The purpose of this project is to identify common and rare genetic variants that influence risk for developing Obsessive-Compulsive Disorder (OCD) and Tourette Syndrome (TS). These studies are funded by multiple United States NIH grant awards (R01 MH110427, R01 MH124675, R21 MH134170). We will use genotype array data from up to 5,000 OCD cases (currently around 3500 genotyped) and up to 10,000 controls (currently 4,000 available) for studies of common variation. We will utilize the 'ricopili' pipeline for quality control of these data, genotype imputation and formal genome-wide assocation study. Details regarding the ricopili pipeline can be found elsewhere (https://sites.google.com/a/broadinstitute.org/ricopili/). We are also in the process of generating exome sequencing data for these same 5,000 cases, and will be matching them to around 5,000 controls for studies of rare variation. The quality control and variant calling workflow for these exome sequence data will follow GTK best practices for calling of small variants (https://gatk.broadinstitute.org/hc/en-us/articles/360035535932-Germline-short-variant-discovery-SNPs-Indels-) and for large structural variants (https://gatk.broadinstitute.org/hc/en-us/articles/360035531152). The sequence data and processed variant calls will be utilized for gene-based association tests between OCD/TS case status and the presence of ultra-rare damaging coding variation. We have rich phenotypic data on all of our OCD and TS cases, and we plan additional case-focused association tests between clinical features (ex: sex, condition severity, age at onset, family history) and common and rare variants. Our study is a collaboration between the groups of Christian Rück at KI and David Mataix-Cols at KI.