Fagerheim et al. (1996) described a large Norwegian family with autosomal dominant nonsyndromic progressive high-tone hearing loss. In the majority of affected family members examined with successive audiograms, the hearing loss was greater than 45 dB by age ... Fagerheim et al. (1996) described a large Norwegian family with autosomal dominant nonsyndromic progressive high-tone hearing loss. In the majority of affected family members examined with successive audiograms, the hearing loss was greater than 45 dB by age 15 years.