NIPA1 and hereditary spastic paraplegia: Until now, epilepsy has been described in eight families with SPG6 (Reed et al., 2005; Svenstrup et al., 2011; Arkadir et al., 2014; Lu et al., 2018; Tanti et al., 2020; Fabbro et al., 2021; Spagnoli et al., 2021), including the first index patient in our study, who presented with a complicated form of HSP.