A case of juvenile-onset amyotrophic lateral sclerosis with a de novo frameshift FUS gene mutation presenting with bilateral abducens palsy

Fused in sarcoma (FUS) is the most common causative gene in juvenile-onset amyotrophic lateral sclerosis (jALS). We presented a case of a 15-year-old Chinese girl with atypical and extremely rare bilateral abducens palsy was caused by a heterozygous c.1520del (p.Gly507Alafs*22) pathogenic frameshift mutation in the FUS gene revealed by whole-exome sequencing. This is the first jALS case presenting with bilateral abducens palsy and carrying de novo FUS genetic variant.