Hence, to determine potential specific differentially expressed genes (DEGs) that are responsible for microglial inflammation between AD and depression, we first analyzed the overlap of common DEGs between disease-associated microglia (DAM) genes (Keren-Shaul et al., 2017) and depression-associated (DA) genes (Gao et al., 2018) using the Venn function, and found the common gene, CST7, which is an endogenous inhibitor of cysteine proteases. This evidence concerns the gene CTSB and major depressive disorder.