Tuesday, 5 June 2012


Thin-slicing study of the oxytocins receptor (OXTR) gene and the evaluation and expression of the prosocial disposition.
by Lauren Baxter
Based on the study; Kogan, Aleksandr (2011). "Thin-slicing study of the oxytocin receptor (OXTR) gene and the evaluation and expression of the prosocial disposition".PNAS : Proceedings of the National Academy of Sciences (0027-8424), 108 (48), p. 19189.

Otis Redding and Glen Campbell sang about it in the 60’s with “Try a Little Kindness/Tenderness”  and Frederick Buechner once wrote “compassion is sometimes the fatal capacity for feeling what it is like to live inside someone else’s skin”(1926) but could how kind you are be affected by a single gene. Surely one would believe personality traits are determined by a multitude of both genetic and epigenetic factors but could this single-gene paradigm be ultimately a defining factor in the evaluation and expression of the prosocial disposition.

 Scientists at the University of Toronto Mississauga, Canada have completed a study in which the behavioural manifestations were observed of the oxytocin receptor (OXTR) gene. A single-nucleotide polymorphism is defined as single base-pair site in a genome where nucleotide variation can be found. (Campbell, N. 2008)

In this instance, SNP rs53576 has been implicated in pro-social behaviour. Homozygous subjects carrying the G allele of the rs53576 SNP of the gene exhibit more prosocial behaviour than the respective A allele carriers. (Kogan, A. 2011) Largely involved in both social and emotional procedures, Oxytocin is a neuropeptide produced within the hypothalamus. (Sofronew, M. 1983; Bartz, JA. 2006) Within humans, experiments have been conducted that show an increase in oxytocin leads to an increase respectively with facets of prosociality including trust, generosity and empathy. (Kosfeld, M. 2005; Zak, PJ. 2007; Bazara, J. 2009) In comparison to individuals homozygous for the A allele, carriers of the G allele are at a decreased risk to develop autism and through methods of self-analysis, report higher levels of this prosocial disposition. (Tost, H. 2010)In a neurological sense, carriers of the G allele often have a larger hypothalamus and amygdala activity. (Tost, H. 2010)

In the present study, scientists subjected a sample of 116 observers to watch 20 second, silenced video clips of 23 target individuals with varying genotypes listening to a romantic partner reveal a personal experience of suffering. It was hypothesised that individual differences in the genotype would predict how prosocial observers judge target individuals; that carriers of the G allele would indicate pro-sociability through non-verbal displays and that variations in targets’ nonverbal displays of affiliative cues would account for said judgement differences. (Kogan, A. 2011)

Although undoubtedly, social traits are influenced by a multitude of factors, the variation in rs53576 is a certainly a contributing factor. The study concluded people with the ‘GG’ version of the OXTR gene were judged to be kinder than those with ‘GA’ or ‘AA’ versions due to those carrying said ‘GG’ variation displaying more non-verbal empathetic gestures. (Kogan, A. 2011) Overall, the results support the hypotheses and therefore the communicability of slight genetic variations and the influence of the human mind to recognize nonverbal displays connected with specific genotypes. However further research will need to be conducted in order to understand the pathways through which genes prejudice behaviour. Furthermore, what are the implications of this within humanity? Is gene therapy the answer to a more empathetic society? Or could the knowledge of gene expression become an impost on human relationships?


References and Further Reading
Barraza, Jorge A. (01.06.2009). "Empathy toward Strangers Triggers Oxytocin Release and Subsequent Generosity". Annals of the New York Academy of Sciences (0077-8923), 1167 (1), p. 182.
Bartz, JA. Hollander, E. (2006) The neuroscience affiliation; Forging links between basic and clinical research on neuropeptides and social behaviour. Horm Behav. 50:518-528.
Campbell, N. et al. (2008) Biology. 8th ed. Boston; Pearson Education Inc.
Inoue, T. et al. (1994) Structural organization of the human oxytocin receptor gene. J Biol Chem. 269:32451-32456.
Kogan, Aleksandr (2011). "Thin-slicing study of the oxytocin receptor (OXTR) gene and the evaluation and expression of the prosocial disposition".PNAS : Proceedings of the National Academy of Sciences (0027-8424), 108 (48), p. 19189.
Kosfeld, M., Heinrichs, M., Zak, P.J., Fischbacher, U. & Fehr, E. 2005, "Oxytocin increases trust in humans", Nature, vol. 435, no. 7042, pp. 673-6.
Soforoniew, M. (1983) Vasopressin and oxytocin in the mammalian brain and spinal cords. Trends Neurosci. 6:467-472.
Zak, PJ. Stanton, AA. Ahmadi, S. (2007) Oxytocin increases generosity in humans. PLoS ONE. 2:e1128.

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