The qPCR results showed that UBE2K mRNA was highly expressed in the peripheral blood of MDD patients and was positively correlated with HAMD-17 (Pearson correlation coefficient r=0.5049, p=0.0061) and HAMD-24 (Pearson correlation coefficient r=0.5613, p=0.0019) scores (Figure 6C-D). This evidence concerns the gene UBE2K and major depressive disorder.