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Background: Persistent motor or vocal tic disorder (PMVT) has been hypothesized to be a forme fruste of Tourette syndrome (TS). Although the primary diagnostic criterion for PMVT (presence of motor or vocal tics, but not both) is clear, less is known about its clinical presentation., Objective: The goals of this study were to compare the prevalence and number of comorbid psychiatric disorders, tic severity, age at tic onset, and family history for TS and PMVT., Methods: We analyzed data from two independent cohorts using generalized linear equations and confirmed our findings using meta-analyses, incorporating data from previously published literature., Results: Rates of obsessive-compulsive disorder (OCD) and attention deficit hyperactivity disorder (ADHD) were lower in PMVT than in TS in all analyses. Other psychiatric comorbidities occurred with similar frequencies in PMVT and TS in both cohorts, although meta-analyses suggested lower rates of most psychiatric disorders in PMVT compared with TS. ADHD and OCD increased the odds of comorbid mood, anxiety, substance use, and disruptive behaviors, and accounted for observed differences between PMVT and TS. Age of tic onset was approximately 2 years later, and tic severity was lower in PMVT than in TS. First-degree relatives had elevated rates of TS, PMVT, OCD, and ADHD compared with population prevalences, with rates of TS equal to or greater than PMVT rates., Conclusions: Our findings support the hypothesis that PMVT and TS occur along a clinical spectrum in which TS is a more severe and PMVT a less severe manifestation of a continuous neurodevelopmental tic spectrum disorder. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society., (© 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.)

Trichotillomania/hair pulling disorder (HPD) and excoriation/skin picking disorder (SPD) are childhood-onset, body-focused repetitive behaviors that are thought to share genetic susceptibility and underlying pathophysiology with obsessive-compulsive disorder (OCD) and Tourette syndrome (TS). We sought to determine the prevalence of DSM-5 HPD and SPD in TS patients, and to identify clinical factors most associated with their co-morbidity with TS. Participants included 811 TS patients recruited from TS specialty clinics for a multi-center genetic study. Patients were assessed using standardized, validated semi-structured interviews. HPD and SPD diagnoses were determined using a validated self-report questionnaire. HPD/SPD prevalence rates were calculated, and clinical predictors were evaluated using regression modeling. 3.8 and 13.0% of TS patients met DSM-5 criteria for HPD and SPD, respectively. In univariable analyses, female sex, OCD, and both tic and obsessive-compulsive symptom severity were among those associated with HPD and/or SPD. In multivariable analyses, only lifetime worst-ever motor tic severity remained significantly associated with HPD. Female sex, co-occurring OCD, ADHD, and motor tic severity remained independently associated with SPD. This is the first study to examine HPD and SPD prevalence in a TS sample using semi-structured diagnostic instruments. The prevalence of HPD and SPD in TS patients, and their association with increased tic severity and co-occurring OCD, suggests that clinicians should screen children with TS and related disorders for HPD/SPD, particularly in females and in those with co-occurring OCD. This study also helps set a foundation for subsequent research regarding HPD/SPD risk factors, pathophysiology, and treatment models.

Objective: Tourette's disorder (TD) and autism spectrum disorder (ASD) share clinical features and possibly an overlapping etiology. The aims of this study were to examine ASD symptom rates in participants with TD, and to characterize the relationships between ASD symptom patterns and TD, obsessive-compulsive disorder (OCD), and attention-deficit/hyperactivity disorder (ADHD)., Method: Participants with TD (n = 535) and their family members (n =234) recruited for genetic studies reported TD, OCD, and ADHD symptoms and completed the Social Responsiveness Scale Second Edition (SRS), which was used to characterize ASD symptoms., Results: SRS scores in participants with TD were similar to those observed in other clinical samples but lower than in ASD samples (mean SRS total raw score = 51; SD = 32.4). More children with TD met cut-off criteria for ASD (22.8%) than adults with TD (8.7%). The elevated rate in children was primarily due to high scores on the SRS Repetitive and Restricted Behaviors (RRB) subscale. Total SRS scores were correlated with TD (r = 0.27), OCD (r = 0.37), and ADHD (r = 0.44) and were higher among individuals with OCD symptom-based phenotypes than for those with tics alone., Conclusion: Higher observed rates of ASD among children affected by TD may in part be due to difficulty in discriminating complex tics and OCD symptoms from ASD symptoms. Careful examination of ASD-specific symptom patterns (social communication vs. repetitive behaviors) is essential. Independent of ASD, the SRS may be a useful tool for identifying patients with TD with impairments in social communication that potentially place them at risk for bullying and other negative sequelae., (Copyright © 2017 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.)

