Characterizing and Distinguishing Progressive Phenotypes in Nonsyndromic Autosomal Dominant Hearing Impairment

Abstract

The progressive nonsyndromic autosomal dominant (DFNA) traits considered here are those linked to the DFNA2, DFNA5, DFNA6/14(/38), DFNA9, DFNA10, DFNA15, DFNA20/26 and DFNA21 loci. This is a report on our use of the method of `Age Related Typical Audiograms' (ARTA). This method was developed especially to characterize progressive hearing impairment phenotypes. Pure tone threshold data are plotted in a familiar audiogram-like format covering, where possible, decade steps in age (decade audiograms). Such plots, if characteristic and specific enough, can be used as phenotype `fingerprints'. The threshold features array is an additional tool that can be used for statistical testing between fingerprints corresponding to different traits. The issue of genotype-phenotype correlation is dealt with in the case of some loci with multi-family presentation and sufficiently established genotypes.