In addition, based on the evidence that striatal A2AR expression might be increased in PD patients with dyskinesia (Calon et al., 2004; Ramlackhansingh et al., 2011) and in dyskinetic animal models of PD (Jenner et al., 2009), it has also been suggested that adenosine A2A sites might be a potential pharmacologic target for reducing LIDs (Jenner et al., 2009; Ramlackhansingh et al., 2011; Huot et al., 2013; Kanda and Uchida, 2014). Here, ADORA2A is linked to Parkinson disease.