KIF1A and non-syndromic intellectual disability: Mutations in KIF1A have been associated with the motoneuron disease hereditary spastic paraplegia subtype 30 (SPG30; Erlich et al., 2011; Klebe et al., 2012; Citterio et al., 2015; Lee et al., 2015; Ylikallio et al., 2015), hereditary and sensory autonomic neuropathy type 2 (HSAN2; Rivière et al., 2011), and non-syndromic intellectual disability (ID; Hamdan et al., 2011).