In humans, genes encoding four members of the SCL26A protein family have been identified as disease genes: mutations in the genes encoding SLC26A2/DTD, SLC26A3/DRA, SLC26A4/pendrin and SLC26A5/prestin are associated with diastrophic dysplasia, congenital chloride-losing diarrhoea, Pendred syndrome and human deafness, respectively [1]. The gene discussed is SLC26A4; the disease is Pendred syndrome.