CD84 expression levels were significantly different relative expression levels among three group (4.59E-5±1.46E-5 in MDD group, 6.42E-5±8.64E-6 in SSD group, and2.41E-5±5.94E-6 in control group, F = 3.52, p = 0.03), CTNS expression levels were1.79E-5±4.78E-6 in MDD group, 2.91E-5±4.71E-6 in SSD group, and 1.06E-5±1.81E-6 in control group. This evidence concerns the gene CTNS and major depressive disorder.