In particular, our observed increase in FAAH in the monocytes of AD patients not only corroborates previous findings that reported an increase in this enzyme due to an altered epigenetic regulation of its gene promoter in total peripheral blood mononuclear cells of late-onset AD patients [7], but extends those findings and identifies monocytes as the immune cell population mostly responsible for reducing the eCB tone in AD. This evidence concerns the gene FAAH and Alzheimer disease.