Genetic variations in DISC1 were found to modulate prefrontal-limbic connectivity in schizophrenia, and hereditary spastic paraplegia was strongly associated with mutations in SPG4 and SPG11, leading to progressive degeneration of corticospinal tracts (He et al. 2021) (Faber et al. 2018) (Rezende et al. 2015). This evidence concerns the gene DISC1 and hereditary spastic paraplegia.