SLC18A1 and Anxiety: A recent study has shown that VMAT1 knockout in mice lead to differential dopamine signaling [52], and several other studies have revealed the association of the 136Thr with a variety of psychiatric phenotypes including alcohol dependence [38, 53], bipolar disorders [34], autism [39], anxiety [37, 38], maladaptive impulsivity, depressiveness, and neuroticism [38].