Inflammatory cytokines (especially tumor necrosis factor‐α [TNF‐α], interleukin‐1β [IL‐1β], interleukin‐6 [IL‐6], and interleukin‐17 [IL‐17]) have been proposed as modulators for key psychobiological substrates (such as hypothalamic–pituitary–adrenal axis dysregulation and monoamine neurotransmitter metabolism), which are implicated in the pathogenesis of anxiety and depression.10, 11, 12. This evidence concerns the gene IL17A and major depressive disorder.