Why are some people happier than others, even if they live in the same country under more or less similar circumstances? Knowing why some people feel better about their lives than others can provide researchers with clues about how best to help those most in need. Genetically informed research can provide valuable clues, such as twin and family studies.
One such study worked with data based on four types of twin pairs: genetically identical and fraternal twins who grew up together and identical and fraternal twins who were separated shortly after birth. The research team has brought the separated twins together and assessed their well-being. They’ve found out that twins who were reared apart became more similar in the context of their well-being than fraternal twins who grew up together. This finding was the first, but a very powerful, indication that genetic differences between people are a source of differences in happiness. Since this foundational study, dozens of other twin-family studies have yielded similar results. They’ve all shown that genetic and environmental influences are important for variation in well-being among individuals living in the same society.
Studies based on European ancestry samples reveal that genetic differences between people account for approximately 40% of the differences in happiness, while the remaining variance is accounted for by environmental influences unique to an individual. Another key finding is that the importance of genetic influences is not fixed from birth but can change throughout the lifespan and in response to current environmental conditions.
It is safe to say that estimates of the importance of genetic and environmental influences are just the starting point for much further research that explores the intricate ways in which genetic and environmental propensities play out across a lifespan and in response to changing experiences and exposures. And there is an added complexity: not only are there likely to be interactions between genetic and environmental influences, but our environmental experiences and exposures are also likely to be actively shaped by us and the people we surround ourselves with.
Given the robust heritability estimate of 40% and the progress in molecular genetics, it’s important to go beyond an estimate based on twin-family designs to search for differences in the human genome to explain differences in well-being. Better knowledge of the link between the human genome and well-being could improve understanding of the underlying biological processes to support improved prevention and intervention programs. This might even permit personalized well-being interventions.
An obvious organ to study to explain differences in well-being among individuals is the brain, a key player in mood and emotion regulation. Besides the brain, many human body processes could be important in explaining individual differences in happiness and well-being among individuals. For example, differences in neurotransmitter levels, hormone levels, and immune parameter activity have been linked to well-being.
In conclusion, genetic studies are likely to be a gamechanger for studying happiness and well-being and to have a ground-breaking impact on intervention models and strategies. Currently, such models and strategies are in their early stages. Further studies into this arena will illuminate how happiness and health may be formed by social selection or causation and directly inform us on creating beneficial neighborhoods that prevent manifestations of genetic risk and promote opportunities for different individuals and population groups.
Keep Reading about the World Happiness Report 2022 findings. Insights From the First Global Survey of Balance and Harmony