There is a fascinating article in the most recent Psychological Science. It studies how much influence our genes have on our subjective well being (e.g., how happy we are with our lives). Alexander Weiss (University of Edinburgh), Timothy Bates, and Michelle Luciano (Queensland Institute of Medical Research, Brisbane) investigated this question using a sample of identical and fraternal twins in the MacArthur Foundation Survey of Midlife Development.

The looked at how similar the twins were to each other in their personalities (extroversion, agreeableness, conscientiousness, neuroticism, and openness to experience) and subjective well being. This is a method popular in behavioral genetics. Identical twins share all of their genes and fraternal twins share only half of their genes (on average). If they are raised together then both kinds of twins were in the same environment. So any differences between how similar identical and fraternal twins must be due to differences in shared genes.

The authors found that there was a substantial genetic component in happiness (subjective well being) but that this component was accounted for by the genetic component of personality. That is, we are generally happy or unhappy because of our personality, and our personality is, in part determined, by our genes.

What does this mean? Well, some have proposed that everyone has a set point in how happy they can be, and this is genetically determined. If this is true, you can become more or less happy with changes in the environment, but over the long haul you will return to your set point of happiness. This explains why individuals are happier soon after winning the lottery, but soon after return to how happy they were before they won the lottery.

But there are also some questions about this methodology. For example, we know that identical twins are treated the same more often than fraternal twins, sometimes even being mistaken for each other. So the shared environment of fraternal twins may not be as big as that of identical twins. And other work has shown that there are ways of changing how happy you are over the long haul.

No doubt there is a genetic component to happiness, but how big that component is and how much it affects life day to day remains to be seen.

Further Reading:

For another article on this study:

Genes Hold The Key To How Happy We Are, Scientists Say

You can find the original article at:

Weiss, A., Bates, T. C., Luciano, M. (2008). Happiness is a personal(ity) thing: The genetics of personality and well-being in a representative sample. Psychological Science, 19, 205-210.

For some other interesting reading you can check out this book by one of the worlds leading experts on happiness, Sonja Lyubomirsky.

Lyubomirsky, S. (2007). The How of Happiness. Penguin Press.