International Mammalian Genome Society

The 16th International Mouse Genome Conference (2002)

Plenary Presentations * Oral Presentations *
Poster Presentations: Complex Genetics and Disease Modifiers * Developmental Genetics * Functional Genomics * Gene Discovery * Genetic Manipulations to Alter Gene Function * Mouse Models: Human Disease and Pharmacogenetics * Sequence Annotation and Comparative Analysis of Genomes *
Attendees * Sponsors * Table of Contents * Photographs * Awards

POSTER 149 - PHYSICAL AND GENETIC MAPPING OF LOA: A GENE INVOLVED IN MOTOR NEURON DEGENERATION

M Hafezparast
Institute of Neurology, University College London

1) Ahmad-Annuar A, 1) Shah P, 1) Witherden AS, 2) Bowen S, 3) Ball S, 3) Peters J, 2) Martin JE, 1) Fisher EMC
1) Institute of Neurology, University College London, 2) Department of Histopathology, Queen Mary College, London, 3) MRC Mammalian Genetics Unit

The Loa mouse was identified in the progeny of a male mouse treated with ENU. These mice exhibit progressive motor function deficit in their hind limbs, which has an autosomal dominant pattern of inheritance. Heterozygous Loa/+ mice have a normal life span and can be identified by a characteristic clasping of hind limbs when suspended by the tail. They perform progressively more poorly in the rotarod test and balance of coordination, when compared with their wild type littermates. Histopathological analysis has revealed a significant decrease in the number of anterior horn cells in aged heterozygous animals, but no muscle denervation has been observed, indicating that Loa is a neuropathy. Homozygotes, however, die within 24 hours after birth, with apoptosis throughout the CNS, although the gross anatomy of the progeny is apparently normal, indicating normal development. We have mapped the Loa to the distal portion of Mmu12 and in our effort to identify this gene, we have generated genetic, physical, radiation hybrid, and transcription maps of this region. These maps contain STSs that include microsatellite markers as well as SNPs, some of which are within the genes in the Loa region.  Several genes are being analysed as candidates for the Loa, but this region contains loci such as an imprinted gene, a transcription factor, and genes involved in tumour necrosis factor pathway, which are of broader interest.We will present an update on the phenotype and positional cloning of this mutation.