SLC40A1 and Pendred syndrome: Transient/constitutive reduction of Kcnj10 protein expression under free radical stress could be the pathobiologic mechanism of sudden hearing loss that could be not limited just to Pendred syndrome. SLC26A4 and SLC40A1 genes belong to the same (super)family and might be involved, by regulating inflow/outflow of different ions, to maintain specific homeostasis and redox potency [63].