The destruction of cholinergic neurons in the basal forebrain and reduction of choline acetyltransferase (EC 2.3.1.6; ChAT) and acetylcholinesterase (EC 3.1.1.7; AChE) activity in brain tissues in AD patients were first reported in 1976 and 1977 [3,4]. Here, CHAT is linked to Alzheimer disease.