Big Five Personality and CTRA gene expression: Lack of association in a midlife sample of US adults (MIDUS-Refresher).

A previous study found that Extraversion and Conscientiousness were associated with increased and decreased expression of a pre-specified set of pro-inflammatory indicator genes. The present study aimed to replicate these findings in a sample of adults from the Refresher Cohort of the Study of Midlife in the United States (MIDUS). Analysis of gene expression composite scores and generalized linear models that took into account the heterogeneity and non-independence of RNA expression across different genes found no significant associations between the pro-inflammatory indicator gene set and the Big Five domains of personality. In addition, there was no significant association between a pre-specified antiviral indicator gene set and the Big Five domains. These findings suggest that relations between Big Five personality and expression of these two immune response indicator gene sets do not consistently appear across samples and may be context-dependent in ways that remain to be elucidated.