TOR1A and Dystonia: Indeed, some of the same circuit mechanisms may be involved in many different types of dystonia (Defazio et al., 2007; Obermann et al., 2008), including even the generalized, childhood form of dystonia associated with the DYT1 gene, given evidence for reduced D2-family DA receptor availability in non-manifesting DYT1 carriers (Asanuma et al., 2005) and dopamine system abnormalities in DYT1 transgenic mice (Zhao et al., 2008).