The investigators of the 2019 GWAS9 and 2019 GWAX7 did a series of functional genomic analyses to prioritise putative risk genes (table 2). In the GWAS, a priority score was constructed for genes located within 500 KB of the linkage disequilibrium region for the risk locus associated with each lead SNP, which comprised the sum of several categories of evidence: exonic functional annotation, expression and eQTLs in all tissues and in those relevant to Alzheimer’s disease, correlation between expression and tau burden, differential expression in Alzheimer’s disease, or evidence based on biological pathways. By contrast, the investigators of the GWAX study used an approach that functionally annotated genome–wide significant SNPs, then mapped them to genes on the basis of localisation within a gene, association with gene expression in any tissue, and the presence of chromatin interactions. They then did a gene–based association analysis that estimated the aggregate effect of all SNPs in a gene on a trait to identify genes that were significantly associated with Alzheimer’s disease. Finally, they further prioritised genes for which the functionally annotated SNPs affected gene
