likelihood of shared genetic risk. On the other hand, the largest WES study of 802 Tourette’s disorder parent-child trios (including 37% with comorbid OCD) (24) did not find evidence for CHD8 and SCUBE1 as risk genes. Continued WES of trios recruited for OCD and for Tourette’s disorder, currently underway, is likely to clarify the relative contribution of these genes to each disorder. Future studies should also attempt more extensive phenotyping of these patients with predicted damaging mutations in CHD8 and SCUBE1.
