Genetics and molecular biology of deafness.

With increased emphasis on early detection of hearing impairment, more babies are likely to be referred at younger ages to otolaryngologists for evaluation. With a diminution in the number of infants who have hearing impairment as a result of such factors as maternal infection, neonatal sepsis, or ototoxicity, the relative importance of detecting a genetic cause of newborn hearing impairment is likely to increase. Therefore, the otolaryngologist must become familiar with common causes of hereditary hearing impairment and the ways in which the newborn should be evaluated for hereditary hearing impairment. Advancements are rapidly being made in the ability to detect genes that cause hearing impairment, and we are now on the threshold of discovering ways to use gene therapy to prevent or treat hereditary deafness.