Increases in ACh action due to the administration of acetylcholinesterase inhibitors or direct mAChRs agonists alleviate cognitive deficits in Alzheimer’s disease (Cummings, 2003), Parkinson’s disease (Fagerström et al., 1994; Holmes et al., 2011) and schizophrenia patients (Shekhar et al., 2008). This evidence concerns the gene ACHE and Parkinson disease.