IFNG and major depressive disorder: SCZ, major depressive disorder (MDD) and bipolar disorder (BD), among other conditions, have been associated with a persistent inflammatory state, with increased pro-inflammatory markers, such as C-reactive protein, CRP; interleukin (IL)-1β and IL-6; tumor necrosis factor (TNF)-α; transforming growth factor (TFG)-β; interferon (IFN)-γ; or vascular endothelial growth factor (VEGF) [14–22].