Objective: Phenotypic heterogeneity in Tourette syndrome is partly due to complex genetic relationships among Tourette syndrome, obsessive-compulsive disorder (OCD), and attention deficit hyperactivity disorder (ADHD). Identifying symptom-based endophenotypes across diagnoses may aid gene-finding efforts., Method: Assessments for Tourette syndrome, OCD, and ADHD symptoms were conducted in a discovery sample of 3,494 individuals recruited for genetic studies. Symptom-level factor and latent class analyses were conducted in Tourette syndrome families and replicated in an independent sample of 882 individuals. Classes were characterized by comorbidity rates and proportion of parents included. Heritability and polygenic load associated with Tourette syndrome, OCD, and ADHD were estimated., Results: The authors identified two cross-disorder symptom-based phenotypes across analyses: symmetry (symmetry, evening up, checking obsessions; ordering, arranging, counting, writing-rewriting compulsions, repetitive writing tics) and disinhibition (uttering syllables/words, echolalia/palilalia, coprolalia/copropraxia, and obsessive urges to offend/mutilate/be destructive). Heritability estimates for both endophenotypes were high and statistically significant (disinhibition factor=0.35, SE=0.03; symmetry factor=0.39, SE=0.03; symmetry class=0.38, SE=0.10). Mothers of Tourette syndrome probands had high rates of symmetry (49%) but not disinhibition (5%). Polygenic risk scores derived from a Tourette syndrome genome-wide association study (GWAS) were significantly associated with symmetry, while risk scores derived from an OCD GWAS were not. OCD polygenic risk scores were significantly associated with disinhibition, while Tourette syndrome and ADHD risk scores were not., Conclusions: The analyses identified two heritable endophenotypes related to Tourette syndrome that cross traditional diagnostic boundaries. The symmetry phenotype correlated with Tourette syndrome polygenic load and was present in otherwise Tourette-unaffected mothers, suggesting that this phenotype may reflect additional Tourette syndrome (rather than OCD) genetic liability that is not captured by traditional DSM-based diagnoses.

Objective: Obsessive-compulsive disorder (OCD) and Tourette's syndrome are highly heritable neurodevelopmental disorders that are thought to share genetic risk factors. However, the identification of definitive susceptibility genes for these etiologically complex disorders remains elusive. The authors report a combined genome-wide association study (GWAS) of Tourette's syndrome and OCD., Method: The authors conducted a GWAS in 2,723 cases (1,310 with OCD, 834 with Tourette's syndrome, 579 with OCD plus Tourette's syndrome/chronic tics), 5,667 ancestry-matched controls, and 290 OCD parent-child trios. GWAS summary statistics were examined for enrichment of functional variants associated with gene expression levels in brain regions. Polygenic score analyses were conducted to investigate the genetic architecture within and across the two disorders., Results: Although no individual single-nucleotide polymorphisms (SNPs) achieved genome-wide significance, the GWAS signals were enriched for SNPs strongly associated with variations in brain gene expression levels (expression quantitative loci, or eQTLs), suggesting the presence of true functional variants that contribute to risk of these disorders. Polygenic score analyses identified a significant polygenic component for OCD (p=2×10(-4)), predicting 3.2% of the phenotypic variance in an independent data set. In contrast, Tourette's syndrome had a smaller, nonsignificant polygenic component, predicting only 0.6% of the phenotypic variance (p=0.06). No significant polygenic signal was detected across the two disorders, although the sample is likely underpowered to detect a modest shared signal. Furthermore, the OCD polygenic signal was significantly attenuated when cases with both OCD and co-occurring Tourette's syndrome/chronic tics were included in the analysis (p=0.01)., Conclusions: Previous work has shown that Tourette's syndrome and OCD have some degree of shared genetic variation. However, the data from this study suggest that there are also distinct components to the genetic architectures of these two disorders. Furthermore, OCD with co-occurring Tourette's syndrome/chronic tics may have different underlying genetic susceptibility compared with OCD alone.

