Hereditary spastic paraplegias (HSPs) are neurodegenerative diseases characterized by progressive spasticity of the lower extremities due to axonal degeneration in the corticospinal motor tracts.1,2 Spastic paraplegia type 4 [SPG4, Online Mendelian Inheritance in Man (OMIM) #182601] is the most frequent form, accounting for 40%–60% of autosomal dominant and 20% of sporadic HSPs. Here, SPAST is linked to hereditary spastic paraplegia.