Personality and well-being are genetically associated: Extending previous twin and molecular genetic studies

Neuroticism, extraversion, and conscientiousness are the most notable personality predictors of subjective well-being (SWB) in phenotypic and behavior genetic studies. We aim to quasi-replicate and extend previous findings. Using data from the German twin family panel TwinLife, we analyzed Big Five personality traits and life satisfaction of 3,080 twin pairs from three birth cohorts (born 2003/04, 1997/98, and 1990–93). Prior research has repeatedly provided evidence that genetic variance in personality traits largely explained genetic variance in SWB. Our results replicated this pattern with no significant unique genetic variance in life satisfaction. However, we found significant age cohort differences (e.g., only in ages 17–23 did genetic variance in openness partly explain genetic variance in life satisfaction). Furthermore, we tested personality–SWB associations using polygenic scores (PGSs) for Big Five personality traits and SWB. PGSs were calculated for N = 5,355 genotyped twin family members from the TwinSNPs study (age range 8–77). PGSs showed genetic association patterns similar to the twin study results, with neuroticism as the most robust predictor (up to 𝛽 = −.360) and openness showing near-null associations. Despite low overall explanatory power, phenotype prediction mirrored this as well (e.g., neuroticism PGSs predicted life satisfaction with up to 𝛽 = −.100).