The molecular genetics of life satisfaction: Extending findings from a recent genome-wide association study and examining the role of the serotonin transporter

In a recent genome-wide association study (GWAS), three polymorphisms (rs3756290, RAPGEF6; rs2075677, CSE1L; rs4958581, NMUR2) were suggested as potentially being related to subjective-well-being and life satisfaction. Additionally, associations between the 5-HTTLPR polymorphism (serotonin transporter) and subjective well-being have been reported in other previous studies. In the current study, we therefore sought to further investigate the findings of the GWAS and examine the association between 5-HTTLPR and subjective well-being. A total of 1174 participants (821 females) were recruited and asked to provide information on their demographics, life satisfaction, and positive affect. All participants provided a genetic sample. We found associations between one SNP derived from the GWAS (rs4958581, NMUR2) and life satisfaction. We also replicated findings involving 5-HTTLPR and life satisfaction, but only for the housing, leisure and family life satisfaction variables, and not for overall life satisfaction or positive affect. Our study underlines that research investigating complex traits in the field of behavioral genetics is challenging due to their (a) pleiotropic and (b) polygenic effects, resulting in tiny effect sizes of each marker investigated. The current study also highlights the importance of investigating genetic markers of distinct areas of life satisfaction.