SOD1 and amyotrophic lateral sclerosis: In fact, although the SOD1G93A transgenic mouse has been a bedrock for ALS research and the most important and well-used model for well over a decade, it manifests abnormal phenotypic features that might arise from extreme SOD1 protein overexpression rather than being the effect of the SOD1G93A mutation itself and motor neuron death generally occurs over short periods of time.