A novel heterozygous variant of FUS gene associated with juvenile ALS and premature tremor onset: a case report.

Juvenile amyotrophic lateral sclerosis (JALS) is neurodegenerative disease of the upper and lower motor neurons of rare incidence. Although fused in sarcoma (FUS) mutations in JALS patients have been associated with movement disorders, here we described the case of a young girl with very early onset of tremor, years before commencement of weakness; once symptoms of JALS were stablished, a typical rapid disease progression from spinal to bulbar symptoms were noticed. Genetic testing revealed a novel mutation in FUS gene causative of a protein dysfunction. This case emphasizes the fact that some mutations within the FUS in JALS patients may produce a symptom onset with tremor.