Expanding the Phenotypic Spectrum of ERLIN1-Related SPG62: Report of Two Siblings With Behavioral Features and Hyperacusis.

Hereditary spastic paraplegia type 62 (SPG62) is a neurodegenerative disorder, with more than 20 individuals reported to date. This ultra-rare entity is inherited in an autosomal recessive manner and has been associated with ERLIN1 variants. In addition, ERLIN1-related biallelic variants have been linked to early-onset amyotrophic lateral sclerosis (ALS). We present two siblings with slowly progressive spastic paraplegia, with mild intellectual decline, behavioral findings, and hyperacusis. This study expands the clinical spectrum of hereditary spastic paraplegia associated with ERLIN1.