The mRNA expression levels of CHT (fold change for controls vs. MDD suicides: 1.000 ± 0.237 vs. 0.460 ± 0.117, P = 0.025) and CHRNB3 (1.000 ± 0.308 vs. 0.394 ± 0.126, P = 0.046) were significantly reduced in suicides relative to those in controls. This evidence concerns the gene SLC5A7 and major depressive disorder.