Genomics: Insight

How can genomics help answer the free will vs. determinism question regarding altruism?

Nathaniel Marko
April 10, 2022

Altruism, the trait of sacrificing self-gain for the benefit of others, may be expressed as a result of both genes and environmental influence. 

The idea that selflessness could be predetermined is utterly fascinating. When someone gives money to a homeless person, are they acting out of their own conscious morality, or has the susceptibility for this action already been embedded within them since birth? With an increasing wealth of knowledge concerning the role of genetics on human life, what might be the role of genes in the expression of altruistic behavior? Here, we review three experiments that examine the role of conscious selflessness and can further our understanding of this fascinating trait.

With an increasing wealth of knowledge concerning the role of genomics on human life, what might be the role of genes in the expression of altruistic behavior?

Tests on human populations can be performed by genotyping single nucleotide polymorphisms (SNPs) that are thought to be connected to altruism. An SNP within the oxytocin receptor gene was genotyped in a 2009 experiment performed in Israel. The test subjects were put through the “dictator game”, an experiment that places the participant in a situation in which altruism is costly to the individual. The subject was given a certain amount of money and told to divide it up between themselves and one other person however they please. The recipient played a passive role in the experiment, holding no part in the decision-making process and only choosing whether to accept or reject the offer, the latter of which would cause both players to lose all their money. However, because it was in the receiver’s best interests to take any value of money above $0, they were essentially taken out of the equation, and the game becomes solely about the participant’s level of selflessness. By correlating the money given by the test subjects with the presence or absence of the tested SNP alleles, a conclusion would be drawn regarding the extent to which the oxytocin gene influences altruism. The data collected by the study found a high correlation between prosocial behavior and possession of the G Allele within the rs1042778 SNP of the oxytocin receptor. Subjects with the G Allele were found to be “high givers” (above the benchmark of 25 of the experiment’s made-up currency) 64.7% of the time, while those with the T Allele passed the benchmark only 26.5% of the time. The data obtained by this study supports the claim this gene may play a role in altruistic behavior.1

A similar experiment was performed in 2010 using almost identical methods but obtaining vastly different results. Testing the rigor of the 2009 experiment which came out in favor of genetic control, the experimenters used the dictator game, as the means by which to analyze the correlation between SNPs of the oxytocin receptor and prosocial behavior. In this instance, the dictator game was unable to produce a conclusive correlation between genetics and altruism. High giving, although slightly more prevalent within the G Allele group, was not differentiable enough between the two pools to provide support for a decisive connection. Even after running the data through highly rigorous modes of analysis, accounting for sex differences as well as additive and non-additive hereditary models, the data failed to pass the statistical tests needed for a conclusive result to be obtained. Although offering the possibility that geographical location (this experiment was performed in Sweden, the previous in Israel) and test pool size could account for such a lack of genetics-altruism correlation and the authors ultimately rejected the findings of the preceding study. However, they did not definitively conclude that no such correlation could exist.2

In a 1974 study of altruism, individuals were asked to perform a certain concentration task (such as handwriting) while subjected to varying levels of stimulus overload (loud and distracting noises). Some were bombarded with sound, others were subjected to similar levels of overload but with limited degrees of control over it, and for the final group sound was removed as a factor entirely. After the task was completed, they were then approached by a seemingly unassociated person asking for a favor. The correlation between their choice whether to assist and their level of sensory overload was used to demonstrate a possible environmental influence on altruism. The data revealed that the less sound they were targeted with, the more time and effort they spent assisting the “unassociated” individual who appeared after the experiment.3 Though not directly related to the scientific debate on the correlation between SNPs within the oxytocin receptor and selflessness, this study adds another layer of complexity by suggesting that environmental factors may play a role in altruistic behavior.

The only conclusion that can be drawn from these three collectively examined studies is the immense complexity of the behavior of selflessness in terms of the role of genes and environment.

The convergence of the three studies discussed above raises more questions than it does answers. Though one study found a decisive correlation between the rs1042778 SNP and altruism, another demonstrated little to no connection whatsoever. Adding to this uncertainty is the potential influence of environmental factors, which may affect the prevalence and degree of altruistic behavior. Thus, it cannot be said that genetics or the environment alone influence altruism. The only conclusion that can be drawn from these three collectively examined studies is the immense complexity of the behavior of selflessness in terms of the role of genes and environment.


  1. Israel S;Lerer E;Shalev I;Uzefovsky F;Riebold M;Laiba E;Bachner-Melman R;Maril A;Bornstein G;Knafo A;Ebstein RP; (2009, May 20). The oxytocin receptor (OXTR) contributes to prosocial fund allocations in the dictator game and the social value orientations task. PloS one. Retrieved from 
  2. Apicella CL;Cesarini D;Johannesson M;Dawes CT;Lichtenstein P;Wallace B;Beauchamp J;Westberg L; (2010, June 13). No association between oxytocin receptor (OXTR) gene polymorphisms and experimentally elicited social preferences. PloS one. Retrieved from 
  3. Sherrod, D. R., & Downs, R. (1974, September). Environmental determinants of altruism: The effects of stimulus overload and perceived control on helping. Journal of Experimental Social Psychology. Retrieved from 
  4. Okasha, S. (2013, July 21). Biological altruism. Stanford Encyclopedia of Philosophy. Retrieved from 
  5. O’Connor, T., & Franklin, C. (2018, August 21). Free will. Stanford Encyclopedia of Philosophy. Retrieved from

About the Author

Nathaniel Marko

Junior attending Polytechnic High School in Pasadena, California. Fascinated with philosophy and its reaction to scientific developments.