Article

Obsessive-compulsive disorder, tics and anxiety in 6-year-old twins

Institute of Psychiatry, Kings College London, UK.
Psychological Medicine (Impact Factor: 5.43). 02/2007; 37(1):39-48. DOI: 10.1017/S0033291706008816
Source: PubMed

ABSTRACT Previous reports of genetic influences on obsessive-compulsive disorder (OCD) symptoms have suggested moderate heritability. Family history studies of co-morbidity have found familial aggregation with tics, especially for early-onset OCD, and familial aggregation with anxiety disorders.
Heritability of OCD and familial aggregation of OCD, tics and anxiety disorders were investigated in a community sample of 6-year-old twins using a two-phase design in which 4662 twin pairs were sampled and 854 pairs were assessed in the second phase by maternal-informant diagnostic interview using DSM-IV criteria.
In the multivariate model combined additive genetic and common environmental effects were estimated as 47% for sub-threshold OCD, and the model was unable to distinguish these sources of familial aggregation. There were strong familial aggregations between sub-threshold OCD and tics and between sub-threshold OCD and other anxiety disorders (80% and 97% respectively), although again specific sources could not be distinguished.
The findings are consistent with the hypothesis of a tic-related early-onset OCD phenotype, but also with the hypothesis of an anxiety-related early-onset OCD phenotype.

Download full-text

Full-text

Available from: Sean Perrin, Jul 03, 2015
0 Followers
 · 
122 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The contribution of genetic factors to obsessive-compulsive (OC) symptoms has not been examined using a large population-based sample of adults. Furthermore, the extent to which there are qualitative and quantitative differences in genetic architecture between men and women with OC symptoms has not been elucidated. We obtained the Young Adult Self Report Obsessive-Compulsive Scale (YASR-OCS) from a group of 5893 monozygotic (MZ) and dizygotic (DZ) twins, and 1304 additional siblings from the population-based Netherlands Twin Register. Structural equation modelling was used to decompose the variation in OC behaviour into genetic and environmental components and analyse quantitative and qualitative sex differences. Familial resemblance was the same for DZ twins and non-twin siblings, which means that there was no evidence for a special twin environment. The same genetic risk factors for OC behaviour were expressed in men and women. Depending on the choice of fit index, we found small (39% for men and 50% for women) or no sex differences (47% for both men and women) in heritability. The remaining variance in liability was due to individual-specific environment. OC behaviour showed a moderate heritability. At most, small quantitative sex differences were found in the genetic architecture of OC behaviour, and no qualitative sex differences.
    Psychological Medicine 12/2007; 37(11):1635-44. DOI:10.1017/S0033291707000980 · 5.43 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Oxygen, sulphide and nutrient (ammonia, nitrite and phosphate) uptake of Anodontia edentula was measured. Oxygen and sulphide were measured from sealed containers provided with 1 l fresh mangrove mud (sulphide source) and seawater (oxygen source) with two treatments (with and without clam) at 16 replicates each. Oxygen, sulphide and other parameters were measured at days 1 (initial), 3 and 5 (final). Nutrients were measured from containers filled with 1.5 l wastewater from a milkfish broodstock tank with two treatments (with and without clam) at eight replicates each. Ammonia, NO2 and P04 were measured at days 0 (initial) 3, 6, 9 and 12 (final). Results showed significantly decreasing oxygen and sulphide concentrations in treatment with clams (ANOVA, p < 0.001). A significantly higher ammonia concentration (ANOVA, p < 0.05) was observed in treatment with clams while no significant difference was observed in nitrite and phosphate between the two treatments. A decreasing ammonia and an increasing nitrite trend was also observed in both treatments starting at day 3.
    Marine Pollution Bulletin 12/2001; 42(11):1133-8. DOI:10.1016/S0025-326X(01)00113-8 · 2.79 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: There is considerable evidence that genetic determinants play a major role in the etiology of anxiety. Investigations into susceptibility genes for anxiety are well underway, particularly for panic disorder and obsessive-compulsive disorder and more broadly defined anxiety-related traits, such as neuroticism and harm avoidance. This review will discuss some of the core issues related to diagnosis and molecular genetic methodology, followed by a review of recent molecular genetic findings for anxiety. The authors will attempt to highlight the numerous convergent and exciting findings. Given the rapid acceleration in knowledge of the human genome, a more definitive understanding of the genetic roots of these complex conditions may be anticipated in the relatively near future.
    Current Psychiatry Reports 09/2004; 6(4):243-54. DOI:10.1007/s11920-004-0073-1 · 3.05 Impact Factor