A separate analysis of gene expression in microglia from patients with major depressive disorder (MDD) revealed that 81 genes, such as CD163, MKI67, SPP1, CD14, FCGR1A/C, and C1QA/B/C, were found to be downregulated in the microglia of the occipital cortex. The gene discussed is SPP1; the disease is major depressive disorder.