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 183 - ANALYSIS OF MODIFIER LOCI FOR THE NEUROLOGICAL- AND THE SPERMIOGENESIS PHENOTYPE OF THE WOBBLER MOUSE

Schmitt-John T
Developmental Biology and Molecular Pathology, University of Bielefeld

Co-Authors: Mussmann A, Heimann P, Jockusch H, Ulbrich M
Institutions: Developmental Biology and Molecular Pathology, University of Bielefeld

The recessive wobbler (wr) mutation of the mouse causes a spinal muscular atrophy (SMA), a progressive degeneration of motoneurons which secondarily leads to an athophy of skeletal muscles. The wobbler mouse serves as an animal model for human SMAs and the amyotrophic lateral sclerosis (ALS). Besides the neurological effect the wobbler mutation causes a spermiogenesis defect leadingto roundheaded sperms and male infertility comparable to human globozoospermia. In different crosses we observed a wide variation of the severity of both phenotypes. QTL mapping was performed and independent modifier loci for both the neurological- and the spermiogenesis wobbler phenotype could be mapped. One of the neurological modifier loci (wrmod1) on Chr 14 could be confirmed by breeding partially congenic animals and a candidate interval was defined by recombination events. Within this interval the genes coding for the light and the middle neurofilament subunit (Nfl and Nfm) are located, which were considered as positional and physiological candidates for wrmod1 since pronounced neurofilament deposits were observed in degenerating neurons of severely affected wobbler individuals. Sequence analysis of the genes revealed three strain-specific variations within the Nfm gene, one of which affects a highly conserved KSP-phosphorylation site. We suggest that these strain-specific allele-variations in the Nfm gene might be responsible for the modification of the neurological wobbler phenotype.