Deconstructing the familiality of the emotive component of psychotic experiences in the general population.
OBJECTIVE
Genetic and environmental influences on variation in distress associated with subclinical psychotic experiences were examined.


METHODS
A total of 289 twin pairs filled in the Community Assessment of Psychic Experiences, a self-report instrument assessing subclinical positive and negative psychotic experiences and associated distress (distresspos and distressneg). Using structural equation modelling, univariate and bivariate models were fitted.


RESULTS
Univariate model fitting showed genetic and non-shared environmental influences on both distresspos and distressneg. Bivariate model fitting showed that 52% of the correlation between the two phenotypes (r=0.46) was because of shared genes and that non-shared environmental factors accounted for 48% of the correlation.


CONCLUSIONS
Liability to psychosis not only refers to the development of psychosis per se, but also to the liability to develop dysfunctional emotional appraisals. The emotive component of psychosis liability involves genetic transmission of a general, non-symptom-specific distress factor that may be a target for molecular genetic research.
Jacobs
N
N
Department of Psychiatry and Neuropsychology, South-Limburg Mental Health Research and Teaching Network, EURON, Maastricht University, Maastricht, the Netherlands.
Myin-Germeys
I
I
Derom
C
C
Vlietinck
R
R
van Os
J
J
D000293:Adolescent; D000328:Adult; D004644:Emotions; D004777:Environment; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D010375:Pedigree; D010641:Phenotype; D011618:Psychotic Disorders / Q000235:genetics* / Q000523:psychology*; D013315:Stress, Psychological