The results indicated that BCL7A (AUC: 0.656), GPR18 (AUC: 0.9677), GRB10 (AUC: 0.678), KLRG1 (AUC: 0.661), TDRD9 (AUC: 0.698), and THEM4 (AUC: 0.678) exhibit high diagnostic value for depression (Figure 7E). This evidence concerns the gene GPR18 and major depressive disorder.