4XUE, 3A7E, 3BWM, 3BWY, 4PYI, 4PYJ, 4PYK, 4XUC, 4XUD131212846ENSG00000093010ENSMUSG00000000326P21964O88587NM_000754NM_001135161NM_001135162NM_007310NM_001362828NM_001111062NM_001111063NM_007744NP_000745NP_001128633NP_001128634NP_009294NP_001349757NP_001104532NP_001104533NP_031770Catechol-O-methyltransferase (COMT; EC 2.1.1.6) is one of several enzymes that degrade catecholamines (neurotransmitters such as dopamine, epinephrine, and norepinephrine), catecholestrogens, and various drugs and substances having a catechol structure.

[25][26][27] A functional single-nucleotide polymorphism (a common normal variant) of the gene for catechol-O-methyltransferase results in a valine to methionine mutation at position 158 (Val158Met) rs4680.

[29] The lower rates of catabolism for the Met allele results in higher synaptic dopamine levels following neurotransmitter release, ultimately increasing dopaminergic stimulation of the postsynaptic neuron.

[35] A more recent study cast doubt on the proposed connection between this gene and any alleged casual effect of cannabis on schizophrenia development.

[36] A non-synonymous single-nucleotide polymorphism rs4680 was found to be associated with depressed factor of Positive and Negative Syndrome Scale(PANSS) and efficiency of emotion in schizophrenia subjects.

[37] It is increasingly recognised that allelic variation at the COMT gene are also relevant for emotional processing, as they seem to influence the interaction between prefrontal and limbic regions.

Research conducted at the Section of Neurobiology of Psychosis, Institute of Psychiatry, King's College London has demonstrated an effect of COMT both in patients with bipolar disorder and in their relatives,[38] but these findings have not been replicated so far.

When 621 women were measured with experience sample monitoring, which is similar to mood assessment as response to beeping watch, the met/met form confers double the subjective mental sensation of well-being from a wide variety of daily events.

Genetic variation with functional impact on cortical dopamine tone has a strong influence on reward experience in the flow of daily life.