The relationship between childhood abuse and dissociation. Is it influenced by catechol-O-methyltransferase (COMT) activity?
Dissociation is a failure of perceptual, memorial and emotional integration that is associated with a variety of psychiatric disorders. Dissociative processes are usually attributed to the sequelae of childhood trauma although there are data to suggest that genetic influences are also important. Bipolar disorder (BD), a condition with a strong genetic basis, has also been associated with early psychological trauma. Since childhood trauma is a risk factor for both BD and dissociation, we tested for potential gene-childhood abuse interactions on dissociation in a pilot sample of BD probands and their affected and unaffected relatives (n=178). Dissociation was measured with the Dissociative Experiences Scale (DES II) and childhood maltreatment with the Childhood Trauma Questionnaire (CTQ). The BD and recurrent unipolar depression (MDE-R) groups showed higher levels of self-reported abuse and dissociation than their unaffected relatives. The low-activity Met allele of the Val66Met polymorphism of the brain-derived neurotrophic factor (BDNF) gene was associated with lower levels of self-reported dissociation. Further, the functional catechol-O-methyltransferase (COMT) Val158Met polymorphism interacted significantly with total CTQ abuse scores to impact perceived dissociation. The Val/Val genotype was associated with increasing levels of dissociation in participants exposed to higher levels of childhood trauma. The opposite was observed in people with Met/Met genotypes who displayed decreased dissociation with increasing self-reported childhood trauma. The current findings support the involvement of the COMT Val158Met polymorphism in mediating the relationship between trauma and psychopathology.
Savitz
Jonathan B
JB
MRC/UCT Human Genetics Research Unit, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa. savitzj@mail.nih.gov
van der Merwe
Lize
L
Newman
Timothy K
TK
Solms
Mark
M
Stein
Dan J
DJ
Ramesar
Rajkumar S
RS
D000328:Adult; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D002648:Child; D002649:Child Abuse / Q000523:psychology*; D004213:Dissociative Disorders / Q000201:enzymology / Q000235:genetics* / Q000523:psychology; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D010865:Pilot Projects; D011110:Polymorphism, Genetic; D011594:Psychometrics; D012307:Risk Factors; D011795:Surveys and Questionnaires
D019208:Brain-Derived Neurotrophic Factor; D002394:Catechol O-Methyltransferase