BDNF and Behcet disease: In an effort to understand the physiopathology underlying BD, researchers have attempted to identify potential biomarkers for patients with BD and apply the new field of “precision psychiatry.” [12–14] Neurotrophic factors such as brain-derived neurotrophic factor (BDNF) [15, 16] and transforming growth factor beta 1 (TGF-β1) [17] have been proposed as potential peripheral biomarkers in BD.