The Role of 5-HTTLPR and MAOA in Moderating the Association Between Environment and Well-being

Background: 5-HTTLPR and MAOA are traditionally considered to confer risk for negative outcome in the context of the gene-environment interaction. The aim of the current study was to further investigate this interaction in the context of a beneficial environment. Methods: Two hundred and one college students provided saliva samples for DNA extraction and completed self-reported questionnaires measuring attachment, perceived social support and experience of life events. ANOVA, Pearson correlation and linear regression analysis were used to examine the correlation between these explaining variables and an outcome measure of well-being. Results: Full data were available for one hundred and sixty-six subjects. We found a significant interaction between genotype and environment in their effect on happiness. Only individuals with the 5-HTTLPR short allele(s) or within MAOA intermediate and low activity genetic groups were happier when they perceived higher support from their friends. Conclusions: Even though the sample is small these results show that genetic polymorphisms confer not only resilience or vulnerability to stress, but also provide their carriers with sensitivity to a beneficial environment.