OPRM1 and Alzheimer disease: However,conflicting results stem from large genome-wide association studies (GWAS) andcandidate gene studies (Kong etal., 2017), which could not replicate an association between AD andOPRM1 genotype, corresponding with a recent report onconverging evidence against an association between the OPRM1 A118Gpolymorphism and alcohol consumption and sedation (Sloan et al., 2018).