Objective: Obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) are heritable neurodevelopmental disorders with a partially shared genetic etiology. This study represents the first genome-wide investigation of large (>500 kb), rare (<1%) copy number variants (CNVs) in OCD and the largest genome-wide CNV analysis in TS to date., Method: The primary analyses used a cross-disorder design for 2,699 case patients (1,613 ascertained for OCD, 1,086 ascertained for TS) and 1,789 controls. Parental data facilitated a de novo analysis in 348 OCD trios., Results: Although no global CNV burden was detected in the cross-disorder analysis or in secondary, disease-specific analyses, there was a 3.3-fold increased burden of large deletions previously associated with other neurodevelopmental disorders (p = .09). Half of these neurodevelopmental deletions were located in a single locus, 16p13.11 (5 case patient deletions: 0 control deletions, p = .08 in the current study, p = .025 compared to published controls). Three 16p13.11 deletions were confirmed de novo, providing further support for the etiological significance of this region. The overall OCD de novo rate was 1.4%, which is intermediate between published rates in controls (0.7%) and in individuals with autism or schizophrenia (2-4%)., Conclusion: Several converging lines of evidence implicate 16p13.11 deletions in OCD, with weaker evidence for a role in TS. The trend toward increased overall neurodevelopmental CNV burden in TS and OCD suggests that deletions previously associated with other neurodevelopmental disorders may also contribute to these phenotypes., (Copyright © 2014 American Academy of Child and Adolescent Psychiatry. All rights reserved.)

