OPRM1 and Alzheimer disease: Indeed, β-casomorphin-7 (BCM7, Tyr-Pro-Phe-Pro-Gly-Pro-Ile; a bioactive cow-milk peptide derivative that plays a role in the development of cow-milk protein allergy) was shown to elevate MOR mRNA expression in PBMCs (5-day treatment of the isolated cells; 1–1000 ng/mL) of children with AD (62 children) but not in PBMCs of healthy children (40 subjects).