The first 0.1-Mb duplication involves chromosomal region 2q37.3, comprising KIF1A and AQP12A. The KIF1A gene, encoding an axonal transporter of synaptic vesicles involved in nuclear migration and neurogenesis [63], has been associated with hereditary sensory and autonomic neuropathy type II and in autosomal recessive spastic paraparesis as well as spastic paraplegia [19–21]. The gene discussed is KIF1A; the disease is Spastic paraplegia.