At the time of study, 24 subjects were taking acetyl cholinesterase inhibitors; 14 subjects with Alzheimer's disease (donepezil, n = 9 and galantamine, n = 5) and 10 subjects with dementia with Lewy bodies (donepezil, n = 5; galantamine, n = 4; and rivastigmine, n = 1). The gene discussed is BCHE; the disease is Alzheimer disease.