The direct estimation of heritability from genome-wide common variant data as implemented in the program Genome-wide Complex Trait Analysis (GCTA) has provided a means to quantify heritability attributable to all interrogated variants. We have quantified the variance in liability to disease explained by all SNPs for two phenotypically-related neurobehavioral disorders, obsessive-compulsive disorder (OCD) and Tourette Syndrome (TS), using GCTA. Our analysis yielded a heritability point estimate of 0.58 (se = 0.09, p = 5.64e-12) for TS, and 0.37 (se = 0.07, p = 1.5e-07) for OCD. In addition, we conducted multiple genomic partitioning analyses to identify genomic elements that concentrate this heritability. We examined genomic architectures of TS and OCD by chromosome, MAF bin, and functional annotations. In addition, we assessed heritability for early onset and adult onset OCD. Among other notable results, we found that SNPs with a minor allele frequency of less than 5% accounted for 21% of the TS heritability and 0% of the OCD heritability. Additionally, we identified a significant contribution to TS and OCD heritability by variants significantly associated with gene expression in two regions of the brain (parietal cortex and cerebellum) for which we had available expression quantitative trait loci (eQTLs). Finally we analyzed the genetic correlation between TS and OCD, revealing a genetic correlation of 0.41 (se = 0.15, p = 0.002). These results are very close to previous heritability estimates for TS and OCD based on twin and family studies, suggesting that very little, if any, heritability is truly missing (i.e., unassayed) from TS and OCD GWAS studies of common variation. The results also indicate that there is some genetic overlap between these two phenotypically-related neuropsychiatric disorders, but suggest that the two disorders have distinct genetic architectures., Competing Interests: The following authors have read the journal's policy and have the following conflicts: CLBu: Currently receiving funding for TS clinical trials from Otsuka Pharmaceutical, JFL: recevies research support from NIH and Grifols, LLC as well royalties from John Wiley and Sons, McGraw Hill, and Oxford University Press, MARic: received honoraria from Lundbeck, and research funding from Great-West Life Assurance Company of Canada and Eli Lilly Canada Ltd, MCR: grant from CNPq (Brazilian National Counsil) and has received research grants and/or consultancy honoraria from Novartis and Shire, DR: received consulting fees for Shire, JMS: received research support, honoraria and travel support from the Tourette Syndrome Association (TSA), DJS: received research grants and/or consultancy honoraria from Abbott, Astrazeneca, Biocodex, Eli-Lilly, GlaxoSmithKline, Jazz Pharmaceuticals, Johnson & Johnson, Lundbeck, Orion, Pfizer, Pharmacia, Roche, Servier, Solvay, Sumitomo, Takeda, Tikvah, and Wyeth, TVF: received research funding from NIMH (K08 MH099424-01), the Simons Foundation, Allison Foundation, and Shire, PS: received research support for this study from the Tourette Syndrome Association (TSA), Tourette Syndrome Foundation of Canada and NIH, DY: received research support from the Tourette Syndrome Association (TSA) and NIH, MMR: received grants from the Tourette's Action-UK, TSA-USA, honoraria from Janssen-Cilag, and book royalties from Wiley - Blackwell, David Fulton/Granada/Taylor Francis, Oxford University Press and Jessica Kingsley Publishers, is a Patron of Tourette's Action (UK), sits on the Medical Advisory Board of the Italian Tourette Syndrome Association and The Tourette Syndrome Foundation of Canada, DAC: NIH/NIMH funding for K01 MH072952 and R34 MH090149, SLR: participated in research funded by Medtronic and Cyberonics, JRW: Past employee of F. Hoffmann-La Roche and current employee of Pfizer, SW: received lecture honoraria from Janssen Cilag, AstraZeneca and Eli Lilly, research funds Swiss National Science Foundation (SNF), Deutsche Forschungsgemeinschaft, EU FP7, HSM Hochspezialisierte Medizin of the Kanton Zurich, Switzerland, JV: funding from Seaside Therapeutics, Novartis, Roche Pharmaceuticals, Forest, and SynapDx. Consulting/Advisory Board for Novartis, JTM: Tourette Syndrome Association-Speaker honoraria; Otuska-research grant; Roche-consultant; 1R01MH079487-01A1, JLK: honoraria from Roche, Eli Lilly, and Novartis, PDA: Unrestricted research grant from DNA Genotek SLG, HJG, ML, DLP, SES, NL, JHS, CLBa, LB, FB, GBB, OJB, MHB, RMB, RDB, DC, CC, JCCS, DCC, MCC, SC, DVC, EHC, VC, NJC, BAC, LKD, DDen, DDef, RD, EMD, YD, CKE, KE, PF, NBF, PJG, ERG, HG, MAG, BDG, VGT, SH, GLH, GAH, SMJH, PH, AGH, CI, JJ, MAJ, CLK, RAK, JAK, AIK, BK, RK, SHL, LL, CLi, CLo, TLL, FM, CAM, LMM, WM, SCMR, ECM, RM, JM, HM, DLM, ALN, BMN, GN, HN, WCO, BAO, RAO, LO, AJP, MTP, CNP, CP, YP, DP, TJR, VIR, MARid, GAR, SR, ARL, ASS, JS, BS, HSS, ES, JAT, AVVD, HV, MW, YW, JY, HGMW, PE, BC, RR have declared that no competing interests exist.

Tourette's disorder (TD) frequently co-occurs with attention-deficit/hyperactivity disorder (ADHD) and obsessive compulsive disorder (OCD). While the relationship between TD and OCD suggests that they share etiological factors, the exact relationship between TD and ADHD is less clear. The goal of the current analyses was to understand better the familial relationship between DSM-IV ADHD and TD. Direct interview diagnostic data from a case-control study of 692 relatives of 75 comorbid TD and ADHD (TD + ADHD), 74 TD without ADHD (TD Only), 41 ADHD without TD (ADHD Only), and 49 control probands were analyzed. Hierarchical loglinear modeling was used to explore association patterns between TD, ADHD, and OCD or sub-clinical OCD (OCD/OCDsub) diagnoses among the 190 affected probands and their 538 relatives. The presence of OCD or OCDsub diagnosis in a proband was associated with a significantly increased risk of comorbid TD + ADHD in his/her relatives. The finding of an association between TD, ADHD and a proband OCD/OCDsub diagnosis was unexpected. The current results suggest that TD, ADHD, and OCD symptoms have overlapping neurobiology when occurring in families of TD and/or ADHD probands., (Copyright © 2011 Wiley-Liss, Inc.)

