The Genetic Basis Of (Group-Directed) Altruism

Abstract

Very young children voluntarily share with others. Such early emergence of altruistic behaviours in early development suggests possible biological mechanisms. The neuropeptide oxytocin is well known for playing a role in social affiliation and has been shown to influence prosocial behaviours in adults. Sparse research has been conducted on how the gene for the oxytocin receptor influences prosocial behaviour and altruism in young children. Interestingly, oxytocin’s effects on prosocial behaviour has been shown to be bounded within social groups, enhancing ingroup bias. Much of the research has been conducted on adults, again with sparse research conducted on oxytocin’s effects on ingroup bias earlier in development. Thus, there is an obvious space to conduct novel research into how the oxytocin receptor gene influences ingroup biases in young children. The present research investigates how the OXTR gene influences children’s altruistic sharing at 3-years of age, and children’s ingroup biases at 4-years of age by analysing data from 152 children involved in the Origins of Cooperative Actions longitudinal study. Children’s OXTR gene (rs53576) was sequenced when they were infants and altruistic sharing was measured when they were 3- and 4-years of age using the Dictator Game (DG). During the 4-year old session, children were placed into minimal groups (yellow versus green) before playing the DG. Analyses revealed that the OXTR gene did not influence how many stickers children shared at 3-years of age, nor did it have any significant interactive effect with minimal groups on altruistic sharing at 4-years of age. However, children with the GG genotype were significantly more likely to give their first stickers to others, instead of themselves. Boys were also shown to be significantly more likely to give their first stickers to others than girls. Lastly, girls shared significantly more stickers with ingroup members than boys. These finding provide evidence suggesting that OXTR gene may not enhance overall generosity of altruistic sharing, but may motivate children to consider others first in their actions.