Genes , Economics , and Happiness Jan

Research on happiness has produced valuable insights into the sources of subjective well-being that are of importance to economics. A major finding from this literature is that people exhibit a “baseline” level of happiness that shows persistent strength over time. Here we explore the extent to which baseline happiness is influenced by genetic variation. Using data from Add Health, we employ a twin study design to show that genetic variation explains about 33% of the variation in happiness, and that the influence of genes varies by gender (women 26%, men 39%) and tends to rise with age. We also present evidence that variation in a specific gene predicts happiness. Individuals with a transcriptionally more efficient version of the serotonin transporter gene (SLC6A4 ) are significantly more likely to report higher levels of life satisfaction—having one or two alleles of the more efficient type raises the average likelihood of being very satisfied with one’s life by 8.5% and 17.3%, respectively. Finally, using data from an independent source (the Framingham Heart Study) we show that a linked single nucleotide polymorphism (rs2020933) in the SLC6A4 gene also predicts life satisfaction. These results are the first to identify a specific gene that may be associated with baseline levels of happiness. ∗Corresponding author: Jan-Emmanuel De Neve, London School of Economics, Houghton Street, London WC2A 2AE, United Kingdom (email: [email protected]). The authors thank Dan Benjamin, Chris Chabris, Chris Dawes, Pete Hatemi, David Laibson, Jaime Settle, Albert Vernon Smith, and Piero Stanig. This paper also benefited from comments at the Integrating Genetics and Social Sciences conference (Boulder, CO) and the UCL Institute of Neurology seminar. De Neve benefited from the generous hospitality of the Institute for Empirical Research in Economics (IEW) at the University of Zurich and the Center for Research in Economics, Management and the Arts (CREMA). Research was supported by National Institute on Aging grant P-01 AG-031093 and National Science Foundation grant SES-0719404 So our happiness depends on our genes and our experience (past and present). Any social reformer has to be mainly interested in the role of experience since that is all that we can change. But we will never understand that bit unless we understand the complete reality, and the complete reality includes a strong role for the genes. —Lord Richard Layard, Lionel Robbins Memorial Lecture, LSE. February 27, 2003.