ECE1 and Alzheimer disease: CLU is a confirmed AD gene from genome-wide association study, and encodes apolipoprotein J, which has been shown to chaperone re-entry of Aβ into the brain following export of the peptide from the brain into the blood.49 Interestingly, genes encoding two peptidases known to degrade Aβ were also decreased in expression in blood pre–post intervention as part of the vacation effect: MME (P=0.00019) and ECE1 (P=0.0037).