Posted: 05.10.2014 | by AMRA

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Are mindfulness-based interventions equally beneficial for everyone, or do some benefit more than others? If so, are their identifiable biological factors that play a significant role in determining who may benefit the most?

Bakker et al. [Translational Psychiatry] randomly assigned 126 participants with a past history of major depressive disorder but continuing residual symptoms to either an 8 week MBCT program or treatment-as-usual (TAU). Positive affect — the momentary experience of emotions such as happiness, cheerfulness, and satisfaction — was assessed prior to and after treatment by having participants rate their positive affect every time a special wristwatch beeped at unpredictable intervals over a six-day period.

Participants also submitted DNA samples which were assessed for single nucleotide polymorphisms — small variations in the DNA coding of genes that influence positive affect by modulating the brain’s dopamine, acetylcholine, and opioid receptor systems as well as the secretion of brain-derived neurogenic factor (BDNF), a protein that supports the growth and survival of neurons.

The authors had previously reported that MBCT significantly increased positive affect more than TAU in this cohort, but the purpose of this paper was to explore how genetics affected the participants’ ability to benefit from MBCT.

The researchers discovered that several genotypic variants had a significant impact on the degree to which MBCT increased the participants’ positive affect. Three of the genetic variants regulating opioid receptors and one variant regulating acetylcholine receptors significantly increased the degree to which MBCT increased positive affect.

On the other hand, there were variants of the genes controlling the dopamine receptors and the secretion of BDNF that decreased positive affect in the control group over time while leaving the MBCT group unaffected. Dopamine and opioid receptors play crucial roles in the brain’s reward circuitry, whereas acetylcholine receptors and BDNF have been implicated in disorders of deficient positive affect such as depression and alcoholism.

This study represents a significant step towards understanding who may benefit the most from clinical mindfulness interventions by identifying genetic influences that are associated with psychological changes.

Reference:

Bakker, J. M., Lieverse, R., Menne-Lothmann, C., Viechtbauer, W., Pishva, E., Kenis, G., . . . Wichers, M. (2014). Therapygenetics in mindfulness-based cognitive therapy: Do genes have an impact on therapy-induced change in real-life positive affective experiences? Translational Psychiatry, 4, e384.

[Link to abstract]