We first investigated whether there was a correlation between severity of depressive symptoms at baseline, as measured by 16-item Quick Inventory for Depression Symptomatology Self Report (QIDS-SR16) scale, and levels of plasma platelet activation markers, E-selectin (CD62E) and P-selectin (CD62P), or increased whole blood platelet aggregation (WBPA) in MDD+/CKD+ patients. The gene discussed is SELP; the disease is major depressive disorder.