Objective: To determine whether the four-factor category-based obsessive-compulsive disorder (OCD) symptom structure from a previous confirmatory factor analysis (CFA) may be appropriately used in child, adolescent, and adult groups. Symptom dimensions are increasingly used as quantitative traits in genetic, neuroimaging, and treatment studies of OCD across all ages. Identification of a category-based OCD symptom dimension structure that is validated for use across child, adolescent, and adult age groups is necessary to guide ongoing translational research., Method: Four OCD samples comprising 356 individuals were divided into child, adolescent, and adult groups. The fit of the only CFA-defined four-factor model was compared across these independent age group samples. Multiple-group CFA using maximum likelihood estimation assessed adequacy of fit comparing unconstrained and measurement weight-constrained models. The fit of previous exploratory factor analysis-defined three- and five-factor models on adults was also examined using CFA., Results: A four-factor solution provided adequate but imperfect fit across age groups, with comparable indices to the only previous OCD CFA: factor 1 (aggressive/sexual/religious/somatic/checking); factor 2 (symmetry/ordering/counting/repeating); factor 3 (contamination/cleaning), and factor 4 (hoarding). Models in which factor loadings were constrained and unconstrained across the three age groups yielded comparable model fit. Factors were highly correlated and were not mutually exclusive. The four-factor solution provided an improved fit to both three- and five-factor solutions using CFA across the three age groups., Conclusions: A four-factor, CFA-defined, category-based model of OCD symptom dimensions is adequate for use in children, adolescents, and adult age groups. The factor structure of this multiple age group sample has limitations and is imperfect, but current findings support the comparability of the defined latent OCD dimensions across age groups. Further work is needed to optimize a comprehensive symptom dimension model reflecting clinical heterogeneity for use in emergent translational studies.

Context: Obsessive-Compulsive Disorder (OCD) is a debilitating illness with putative glutamatergic abnormalities. Two separate proximal haplotypes in the glutamate transporter gene, SLC1A1, were recently reported to be associated with OCD among males, but replication is required., Objectives: This study examines SLC1A1 as a candidate gene for OCD and explores gender influences. It was hypothesized that a significant association between SLC1A1 and OCD would be replicated in an independent sample of males but not females., Design: Family-based association candidate gene study., Setting: Participants were recruited from tertiary care OCD specialty clinics., Participants: OCD probands and their first degree relatives., Main Outcomes Measures: Association of OCD with genotypes of single nucleotide polymorphism (SNP) markers and related haplotypes., Results: Association between OCD and the three-marker haplotype rs12682807/ rs2072657/ rs301430, with overtransmission of A/T/T, was observed in both genders combined (global P = 0.0015) and in males (global P = 0.0031). Single-marker associations with OCD in the region (rs3780412 and rs2228622) demonstrated modest significance (permuted P = 0.045)., Conclusions: This study identifies a significant association between the SLC1A1 glutamate transporter gene and OCD in a haplotype overlapping with that recently reported., (2007 Wiley-Liss, Inc.)

ObjectiveTo identify heritable symptom-based subtypes of Tourette syndrome (TS).MethodsForty-nine motor and phonic tics were examined in 3,494 individuals (1,191 TS probands and 2,303 first-degree relatives). Item-level exploratory factor and latent class analyses (LCA) were used to identify tic-based subtypes. Heritabilities of the subtypes were estimated, and associations with clinical characteristics were examined.ResultsA 6-factor exploratory factor analysis model provided the best fit, which paralleled the somatotopic representation of the basal ganglia, distinguished simple from complex tics, and separated out socially disinhibited and compulsive tics. The 5-class LCA model best distinguished among the following groups: unaffected, simple tics, intermediate tics without social disinhibition, intermediate with social disinhibition, and high rates of all tic types. Across models, a phenotype characterized by high rates of social disinhibition emerged. This phenotype was associated with increased odds of comorbid psychiatric disorders, in particular, obsessive-compulsive disorder and attention-deficit/hyperactivity disorder, earlier age at TS onset, and increased tic severity. The heritability estimate for this phenotype based on the LCA was 0.53 (SE 0.08, p 1.7 × 10(-18)).ConclusionsExpanding on previous modeling approaches, a series of TS-related phenotypes, including one characterized by high rates of social disinhibition, were identified. These phenotypes were highly heritable and may reflect underlying biological networks more accurately than traditional diagnoses, thus potentially aiding future genetic, imaging, and treatment studies.

