SPAST and hereditary spastic paraplegia: Mutations in SPAST account for up to 60% of familial HSP cases in northern Europe and North America, and of these spastin-HSP cases 10–20% may be caused by large rearrangements, predominantly deletions (Beetz et al., 2006; Depienne et al., 2007; Sulek et al., 2013; Schule et al., 2016; Chelban et al., 2017).