Higher expression of TREM-1 and NAB2 in patients with BPD only.Higher expression of PU.1 in patients with MDD and a trend for higher expression of TREM-1.Higher expression of ATF3, EGR3, MAFF and MXD1 in patients with both MDD and BPD.No significant difference in expression of DAP12 in either patient group. The gene discussed is TREM1; the disease is major depressive disorder.