Genome-wide scans for performance measures in three cognitive domains in two large clinically ascertained and three community-based cohorts revealed GWS associations with four well-established AD loci (BIN1, CR1, MS4A6A, and APOE) and eight loci not previously genetically linked to AD or cognitive decline (ULK2, CDK14, PURG, LINC02712, LOC107984373, NCALD, PTPRD, and OSGIN1), as well as with GRN which has been associated with AD and several other dementing illnesses [7, 10, 78–80]. This evidence concerns the gene GRN and Alzheimer disease.