BCHE variants (BCHE and CHE2 Loci) associated with erythrocyte acetylcholinesterase inhibition in farmers exposed to pesticides. The findings do not support the premise that inhibitor therapy should target BuChE so as to prevent increased levels of BuChE from hydrolyzing acetylcholine in AD cerebral cortex. Thus, low BuChE in a patient's CSF may predict extensive incorporation in neuritic plaques, increased neurotoxicity and greater central neurodegeneration.