MOLECULAR ANALYSIS OF THE HETEROGENEITY O F HEREDITARY MONOSYMPTOMATIC SENSORINEURAL HEARING-LOSS

Background: Genetic characterization of hereditary hearing impairment has progressed considerably with the mapping of nine chromosomal loci for monosymptomatic autosomal-inherited hearing loss over the last thr ee years. Methods: Following thorough clinical evaluation, linkage ana lysis using microsatellite markers was performed in two large families from Westphalia/West Germany. Results: For all the dominant (DFNA1-4) and three autosomal-recessive loci (DFNB1-3) described to date, linka ge was finally excluded. Conclusions: A high degree of genetic heterog eneity must be assumed. Identification of individual genes for monosym ptomatic sensorineural hearing loss by linkage analysis in large pedig rees may help in molecular differentiation of hearing.