Genetic and environmental bases of the interplay between magical ideation and personality.
Sub-threshold psychotic symptoms are quite commonly present in general population. Among these, Magical Ideation (MI) has been proved to be a valid predictor of psychosis. However, the genetic and environmental influences on the interplay between MI and personality have not fully been explored. A total of 534 adult twins from the population-based Italian Twin Register were assessed for MI using the MI Scale (MIS) and for personality with the temperament and character inventory (TCI). A Multivariate Cholesky model was applied with Mx statistical program. The best-fitting model showed that additive genetic and unshared environmental factors explain approximately the same proportion of variance in MI, whereas a less strong genetic influence on personality traits emerged. Relevant correlations between MI and specific personality traits (novelty seeking, cooperativeness, self-directedness, self-transcendence) were found, suggesting shared influences for MI and these traits. Both genetic and environmental factors explained these correlations, with genetic factors playing a predominant role. Moderate-to-substantial genetic effects on MI and personality were found. Shared genetic and environmental effects underlie the phenotypic correlation between MI (psychosis-proneness) and personality traits, i.e. self-directedness (negative association) and self-transcendence (positive association), potentially representing predictive markers of psychosis liability related to schizotypy and personality.
DISM, InterUniversity Center for Behavioural Neurosciences (ICBN), University of Udine, Udine, Italy; "E. Medea", UDGEE, Udine, Italy. Electronic address: paolo.brambilla@uniud.it.
Paolo
P
Brambilla
Genetic Epidemiology Unit, National Centre of Epidemiology, Surveillance and Health Promotion, Italian National Institute of Health, Rome, Italy.
Corrado
C
Fagnani
DISM, InterUniversity Center for Behavioural Neurosciences (ICBN), University of Udine, Udine, Italy.
Filippo
F
Cecchetto
Genetic Epidemiology Unit, National Centre of Epidemiology, Surveillance and Health Promotion, Italian National Institute of Health, Rome, Italy.
Emanuela
E
Medda
Department of Public Health and Community Medicine, Section of Psychiatry and Clinical Psychology, Inter-University Centre for Behavioural Neurosciences (ICBN), University of Verona, Verona, Italy.
Marcella
M
Bellani
Genetic Epidemiology Unit, National Centre of Epidemiology, Surveillance and Health Promotion, Italian National Institute of Health, Rome, Italy.
Miriam
M
Salemi
Mental Health Unit, National Centre of Epidemiology, Surveillance and Health Promotion, Italian National Institute of Health, Rome, Italy.
Angelo
A
Picardi
Genetic Epidemiology Unit, National Centre of Epidemiology, Surveillance and Health Promotion, Italian National Institute of Health, Rome, Italy.
Maria Antonietta
MA
Stazi
D000293:Adolescent; D000328:Adult; D000368:Aged; D002605:Character; D004200:Diseases in Twins / Q000209:etiology* / Q000235:genetics / Q000523:psychology; D005260:Female; D059647:Gene-Environment Interaction; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D010551:Personality; D010555:Personality Inventory; D010641:Phenotype; D011618:Psychotic Disorders / Q000209:etiology* / Q000235:genetics / Q000523:psychology; D012042:Registries; D012931:Social Environment; D013694:Temperament; D014427:Twins; D055815:Young Adult
Magical ideation; Psychosis; Schizotypy; Self-directedness; Self-transcendence; Temperament and character inventory; Twins