Because dopaminergic disturbance is thought to be involved in the development of bipolar disorder (BPD), it seems essential to investigate dopamine-related genes like the catechol-O-methyltransferase (COMT) gene, which are involved in dopamine metabolism, and the methylenetetrahydrofolate reductase (MTHFR) gene, which may affect COMT methylation and COMT function.
The negative effects of antipsychotics on cognitive functioning in bipolar disorder may be moderated by the COMT Val 108/158 Met genotype, with a negative effect of Val allele load.
A gene coexpression network was developed based on a mutual information approach including four candidate genes (NRG1, DISC1, BDNF and COMT) along with other coexpressing genes in unipolar disorder, bipolar disorder and schizophrenia.
Several studies have looked for a link between cocaine addiction and the genes of the dopaminergic system: the genes DRD2, COMT, SLC6A3 (coding for the dopamine transporter DAT) and DBH (coding for the dopamine beta hydroxylase) but unfortunately very few well established results.
In this issue of Neuropsychopharmacology, several studies are presented supporting a role for COMT as a factor in cocaine addiction, brain reward activation, response to tolcapone, distractibility in ADHD, and fMRI bold response.
In this study we examined the expression levels of COMT mRNA using quantitative RT-PCR in 60 post mortem cerebellum samples derived from individuals with schizophrenia, bipolar disorder, depression, and no history of psychopathology.
The present study investigated the effects of familial risk for depression and the 5-HTTLPR and COMT Val158Met polymorphisms, which have been associated with risk for depression, on biases in endorsement of and memory for positive and negative adjectives.
The relationship between catechol-O-methyltransferase gene Val158Met (COMT) polymorphism and premorbid cannabis use in Turkish male patients with schizophrenia.
The present study investigated the effects of familial risk for depression and the 5-HTTLPR and COMT Val158Met polymorphisms, which have been associated with risk for depression, on biases in endorsement of and memory for positive and negative adjectives.
The results showed that the COMT polymorphism influenced the volume of the bilateral ventral caudate nucleus in both groups, but in an opposite direction: more copies of val allele led to lesser volume in chronic cannabis users and more volume in controls.