Effects of interactions between variation in dopaminergic genes, traumatic life events, and anomalous self-experiences on psychosis proneness: Results from a cross-sectional study in a nonclinical sample

• Published in: European psychiatry Vol. 63; no. 1; p. e104
• Main Authors: Frydecka, Dorota, Kotowicz, Kamila, Gawęda, Łukasz, Prochwicz, Katarzyna, Kłosowska, Joanna, Rymaszewska, Joanna, Samochowiec, Agnieszka, Samochowiec, Jerzy, Podwalski, Piotr, Pawlak-Adamska, Edyta, Szmida, Elżbieta, Cechnicki, Andrzej, Misiak, Błażej
• Format: Journal Article
• Language: English
• Published: England Cambridge University Press 20.11.2020
• Subjects: Alleles; Anomalous self-experiences; Catechol O-Methyltransferase - metabolism; childhood trauma; Cross-Sectional Studies; Dopamine - metabolism; Female; Gene-Environment Interaction; Humans; Male; Poland; Polymorphism, Genetic; psychosis; Psychotic Disorders - genetics; Psychotic Disorders - metabolism; Receptors, Dopamine D2 - metabolism; schizophrenia; stress; Surveys and Questionnaires; Young Adult; Poland; childhood trauma; stress; Anomalous self-experiences; schizophrenia; psychosis
• ISSN: 0924-9338; 1778-3585
• DOI: 10.1192/j.eurpsy.2020.103

There is a growing number of studies showing interactions between genetic polymorphisms associated with dopaminergic neurotransmission and traumatic life events (TLEs) on a risk of psychotic-like experiences (PLEs). Anomalous self-experiences (ASEs) have been associated both with TLEs as well as with PLEs. However, it remains unknown what is the role of ASEs in the complexity of gene-environment interactions on the emergence of PLEs. We included 445 young adults-university students from three big cities in Poland. We used the Traumatic Events Checklist to assess TLEs, the Inventory of Psychotic-Like anomalous self-experiences in order to measure ASEs, and the Prodromal Questionnaire (PQ16) to record the level of PLEs. The following gene polymorphisms, related to dopaminergic neurotransmission, were determined: the catechol-O-methyltransferase (COMT) rs4680 polymorphism, the dopamine D2 receptor (DRD2) rs6277 polymorphism, and the dopamine transporter 1 (DAT1) rs28363170 polymorphism. There was a significant effect of the interaction between the DAT1 polymorphism, a severity of ASEs, and a history of TLEs on the level of PLEs. Among the DAT1 10R/10R homozygotes with low level of ASEs, a severity of PLEs was significantly higher in individuals with a history of any TLEs. Higher scores of the PQ16 were associated with a greater severity of ASEs both in the DAT1 9R allele carriers and the DAT1 10R/10R homozygotes. Our findings imply that genetic liability related to aberrant dopamine transport might impact the association between TLEs and PLEs in subjects with high levels of ASEs.