In the last decade, several GWAS [34–40] were conducted on large cohorts of AD patients and controls, which introduced novel genetic risk loci for AD, including ABCA7. These studies provide AD-associated common single-nucleotide polymorphisms (SNPs), referred to as “sentinel” SNPs, which are presumed to be in linkage disequilibrium (LD) with a functional genetic variant. This evidence concerns the gene ABCA7 and Alzheimer disease.