The MAO-A genotype does not modulate resting brain metabolism in adults

Medical Department, Brookhaven National Laboratory, Upton, New York 11973, United States.
Psychiatry Research (Impact Factor: 2.47). 09/2008; 164(1):73-6. DOI: 10.1016/j.pscychresns.2007.12.010
Source: PubMed


Variation in the monoamine-oxidase-A (MAO-A) gene has been associated with volumetric changes in corticolimbic regions with differences in their response to relevant emotional tasks. Here we show no changes in baseline regional brain metabolism as a function of genotype indicating that, unchallenged, corticolimbic activity is not modulated by the MAO-A genotype.

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    • "In summary, these fMRI studies clearly show that specific brain regions, previously implicated in emotion processing, and behaviour were functionally and anatomically affected by genetic variation in the genes for MAOA and 5HTT, indicating a potential effect of variable serotonin levels on these structures. The fact that levels and activity of the MAOA and 5HTT in the adult brain are poorly associated with genotype (19–26) argues for a developmental effect of the functional polymorphisms on these neurocircuits by regulating embryonic/foetal serotonin levels. This interpretation is supported by recent studies showing disturbances to the same corticolimbic structures resulting from absence of the serotonin transporter during development (64,65) and also from the identification of non-serotonergic neurons in various limbic areas, transiently expressing the serotonin transporter (66). "
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