Slowly progressive motor neuron disease with multi-system involvement related to p.E121G SOD1 mutation.

We report the third case of amyotrophic lateral sclerosis related to p.E121G Superoxide dismutase-1 (SOD1) mutation. Besides a sporadic presentation and a slow progressive course, as described in the 2 previously cases, our patient presented with prominent sensory and cerebellar signs. This case report strengthens that p.E121G should be considered as a causal mutation. Slowly upper and lower motor neuron degeneration, even with non-motor clinical features, should prompt a sequencing of SOD1.