ear[1][2][4]. It enables the correct localization, trafficking, and functional activation of these ion channels, critical for urine concentration, systemic acid-base balance, and the electrical potential underlying hearing[1][2][4]. Mutations in BSND lead to Bartter syndrome type IV, distinguished by severe salt-losing nephropathy and sensorineural deafness[2][4]. Barttin also serves as a diagnostic biomarker for chromophobe renal cell carcinoma. While not a direct drug target yet, its role regulating specific chloride channels suggests future utility for therapies targeting salt and water homeostasis[3].

Other names

BarttinBSNDBARTDFNB73deafness, autosomal recessive 73Bartter syndrome, infantile, with sensorineural deafnessbarttin CLCNK type accessory beta subunitbarttin CLCNK-type chloride channel accessory beta subunit

Drugs (future potential) would modulate ClC-K channel gating and trafficking via interaction with barttin, affecting water and salt excretion and possibly hearing physiology[3].