Tourette syndrome is defined as part of a spectrum of tic disorders. It is a neuropsychiatric disorder of unknown etiology, with onset in childhood and is characterized by multiple involuntary motor tics and at least one vocal tic. In 90% of children with Tourette syndrome, the tics exist in conjunction with another disorder, most frequently co-occurring with Attention-Deficit Hyperactivity Disorder (ADHD). Therapeutic effects of the plant Cannabis Sativa in patients with either or both Tourette syndrome and ADHD suggest a core involvement of the endogenous cannabinoid system in these disorders. The “endocannabinoid” ligands, their receptors and degradative enzymes constitute the major parts of the “endocannabinoid system.” This proposal is focused on the role of the cannabinoid receptors, members of the G-protein coupled receptor superfamily and of the endogenous cannabinoid system, in the development of motor tic disorders. Our results suggest that postnatal modulation of individual cannabinoid receptors selectively contributes to the development of distinct neuropsychiatric profiles. Sharon Anavi-Goffer, Ph.D. Ariel University Center, Israel Award: $54,000 Commentary: This investigator will study the role played by a particular brain protein – the CB2 receptor – in causing the symptoms of TS and ADHD. She will first determine how many of these receptor molecules are present in different regions of the brain of people with TS and/or ADHD and she will then try to stop these receptors from working. If successful then a new class of drugs to treat TS and ADHD may have been identified. Tourette Association of America Inc. – Research Grant Award 2011-2012