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The similiarity of facial expressions in response to emotion-inducing films in reared-apart twins

  • K. S. Kendler (a1) (a2), L. J. Halberstadt (a1), F. Butera (a1), J. Myers (a1), T. Bouchard (a3) and P. Ekman (a4)...

While the role of genetic factors in self-report measures of emotion has been frequently studied, we know little about the degree to which genetic factors influence emotional facial expressions.


Twenty-eight pairs of monozygotic (MZ) and dizygotic (DZ) twins from the Minnesota Study of Twins Reared Apart were shown three emotion-inducing films and their facial responses recorded. These recordings were blindly scored by trained raters. Ranked correlations between twins were calculated controlling for age and sex.


Twin pairs were significantly correlated for facial expressions of general positive emotions, happiness, surprise and anger, but not for general negative emotions, sadness, or disgust or average emotional intensity. MZ pairs (n=18) were more correlated than DZ pairs (n=10) for most but not all emotional expressions.


Since these twin pairs had minimal contact with each other prior to testing, these results support significant genetic effects on the facial display of at least some human emotions in response to standardized stimuli. The small sample size resulted in estimated twin correlations with very wide confidence intervals.

Corresponding author
*Address for correspondence: K. S. Kendler, M.D., Department of Psychiatry, Medical College of Virginia, Virginia Commonwealth University, Richmond, VA. USA. (Email:
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Afrakhteh S (2001). Biological bases of expression of emotion [Dissertation Abstract]. Dissertation Abstracts International, p. 6177.
Bouchard TJ Jr., Lykken DT, McGue M, Segal NL, Tellegen A (1990). Sources of human psychological differences: the Minnesota Study of Twins Reared Apart. Science 250, 223228.
Carlson SR, Katsanis J, Iacono WG, McGue M (1997). Emotional modulation of the startle reflex in twins: preliminary findings. Biological Psychology 46, 235246.
Darwin C (1872). The Expression of the Emotions in Man and Animals (1872/1998, 3rd edn). Oxford University Press: Oxford.
Ekman P (1973). Darwin and Facial Expression: A Century of Research in Review. Academic Press: New York.
Ekman P (1993). Facial expression and emotion. American Psychologist 48, 384392.
Ekman P (1999). Facial expressions. In The Handbook of Cognition and Emotion (ed. Dalgleish T. and Power M.), pp. 301320. John Wiley & Sons: Hoboken.
Ekman P (2007). Emotions Revealed, 2nd edn, 2003/2007. H. Holt: New York.
Ekman P, Friesen WV (1975). Unmasking the Face: A Guide to Recognizing Emotions from Facial Clues. Prentice-Hall: Englewood Cliffs, NJ.
Ekman P, Friesen WV (1978). The Facial Action Coding System (FACS): A Technique for this Measurement of Facial Movement. Consulting Psychologists Press: Palo Alto, CA.
Ekman P, Friesen WV, Hager J (2002). The Facial Action Coding System CD ROM. Research Nexus: Salt Lake City, UT.
Ekman P, Irwin W, Rosenberg ER, Hager JC (1997). FACS Affect Interpretation Database (Computer Database). University of California, San Francisco: San Francisco, CA.
Ekman P, Roper G, Hager JC (1980). Deliberate facial movement. Child Development 51, 886891.
Goldsmith HH, Lemery KS (2000). Linking temperamental fearfulness and anxiety symptoms: a behavior-genetic perspective. Biological Psychiatry 48, 11991209.
Hettema JM, Neale MC, Kendler KS (2001). A review and meta-analysis of the genetic epidemiology of anxiety disorders. American Journal of Psychiatry 158, 15681578.
Kendler KS, Heath A, Martin NG, Eaves LJ (1986). Symptoms of anxiety and depression in a volunteer twin population. The etiologic role of genetic and environmental factors. Archives of General Psychiatry 43, 213221.
Kendler KS, Walters EE, Truett KR, Heath AC, Neale MC, Martin NG, Eaves LJ (1994). Sources of individual differences in depressive symptoms: analysis of two samples of twins and their families. American Journal of Psychiatry 151, 16051614.
Loehlin JC (1992). Genes and Environment in Personality Development. Sage Publications: Newbury Park, CA.
McGuffin P, Rijsdijk F, Andrew M, Sham P, Katz R, Cardno A (2003). The heritability of bipolar affective disorder and the genetic relationship to unipolar depression. Archives of General Psychiatry 60, 497502.
Papadatos C, Alexiou D, Nicolopoulos D, Mikropoulos H, Hadzigeorgiou E (1974). Congenital hypoplasia of depressor anguli oris muscle: A genetically determined condition? Archives of Disease in Childhood 49, 927931.
Peleg G, Katzir G, Peleg O, Kamara M, Brodsky L, Hel-Or H, Keren D, Nevo E (2006). Hereditary family signature of facial expression. Proceedings of the National Academy of Sciences USA 103, 1592115926.
Rebollo I, Boomsma DI (2006). Genetic analysis of anger: genetic dominance or competitive sibling interaction. Behavior Genetics 36, 216228.
Roysamb E, Tambs K, Reichborn-Kjennerud T, Neale MC, Harris JR (2003). Happiness and health: environmental and genetic contributions to the relationship between subjective well-being, perceived health, and somatic illness. Journal of Personality & Social Psychology 85, 11361146.
Sullivan PF, Kendler KS, Neale MC (2003). Schizophrenia as a complex trait: evidence from a meta-analysis of twin studies. Archives of General Psychiatry 60, 11871192.
Sullivan PF, Neale MC, Kendler KS (2000). Genetic epidemiology of major depression: review and meta-analysis. American Journal of Psychiatry 157, 15521562.
Tellegen A, Lykken DT, Bouchard TJ Jr., Wilcox KJ, Segal NL, Rich S (1988). Personality similarity in twins reared apart and together. Journal of Personality & Social Psychology 54, 10311039.
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Psychological Medicine
  • ISSN: 0033-2917
  • EISSN: 1469-8978
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