Specifically, the Val<sup>158</sup>Met polymorphism greatly alters COMT function and cognitive performance in both psychiatric disorders and healthy controls.
COMT is a known neuropsychiatric candidate gene, which contains a genotype variant (Val<sup>108/158</sup>Met) that affects protein function and has been found associated with several psychiatric disorders.
The present study appears to be the first comprehensive meta-analysis of COMT genetic association studies to cover all psychiatric disorders for which there were available data, published in any language, and with an emphasis on investigating disorder subtypes (defined clinically or by demographic or other variables).
The COMT Val<sup>158</sup>Met genotype and PTSD association persists after controlling for race (multivariable OR of 0.29, 95% CI [0.10-0.83]) and pre-existing psychiatric disorders/substance abuse (multivariable OR of 0.32, 95% CI [0.11-0.97]).
Further research with larger samples is needed to explore the interactions of the COMT gene rs4680 polymorphism and sex and psychiatric disorders on suicide attempts.
Among the genes in the deleted region, catechol-O-methyltransferase (COMT) has a particular relevance for psychiatric disorders: lower COMT enzymatic activity decreases the clearance of dopamine (DA), yielding higher levels of catecholamines in the central nervous system.
Since recent studies in patients affected by neurodegenerative and psychiatric disorders suggested a role of saitohin (STH) gene as a concurring factor in hypofrontality, we hypothesize that STH and COMT polymorphisms could have an additive effect on cognition in schizophrenia.
Additionally, these findings contribute to the growing literature on sex-specific effects of COMT on the predisposition to psychiatric disorders and personality traits.
Catechol O-methyltransferase (COMT) has been associated with aggression, attention deficit/hyperactivity disorder (ADHD), and other psychiatric disorders.
Although a polymorphism in this gene, COMTVal(158)Met, affects human behavior in response to stress little is known about its effect on dopaminergic activity associated with the human stress response, which may be of interest for stress-related psychiatric disorders such as psychosis.
One of its most widely studied variations comprises a common single nucleotide polymorphism (SNP), a valine-to-methionine substitution at codon 158 (COMTVal158Met), which has been associated with various cognitive phenotypes, psychiatric disorders and changes in brain activation and structure.
Many association studies have reported associations between the catechol-O-methyltransferase (COMT) gene and psychiatric disorders including major depression (MDD).
Many clinical and genomic association studies suggested that the catechol-O-methyltransferase (COMT) gene region was an important genetic locus for psychiatric disorders, because of the proposed relationship between its function in catecholaminergic neurotransmission and individual response to antidepressants, and vulnerability to psychiatric disorders.
The catechol-O-methyltransferase (COMT) Val158Met polymorphism moderates the effect of antenatal stress on childhood behavioural problems: longitudinal evidence across multiple ages.
On the other hand, preferential transmission of COMTrs4680 A allele and A-A haplotype (P<0.05) was observed specifically in male IID probands without any behavioral problem.
These preliminary data suggest that low COMT activity may affect dopamine levels in striatum in humans and this may have implications for understanding the contribution of COMT activity to psychiatric disorders.
To examine, in a sample of young psychiatric patients, (n = 157, mean age 17.01 years (SD = 3.6)) whether i) age at first cannabis use and age at emergence of psychiatric disorders are related and ii) such a relationship is modulated by the Val158Met polymorphism in the COMT gene.
The ValMet polymorphism of the COMT gene shows a complex relation to behavior problems, influencing conduct disorder and ADHD symptoms in opposite directions in a high-risk population.