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BackgroundObsessive-compulsive disorder (OCD) has a complex etiology involving both genetic and environmental factors. However, the genetic causes of OCD are largely unknown, despite the identification of several promising candidate genes and linkage regions.MethodsOur objective was to conduct genetic linkage studies of the type of OCD thought to have the strongest genetic etiology (i.e., childhood-onset OCD), in 33 Caucasian families with ≥2 childhood-onset OCD-affected individuals from the United States (n = 245 individuals with genotype data). Parametric and nonparametric genome-wide linkage analyses were conducted with Morgan and Merlin in these families using a selected panel of single nucleotide repeat polymorphisms from the Illumina 610-Quad Bead Chip. The initial analyses were followed by fine-mapping analyses in genomic regions with initial heterogeneity logarithm of odds (HLOD) scores of ≥2.0.ResultsWe identified five areas of interest (HLOD score ≥2) on chromosomes 1p36, 2p14, 5q13, 6p25, and 10p13. The strongest result was on chromosome 1p36.33-p36.32 (HLOD = 3.77, suggestive evidence for linkage after fine mapping). At this location, several of the families showed haplotypes co-segregating with OCD.ConclusionsThe results of this study represent the strongest linkage finding for OCD in a primary analysis to date and suggest that chromosome 1p36, and possibly several other genomic regions, may harbor susceptibility loci for OCD. Multiple brain-expressed genes lie under the primary linkage peak (approximately 4 megabases in size). Follow-up studies, including replication in additional samples and targeted sequencing of the areas of interest, are needed to confirm these findings and to identify specific OCD risk variants.

Despite considerable heterogeneity in the precise symptoms experienced across patient populations, there is growing realization that common neurobiological processes may contribute to obsessive compulsive disorder (OCD) vulnerability and its persistence. [...]

Compulsivity has potential transdiagnostic relevance to a range of psychiatric disorders, but it has not been well-characterized and there are few existing measures available for measuring the construct across clinical and nonclinical samples that have been validated at large population scale. We aimed to characterize the multidimensional latent structure of self-reported compulsivity in a population-based sample of British children and adults (N = 182,145) using the Cambridge–Chicago Compulsivity Trait Scale (CHI-T). Exploratory structural equation modeling provided evidence for a correlated two-factor model consisting of (a) Perfectionism and (b) Reward Drive dimensions. Evidence was obtained for discriminant validity in relation to the big five personality dimensions and acceptable test–retest reliability. The CHI-T, here validated at extremely large scale, is suitable for use in studies seeking to understand the correlates and basis of compulsivity in clinical and nonclinical participants. We provide extensive normative data to facilitate interpretation in future studies. [ABSTRACT FROM AUTHOR]

The Structured Clinical Interview for Gambling Disorder (SCI-GD) has the potential to bridge a diagnostic clinical gap, but psychometric evaluations have been scarce, in particular in relation to self-reported diagnostic criteria. This study analyzed existing data, including Swedish gamblers (N = 204) from treatment- and help-seeking contexts, self-help groups, and the general population, who were interviewed with the SCI-GD and completed self-report measures. The results indicated that fewer individuals fulfilled the diagnostic criteria for gambling disorder (GD) with the SCI-GD (n = 110, 54%), compared to a self-report Diagnostic and Statistical Manual of Mental Disorders:5th Edition (DSM-5) questionnaire on GD (n = 145, 71%; p <.001). Agreement between interviews and self-reported criteria was generally low (Fleiss kappa range: 0.31–0.52; r range: 0.35–0.55). A Rasch analysis showed that specific diagnostic criteria varied in difficulty, indicating a general pattern of higher item difficulty for the SCI-GD compared to self-reported DSM-5 criteria. Both the SCI-GD and the self-reported DSM-5 criteria performed well in terms of internal consistency, convergent, and discriminant validity. We conclude that the SCI-GD is a reliable and valid diagnostic tool to assess GD among individuals with various gambling behavior patterns. Further research-related and clinical implications are discussed. [ABSTRACT FROM AUTHOR]