The direct estimation of heritability from genome-wide common variant data as implemented in the program Genome-wide Complex Trait Analysis (GCTA) has provided a means to quantify heritability attributable to all interrogated variants. We have quantified the variance in liability to disease explained by all SNPs for two phenotypically-related neurobehavioral disorders, obsessive-compulsive disorder (OCD) and Tourette Syndrome (TS), using GCTA. Our analysis yielded a heritability point estimate of 0.58 (se = 0.09, p = 5.64e-12) for TS, and 0.37 (se = 0.07, p = 1.5e-07) for OCD. In addition, we conducted multiple genomic partitioning analyses to identify genomic elements that concentrate this heritability. We examined genomic architectures of TS and OCD by chromosome, MAF bin, and functional annotations. In addition, we assessed heritability for early onset and adult onset OCD. Among other notable results, we found that SNPs with a minor allele frequency of less than 5% accounted for 21% of the TS heritability and 0% of the OCD heritability. Additionally, we identified a significant contribution to TS and OCD heritability by variants significantly associated with gene expression in two regions of the brain (parietal cortex and cerebellum) for which we had available expression quantitative trait loci (eQTLs). Finally we analyzed the genetic correlation between TS and OCD, revealing a genetic correlation of 0.41 (se = 0.15, p = 0.002). These results are very close to previous heritability estimates for TS and OCD based on twin and family studies, suggesting that very little, if any, heritability is truly missing (i.e., unassayed) from TS and OCD GWAS studies of common variation. The results also indicate that there is some genetic overlap between these two phenotypically-related neuropsychiatric disorders, but suggest that the two disorders have distinct genetic architectures.

Collecting phenotypic data necessary for genetic analyses of neuropsychiatric disorders is time consuming and costly. Development of web-based phenotype assessments would greatly improve the efficiency and cost-effectiveness of genetic research. However, evaluating the reliability of this approach compared to standard, in-depth clinical interviews is essential. The current study replicates and extends a preliminary report on the utility of a web-based screen for Tourette Syndrome (TS) and common comorbid diagnoses (obsessive compulsive disorder (OCD) and attention deficit/hyperactivity disorder (ADHD)). A subset of individuals who completed a web-based phenotyping assessment for a TS genetic study was invited to participate in semi-structured diagnostic clinical interviews. The data from these interviews were used to determine participants׳ diagnostic status for TS, OCD, and ADHD using best estimate procedures, which then served as the gold standard to compare diagnoses assigned using web-based screen data. The results show high rates of agreement for TS. Kappas for OCD and ADHD diagnoses were also high and together demonstrate the utility of this self-report data in comparison previous diagnoses from clinicians and dimensional assessment methods. [ABSTRACT FROM AUTHOR]

Objective: Although attention-deficit/hyperactivity disorder (ADHD) is frequently comorbid with Tourette's disorder (TD), it is unclear whether they have a common genetic etiology. Familial relationships between DSM-IV ADHD and TD are studied in TD+ADHD, TD-only (TD-ADHD), ADHD-only (ADHD-TD), and control groups.Method: Case-control, direct-interview family study of 692 relatives of 75 TD+ADHD, 74 TD-only, 41 ADHD-only, and 49 control probands collected between 1999 and 2004. Age-corrected prevalence rates, odds ratios, and predictors of TD, ADHD, and OCD among relatives are estimated from blinded best-estimate diagnoses using survival Kaplan-Meier and generalized estimating equation regression analyses.Results: In relatives of the TD-only group, although ADHD exceeded control rates (p=.03), ADHD-TD (p=.51) rates were not increased. In the ADHD-only group, TD was increased (p=.004) but TD-ADHD rates were not increased (p=.18). Comorbid ADHD+TD diagnoses in relatives were elevated in all case groups (pConclusions: TD and ADHD are not alternate phenotypes of a single underlying genetic cause. There is an increased risk of comorbid ADHD and TD in affected families, possibly reflecting some overlapping neurobiology or pathophysiology. [ABSTRACT FROM AUTHOR]