SOD1 and amyotrophic lateral sclerosis: The human SOD1 mutant mice (mSOD1) are widely used as ALS models because they exhibit progressive paralysis, pathological protein aggregation, motor neuron degeneration, and gliosis, which are hallmarks of ALS patients.325–327 However, neuron-specific expression of mSOD1 in transgenic mice failed to produce pathology or disease in these mice,328,329 suggesting a role of non-cell-autonomous factors, possibly from non-neuronal cells such as microglia, in ALS pathogenesis.