Histopathology and molecular genetics of hearing loss in the human

Hearing loss is among the most common disabilities of man. It has been esti mated that over 70 million individuals in the world are hearing impaired wi th pure tone averages greater than 55 dB. A genetic etiology is thought to be responsible for over half of early onset hearing loss and at least one t hird of late onset hearing loss. In this review, examples of the histopatho logy of the inner ear in known genetic syndromes in the human will be prese nted in order to provide a structural basis for understanding molecular mec hanisms of development and maintenance in the inner ear, and to serve the e ssential function of validating the applicability of animal genetic models of hearing loss to the human condition. (C) 2001 Elsevier Science Ireland L td. All rights reserved.