title: Paradigms for the identification of new genes in motor neuron degeneration.
abstract: It is estimated that between 10-20% of amyotrophic lateral sclerosis (ALS) is familial and these cases encompass recessive and dominant modes of inheritance. So far, mutations in three genes, superoxide dismutase 1 (SOD1), the p150 subunit of dynactin (DCTN1), and alsin have been shown to be directly causal for motor neuron degeneration in humans. However, clearly the disorder is genetically heterogeneous and other causal genes remain to be found that explain the vast majority of familial ALS cases. Human genetics can be problematical in that it is difficult to detect linkage in disorders in which multiple loci give similar phenotypes and where families are often small. In addition, the vertical collection of generations is often not possible with late onset disorders. An excellent genetic model of humans is provided by the mouse. We can use mouse models of neurodegeneration to find new genes in the human population. These models are not exact replicas of the human condition, but are the mouse equivalent and are incredibly valuable resources for highlighting genes and biochemical pathways disrupted in ALS and other diseases. In addition mouse models give us access to both control and affected tissues, at all stages of development and disease, thus greatly facilitating our understanding of pathogenesis. They also provide us with model systems for testing new therapies. Here we describe the approach taken to the characterization of new models of motor neuron disease and illustrate this with examples, including a recently characterized mouse model, Legs at odd angles (Loa).
authors.affiliation: Department of Neurodegenerative Disease, Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK.
authors.forename: Majid
authors.initials: M
authors.lastname: Hafezparast
authors.forename: Azlina
authors.initials: A
authors.lastname: Ahmad-Annuar
authors.forename: Holger
authors.initials: H
authors.lastname: Hummerich
authors.forename: Paresh
authors.initials: P
authors.lastname: Shah
authors.forename: Melisa
authors.initials: M
authors.lastname: Ford
authors.forename: Cathy
authors.initials: C
authors.lastname: Baker
authors.forename: Sam
authors.initials: S
authors.lastname: Bowen
authors.forename: Joanne E
authors.initials: JE
authors.lastname: Martin
authors.forename: Elizabeth M C
authors.initials: EM
authors.lastname: Fisher
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics*; D000818:Animals; D002874:Chromosome Mapping / Q000379:methods; D004195:Disease Models, Animal; D000072159:Dynactin Complex; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008869:Microtubule-Associated Proteins / Q000235:genetics; D009046:Motor Neurons; D009154:Mutation; D009410:Nerve Degeneration / Q000235:genetics*; D010641:Phenotype; D013482:Superoxide Dismutase / Q000235:genetics; D000072105:Superoxide Dismutase-1
chemical_list: C000606360:DCTN1 protein, human; C000606364:Dctn1 protein, mouse; D000072159:Dynactin Complex; D008869:Microtubule-Associated Proteins; C000606290:SOD1 protein, human; C000606291:Sod1 protein, mouse; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1