Predicting post-traumatic stress disorder in veterans: interaction of traumatic load with COMT gene variation.
BACKGROUND
Because post-traumatic stress disorder (PTSD) by definition can occur only after exposure to a traumatic event, military veterans who are at high risk for trauma exposure are a particularly relevant population for studying the interaction of trauma with genetic factors that may predispose for the disorder. A number of studies have implicated specific genes as possible risk factors in developing PTSD, including the catechol-O-methyltransferase gene (COMT).


METHODS
Data from Iraq War veterans (n = 236) were used to examine the interaction between COMT and traumatic experiences in predicting later development of PTSD symptoms. Subjects were assessed for exposure to traumatic events both before and during deployment.


RESULTS
The interaction between trauma load and COMT was a significant predictor of PTSD symptoms. Those with the heterozygous genotype (Val/Met) showed fewer symptoms associated with trauma exposure compared to those with either homozygous genotype. This interaction remained significant after controlling for other risk factors for PTSD, including personality dimensions of Internalizing and Externalizing.


CONCLUSIONS
COMT genotype affects risk for development of PTSD symptoms following exposure to trauma.
University of Minnesota Psychology Department, USA.
Rachel
R
Clark
Colin G
CG
DeYoung
Scott R
SR
Sponheim
Tricia L
TL
Bender
Melissa A
MA
Polusny
Christopher R
CR
Erbes
Paul A
PA
Arbisi
D000328:Adult; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008016:Life Change Events; D008137:Longitudinal Studies; D008297:Male; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011569:Psychiatric Status Rating Scales; D012044:Regression Analysis; D012307:Risk Factors; D018709:Statistics, Nonparametric; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis* / Q000235:genetics*; D015599:Trauma Severity Indices; D014728:Veterans; D055815:Young Adult
D002394:Catechol O-Methyltransferase
COMT; GxE interaction; Internalizing; PTSD; Veterans