Regarding systemic immune/inflammatory status in mental diseases, it was documented that the balance between some pro-inflammatory cytokines, such as TNF-α and IFN-γ, and anti-inflammatory cytokines, such as IL-4 and IL-10, which are involved in the T-helper type 1 (Th1) and T-helper type 2 (Th2) profiles, plays a corollary role in this mental disorders as BD [35] and SZ [36]. The gene discussed is IFNG; the disease is Behcet disease.