Skip to main content
  • Poster presentation
  • Open access
  • Published:

Gene-environment interaction and personality/behaviour


Genes and environment interact to form an individual's personality. Abnormal or extreme behaviour could thus be explained by hereditary factors in combination with poor environmental conditions, as shown by Caspi et al., 2002 and replicated e.g. by Foley et al., 2004.

Materials and methods

The MAO-A and 5-HTT genes are two key players in the regulation of serotonin turnover within the brain. Functional variations in the promoter regions allow for division of both these genes into a short and a long allele proven to exert low and high transcriptional activities, respectively (Sabol et al., 1998; Lesch et al., 1996). AP-2ß is a transcription factor of importance for development and maintenance of, among other structures, the monoamine brain-stem nuclei. An AP2ß gene polymorphism has been shown to be associated with personality and monoamine turnover (see Damberg, 2005).


The results were in the same direction for all behavioural phenotypes/disorders, showing that genotype is dependent on psychosocial factors for penetration. The short MAO-A allele interacted with psychosocial factors with regard to risk for criminal activity (60% of the variance) and destructive behaviour when drunk. With regard to 5-HTT genotype, heterozygous subjects reporting Bad family relations showed a 13 fold increased risk for high intoxication frequency. Increased anorectic problems were seen in individuals carrying the short allele, if in interaction with Bad family relations (p = 0.009). AP-2 genotype interacted significantly with psychosocial environment with regard to risk for criminality, alcohol intake as well as depressive symptoms in girls.


In conclusion, genotype and a wide variety of psychosocial factors interact significantly, above what would be expected from simple additive effects, to precipitate a variety of behavioural and psychiatric disorders. Background, methods and some results are to be found in ref 1–4


  1. Nilsson KW, Sjöberg RL, Damberg M, Leppert J, Öhrvik J, Alm P-O, Lindström L, Oreland L: Role of MAO-A genotype and psychosocial factors in male adolescent criminal activity. Biol Psychiat. 2005,

    Google Scholar 

  2. Nilsson KW, Sjöberg RL, Damberg M, Alm PO, Öhrvik J, Leppert J, Lindström L, Oreland L: The role of the 5-HTT gene and family function in adolescent alcohol consumption. Alc Clin Exp Res. 2005, 29: 564-70. 10.1097/01.ALC.0000159112.98941.B0.

    Article  CAS  Google Scholar 

  3. Sjöberg RL, Nilsson KW, Nordquist N, Öhrvik J, Leppert J, Lindström L, Oreland L: Development of depression: sex and the interaction between environment and promoter polymorphism of the serotonin transporter gene. Int J Neuropsychopharmacology. 2005,

    Google Scholar 

  4. af Klinteberg B, von Knorring L, Oreland L: On the psychobiology of impulsivity. On the psychobiology of personality: essays in honour of Marvin Zuckerman. Edited by Stelmack RM. Amsterdam: Elsevier. 2004, 455-478.

    Google Scholar 

Download references

Author information

Authors and Affiliations


Rights and permissions

Open Access This article is published under license to BioMed Central Ltd. This is an Open Access article is distributed under the terms of the Creative Commons Attribution 2.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Reprints and permissions

About this article

Cite this article

Oreland, L., Hallman, J., Lindström, L. et al. Gene-environment interaction and personality/behaviour. Ann Gen Psychiatry 5 (Suppl 1), S77 (2006).

Download citation

  • Published:

  • DOI: