Funded by the U.S. National Institutes of Health (R01 MH073856, K24 MH087913, M01 RR000036, P30 NS057105, C06 RR020092, UL1 RR024992). The Tourette Syndrome Association and its Greater Missouri chapter helped with recruitment. Tamara Hershey, Meghan C. Campbell, Elda Shipley, Jonathan Koller, Samantha Ranck, Kathryn Vehe, and Gary Queensen contributed to the overall study from which the data reported here were drawn.