Start date should be earlier than end date. OK Please enter valid date format.

Original Research ARTICLE

This article is part of a Research Topic

Living in a dangerous world: the shaping of behavioral profile by early environment and 5-HTT genotype

Rebecca S. Heiming^1,2, Friederike Jansen^1,2, Lars Lewejohann^1,2, Sylvia Kaiser^1,2, Angelika Schmitt³, Klaus Peter Lesch³ and Norbert Sachser^1,2*

Department of Behavioural Biology, University of Muenster, Muenster, Germany

Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany

Molecular and Clinical Psychobiology, Department of Psychiatry, Psychosomatics and Psychotherapy, University of Wuerzburg, Wuerzburg, Germany

Anxiety and anxiety disorders are influenced by both, environmental and genetic factors. One genetic factor under scrutiny for anxiety disorders is the genetically encoded variation of the serotonin transporter (5-HTT). The aim of this study was to elucidate the effects of a threatening environment during early phases of life on anxiety-like (ANX) and exploratory behavior (EXP) in adult mice, varying in serotonin transporter (5-HTT) genotype. For this purpose, pregnant and lactating 5-HTT +/− dams were repeatedly exposed to olfactory cues of unfamiliar adult males by introducing small amounts of soiled bedding to their home cage. These stimuli signal the danger of infanticide and simulate a threatening environment. Control females were treated with neutral bedding. The offspring (5-HTT +/+, +/−, −/−) were examined for their ANX and EXP. The main results were: (1) a main effect of genotype existed, with 5-HTT −/− showing higher levels of ANX and lower levels of EXP than 5-HTT +/− and wildtypes. (2) When mothers had lived in a threatening environment, their offspring showed increased ANX and reduced EXP compared to controls. (3) These effects were most pronounced in 5-HTT −/− mice. By applying a new ecologically relevant paradigm we conclude: If 5-HTT +/− mothers live in a threatening environment during pregnancy and lactation, their offspring behavioral profile will, in principle, be shaped in an adaptive way preparing the young for an adverse environment. This process is, however, modulated by 5-HTT genotype, bearing the risk that individuals with impaired serotonergic neurotransmission (5-HTT −/−) will develop an exaggerated, potentially pathological level of anxiety from gene × environment interactions.

Keywords:

adaptation, anxiety, behavioral profile, exploration, gene × environment interaction, maternal effects, mice, serotonin transporter

Citation:

Heiming RS, Jansen F, Lewejohann L, Kaiser S, Schmitt A, Lesch KP and Sachser N (2009). Living in a dangerous world: the shaping of behavioral profile by early environment and 5-HTT genotype. Front. Behav. Neurosci. 3:26. doi: 10.3389/neuro.08.026.2009

Received:

30 June 2009;

Paper pending published:

14 July 2009;

Accepted:

19 August 2009;

Published online:

09 September 2009.

Edited by:

Larry J. Young, Emory University School of Medicine, USA; Yerkes National Primate Research Center, USA

Reviewed by:

Alexa H. Veenema, University of Massachusetts, USA
Chadi Touma, Max Planck Institute of Psychiatry, Germany

© 2009 Heiming, Jansen, Lewejohann, Kaiser, Schmitt, Lesch and Sachser. This is an open-access article subject to an exclusive license agreement between the authors and the Frontiers Research Foundation, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are credited.

*Correspondence:

Norbert Sachser, Department of Behavioral Biology, University of Muenster, Badestraße 13, D-48149 Muenster, Germany. e-mail: sachser@uni-muenster.de