To study the link between changes in cholinergic signaling, both inherited and post-transcriptional, and the neurodegenerative diseases AD and PD, we used human post-mortem brains from AD (n = 79), PD (n = 67), and the GTEx dataset (n = 651) to search for co-inherited SNPs in both the coding and non-coding regions of the BCHE gene and in the 3′-UTR region of the ACHE gene. The gene discussed is BCHE; the disease is Alzheimer disease.