FAMILIAL MONDINI-DYSPLASIA

Objectives/Hypothesis: To determine the mode of inheritance of familia l nonsyndromic Mondini dysplasia. Study Design: Correlative clinical g enetic analysis of a single kindred. Methods: Clinical history, physic al examination, audiologic analysis, computed tomography of the tempor al bones, and cytogenetic analysis. Results: The male proband, three a ffected sisters, and an affected brother are offspring of unaffected p arents. The mother and an unaffected brother have audiologic findings suggestive of heterozygous carrier status for a recessive hearing loss gene. Conclusions: Pedigree analysis indicates autosomal recessive in heritance in this family. The observed inheritance and clinical, audio logic, and radiologic findings are different from those previously des cribed for another family with nonsyndromic Mondini dysplasia.(1) The phenotype in this study family therefore represents a distinct subtype , indicating clinical and genetic heterogeneity of this disorder. This information should facilitate future molecular linkage analyses and g enetic counselling of patients with inner ear malformations.