Happiness in Behaviour Genetics: An Update on Heritability and Changeability

In this paper we summarize recent behaviour genetic findings on happiness measured as life satisfaction (LS) and subjective wellbeing (SWB) and discuss important implications pertaining to stability and change, including the potential of individual and societal interventions. Broadly speaking, two main research strategies explore genetic and environmental influences on happiness, including quantitative and molecular genetics. Whereas molecular genetics seeks to trace the causal pathways from specific DNA variants, quantitative genetics estimates the magnitude of overall genetic and environmental influences without specifying actual DNA sequences and usually without specifying specific environmental circumstances. Molecular genetic studies have entered the happiness arena, but have shown mixed results. Most replicated findings are therefore based on quantitative genetics and derived from twin and family studies decomposing variation and co-variation into genetic, shared, and non-shared environmental sources. Recent meta-analyses of such studies report genetic influences (i.e., heritability) to account for 32–40 % of the variation in overall happiness (i.e., SWB, LS), and indicate that heritability varies across populations, subgroups, contexts and/or constructs. When exploring stable SWB levels, heritability is reported in the 70–80 % range, whereas momentary positive affect is often entirely situational. Happiness is thus heritable, stable, variable and changeable. What do these findings imply? Can happiness be raised as a platform in individuals and societies? We suggest that individual and societal interventions that target causal pathways and address both amplifying and compensatory processes (i.e., focus on developing strengths and mitigating risks)—thus providing for positive gene-environment matchmaking, are likely to be effective and longer lasting.