TSPO polymorphism (Rs6971; Ala147Thr) has been also proposed to affect the hypothalamic–pituitary–adrenal axis predisposing carriers to psychiatric disorders, e.g. bipolar disorders, depression, and anxiety [11–14], and affects the response of patients to anxiolytic TSPO drug ligands [15,16]. The gene discussed is TSPO; the disease is depressive disorder.