HLA-DRB1 and Alzheimer disease: A large GWAS study, including 1,126,563 individuals 90,338 (46,613 proxy) cases and 1,036,225 (318,246 proxy) controls, identified 38 AD risk loci including CD33 and HLA-DRB1 with SNP variants (RS1354106T>G) and (RS1846190G>A) consecutively [20].