Takeaway
Mutations in the fused in sarcoma (FUS) gene, including the p.P525L mutation, demonstrated a greater level of clinical heterogeneity than the typically associated motor neuron degeneration.
Why this matters
Awareness of atypical amyotrophic lateral sclerosis (ALS) phenotypes presenting with features such as tremor, movement disorders, dropped-head syndrome, and cognitive impairments, may aid clinicians in diagnosis.