Happiness is in our genes
A recent Japanese study has found that we can be genetically predisposed to happiness.
Scientists from Universities in Nagoya, Aichi & Mie, and from Kizawa Memorial Hospital, evaluated 198 healthy volunteers to determine their subjective happiness level. Each then underwent a genetic test to determine whether they carry a genetic mutation associated with their Cannabinoid Receptor 1 (CB1) gene. The volunteers were then asked to watch both neutral and positive movies, and the participants noted their mood states after each film.
The researchers divided feelings of happiness between temporary feelings of pleasure, and a relatively stable sense of being content. It was discovered that those with the mutation are more sensitive to positive stimuli, and experience both these aspects of happiness to a significantly greater degree.
Cannabinoid receptors are involved in several physiological processes including appetite, nociception, mood, and memory. CB1 is specifically responsible for the brain’s ‘reward system’, the process in which we are rewarded with pleasurable feelings in response to actions or stimuli. It is believed that the activation of CB1 induces a dopamine release in the striatum, a subcortical part of the brain, causing a pleasurable feeling on a chemical level.
A previous study has already shown that those carrying the mutation – a ‘cytosine to thymine’ genotype as opposed to ‘thymine to thymine’ genotype – reacted to a greater degree when shown other peoples’ happy faces. The researchers theorised that the presence of this mutation could also have an impact on subjective happiness.
It was found that those with the ‘cytosine to thymine’ mutation were more likely to have an active CB1, resulting in a more pleasurable outlook and a higher magnitude pleasure response when they perceive positive events.
The scientists also found that both age and weight made little difference to the impact of the mutation. In all experiments those participants with the ‘cytosine to thymine’ genotype always reported a higher level of positivity or happiness in response to what they were being shown.
It is believed that a number of personality traits are linked to our genes. A past neuroimaging study showed that optimism was linked to the response of the cerebral cortex to positive stimuli, a part of the brain which engages during emotional conflict resolution and various positive emotional states. This study shows that the cerebral cortex is also indirectly affected by the ‘cytosine to thymine’ mutation, suggesting this gene is linked to multiple parts of the brain and multiple personality traits.
It’s thought that this study will greatly impact the way we view our feelings of happiness and raise many interesting questions about the applications of this discovery. For example, if a genetic test can establish a person’s sensitivity to happiness, and gene therapy is able to increase this sensitivity to give that individual a happier life; what would the negative consequences be? Could this be a viable treatment for mental disorders such as depression?
Aside from the curative potential of such genetic therapies, there are clearly ethical issues with ‘personality surgery’ which must be addressed should we gain the ability to alter our traits.
The source research for this article can be found here.