The results revealed that the expression of ACKR1, CHGA, and CCDC47 were lower in the MDD group than that in normal controls for both datasets (p < 0.05), whereas CCDC47 expression was higher in the MDD group than that in normal controls for the GSE44593 and GSE54566 datasets (p < 0.05). This evidence concerns the gene CCDC47 and major depressive disorder.