Sex Differences on Big Five Traits: Phenotypic differences (women higher in neuroticism, agreeableness, conscientiousness), but no genetic or environmental sex differences in any trait

Sex Differences in the Big Five Model Personality Traits: A Behavior Genetics Exploration. Susan C. South, 1, , Amber M. Jarnecke1, Colin E. Vize. Journal of Research in Personality, https://doi.org/10.1016/j.jrp.2018.03.002

Highlights
•    Mean level sex differences were found for Neuroticism, Agreeableness, and Conscientiousness (women higher on all)
•    No evidence of qualitative genetic differences between men and women on any of the Big Five traits.
•    No evidence of quantitative genetic or environmental differences between men and women on any of the Big Five traits.

Abstract: The importance of genetic influences for the Five Factor/Big Five Model (BFM) traits is well established. Relatively understudied, however, are the presence and magnitude of sex differences in genetic and environmental variance of these traits. The current study tested if men and women differ 1) qualitatively in the genetic mechanisms, or 2) quantitatively, on the genetic and environmental variance, contributing to BFM personality domains. Results from a nationally representative U.S. adult twin sample (N=973 pairs) supported phenotypic (i.e., mean level) sex differences in three of five personality traits (i.e., Neuroticism, Agreeableness, Conscientiousness) but did not support genetic or environmental sex differences in any trait.

Keywords: Personality; Sex differences; Behavior genetics; Twin