For example, acetylcholinesterase (ACHE), which is commonly associated with β-amyloid plaques and neurofibrillary tangles in the brains of patients with Alzheimer's Disease (AD; Talesa, 2001), is not among the annotated genes for AD in the KEGG database (Kanehisa et al., 2017). Here, ACHE is linked to Alzheimer disease.