Let’s just get this out of the way first thing: Researchers have not found “the happiness gene.” There’s no one single piece of DNA that determines to any meaningful degree who lives out their days in misery and who’s a relentless ray of sunshine.
If nuance is your thing, though, a recent study in the journal Nature Genetics has hit on something interesting: A team of 181 scientists from around the world has identified a few specific genetic components that may influence how people experience happiness — a finding, they’re careful to note, that offers hints for future research more than any definitive answers about where well-being comes from.
The study drew on a massive trove of past research, analyzing the previously collected genetic information of roughly 298,000 people. When they measured the genomes against self-reported measures of well-being and life satisfaction, the study authors were able to link three places on the genome to differences in happiness levels — even after controlling for a handful of health issues that might negatively affect happiness, including smoking status and heart disease. (They also found two genetic variants linked to a person’s likelihood of experiencing depression symptoms, and 11 connected to neuroticism.)
The findings add more brushstrokes to the overall picture of human happiness, but on their own, the three gene variants “explain a tiny, tiny part of the variance in well-being. Less than one percent,” says study co-author Meike Bartels, a genetics professor at Vrije Universiteit Amsterdam. “There’s a lot that’s unknown about our DNA and our gene expression. These variants have such a tiny effect, we needed 300,000 individuals just to find these three. If we doubled the sample size, we might find another 50.” And regardless of number, genetic variants on their own can only provide so much information, she says: “In the end, the differences between people are the result of the interplay between genes and environment.”
In a statement, Bartels called the study “both a milestone and a new beginning: A milestone because we are now certain that there is a genetic aspect to happiness and a new beginning because the three variants that we know are involved account for only a small fraction of the differences between human beings.” The question isn’t whether happiness is a product of nature versus nurture, in other words, but how the two work in tandem in all their various complicated ways to determine our well-being.