International Mammalian Genome Society

17th International Mouse Genome Conference

9-12 November 2003, Braunschweig, Germany

Plenary Presentations * Oral Presentations *
Poster Presentations: Behavioural Genetics and Genomics * Development and Stem Cells * Functional Genome Analysis * Mouse Models of Human Disease * Mouse System Biology Bioinformatics * Multigenic and Multifactorial Trait Analysis * Nutrition and Metabolic Disease * Phenotyping Methods Imaging * The Genetics and Genomics of Infectious Disease *
Verne Chapman Memorial Lecture * Table of Contents * Sponsor/Exhibitor List * Awards * Photographs

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POSTER 119 - CHARACTERISATION AND GENETIC MAPPING OF THE PROGRESSIVE DEAFNESS MOUSE MUTANT OBLIVIOUS

Spiden S L
Wellcome Trust Sanger Institute

Co-Authors: 2) Fuchs H, 2) Hrabe de Angelis M, 1) Steel KP
Institutions: 1) Wellcome Trust Sanger Institute, 2) GSF Center of Environment and Health Institute of Experimental Genetics

Mouse mutagenesis programs have provided a valuable resource to investigate the genetics of many hereditary diseases. Mutations are induced using the chemical N-ethyl-N-nitrosourea (ENU) and offspring are subsequently screened for specific phenotypes, including hearing and balance defects. Characterisation and mapping of the dominantly-inherited progressive deafness mutant Oblivious, identified from such an ENU mutagenesis program, is presented.

Oblivious (Obl) mutants exhibit a normal ear flick response (Preyer reflex) to a calibrated 90dB SPL 20kHz tone-burst at two weeks of age. A progressive reduction in this reflex is seen in Obl mutants from 1-2 months, with most Obl mutants exhibiting no Preyer reflex by two months. Cleared samples of Obl mutant inner ears suggest that the morphology of the inner ear is normal. Scanning electron microscopy (SEM) analysis of the organ of Corti in Obl mutants at three months revealed missing outer hair cells (OHC) throughout the length of the cochlea, with most extensive degeneration and OHC loss present in the base. There also appears to be some inner hair cell loss in the base. An intraspecific backcross was set up between Obl and C3H mice. 91 backcross mice were typed with 61 microsatellite markers throughout the genome and a region of linkage identified on the distal half of mouse chromosome 6. Fine mapping and analysis of candidate genes within the region is currently underway.

Supported by the Medical Research Council, Defeating Deafness and the EC (contract number: CT97-2715 and QLG2-CT-1999-00988).