These genes include Fez1, which is involved in oligodendrocyte and myelin formation (Chen et al., 2017); Nf2, which is involved in axonal regeneration in peripheral neurogenic injury (Mindos et al., 2017); Slc39s12, which is required for neurite outgrowth (Davis et al., 2021); brain-derived neurotrophic factor (BDNF), which is important for neural activity and synaptic plasticity (Oh et al., 2019; Wang et al., 2019), and the cholecystokinin gene (Cck), which has neuroprotective effects in Alzheimer’s disease and Parkinson’s disease (Reich and Holscher, 2024). This evidence concerns the gene CCK and Parkinson disease.