This research is part of the Twin Interdisciplinary Neuroticism Study (TWINS) in cooperation with the Study of Allostatic Load as a Unifying Theme (SALUT). TWINS was supported by the Netherlands Organisation for Health Research and Development (ZonMw 904-57-130) and the UK–Netherlands Partnership Program in Science (BR 56-481 and BR 96-229), which is jointly run and financed by the British Council and the Netherlands Organization for Scientific Research (NWO). SALUT is a collaboration between various departments of the University Medical Center Groningen, The Netherlands. SALUT is financially supported by the NWO (Pionier 900-00-002 and VENI 916-56-064) and by the participating centers.
Neuroticism and Morning Cortisol Secretion: Both Heritable, But No Shared Genetic Influences
Article first published online: 11 AUG 2009
© 2009, Copyright the Authors. Journal compilation © 2009, Wiley Periodicals, Inc.
Journal of Personality
Volume 77, Issue 5, pages 1561–1576, October 2009
How to Cite
Riese, H., Rijsdijk, F. V., Rosmalen, J. G. M., Snieder, H. and Ormel, J. (2009), Neuroticism and Morning Cortisol Secretion: Both Heritable, But No Shared Genetic Influences. Journal of Personality, 77: 1561–1576. doi: 10.1111/j.1467-6494.2009.00592.x
- Issue published online: 1 SEP 2009
- Article first published online: 11 AUG 2009
ABSTRACT Neuroticism is widely used as an explanatory concept in etiological research of psychopathology. To clarify what neuroticism actually represents, we investigated the phenotypic and genetic relationship between neuroticism and the morning cortisol secretion. In the current classic twin study, 125 female twin pairs (74 monozygotic and 51 dizygotic pairs) participated. For each participant, 4 different neuroticism scores were available to calculate a neuroticism composite score that was used in the statistical analyses. The morning cortisol secretion was assessed by 4 salivary samples in the 1st hour after awakening. Significant genetic influences for the neuroticism composite score (55%), and each of the 4 cortisol samples (52%–69%) were found. There was no phenotypic or genotypic relationship between neuroticism and morning cortisol secretion. Although neuroticism and cortisol were both heritable traits, they did not share any genetic influences.