THAP1 and Dystonia: Altered striatal dopaminergic neurotransmission has been reported in several animal models of monogenic dystonia, such as reduced D2 receptor expression observed in the striatum of patients with both TOR1A and THAP1 variants (Carbon et al., 2009), indicating that dopaminergic signaling abnormalities represent convergent mechanisms downstream of several apparently unrelated genetic defect (Napolitano et al., 2010; Yokoi et al., 2011; Frederick et al., 2019).