According to the cholinergic deficit observed in AD (Bartus, Dean, Beer, & Lippa, 1982; Tohgi, Abe, Kimura, Saheki, & Takahashi, 1996), “the cholinergic hypothesis” of AD was introduced (Bartus, Dean, & Beer, 1982) and thereby, the inhibitors of acetylcholine esterase such as tacrine and donepezil were assumed as one of the medical treatments of AD (Lahiri, Rogers, Greig, & Sambamurti, 2004). The gene discussed is ACHE; the disease is Alzheimer disease.