V Dominant Midfrequency Hearing Loss

Four families are presented in which members were affected with a dominantly transmitted progressive hearing loss. Although there was some variation in the severity of hearing loss and in the frequencies affected, the loss probably began in the first decade, and was noticed by affected persons in the second or third decades of life. The midfrequencies (1000 to 4000 Hz) were generally affected first, with progression in later years to involvement of all frequencies. Other audiometric tests, including the speech reception threshold, speech discrimination, SISI and tone decay, suggested a cochlear locus for the hearing loss. Vestibular tests showed no abnormalities.