The pathogenesis of AD and Parkinson’s disease involve neuroinflammatory activities (Gelders et al., 2018), oxidative stress (Jiang et al., 2016), mitochondrial dysfunction (Morais and De Strooper, 2010), and dysfunction in brain-derived neurotrophic factor (Mohammadi et al., 2018). The gene discussed is BDNF; the disease is Parkinson disease.