Identifying Chronic Tic Disorder subtypes using clinical diagnostic data
Subramanian, Krishnamurthy*, Tourette International Collaborative Genetics (TIC Genetics) group, and Jinchuan Xing* * Department of Genetics and the Human Genetics Institute of New Jersey, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
Poster # 10
Chronic Tic Disorder (CTD), including Tourette's syndrome (TS) and other tic disorders, is a heterogeneous, childhood-onset neurodevelopmental disorder. CTD is characterized by the presence of motor and/or vocal tics and it affects 1-3% of the population. About 88% of the patients have other neurodevelopmental disorder comorbidities, suggesting shared genetic risk factors for these disorders. Because of high level of heterogeneity and comorbidities, we hypothesize that distinct subtypes exist among CTD patients. Here we identified CTD subtypes and evaluated their discriminatory factors among patients in the Tourette International Collaborative Genetics (TIC Genetics) study. Using Hierarchical Ascendant Clustering, Finite Mixture Modeling, and Bayesian Hierarchical Clustering, we analyzed the TIC Genetics diagnostic data (18 variables) for 1900 CTD patients. These methods identified six distinct clusters: 1. All subjects with CTD but did not meet the diagnosis criteria of TS. These subjects also have a lower prevalence of hispanics and lower prevalence of comorbidities; 2. Subjects with TS. These subjects also have a lower prevalence of hispanics and lower prevalence of comorbidities; 3. Hispanic subjects; 4. Subjects with CTD combined subtype from multi-birth, likely due to environmental conditions during/after birth; 5. Subjects with TS and Trichotillomania and high prevalence of attention deficit obsessive compulsive disorder (OCD); and 6. Subjects with TS with higher prevalence of OCD and ADHD. In summary, our results show that distinct clusters can be identified among CTD patients based on clinical data. In the future, we will conduct stratified analysis of genetic data (e.g., microarray and whole exome sequencing) based on these subtypes to determine the genetic etiology of the subtypes.
LIGHTNING TALK - 2023 MidAtlantic Bioinformatics Conference