Mind-reading receptors: The role of the vasopressin receptor 1a gene (AVPR1A) in human empathy, social interaction and health

Abstract

Social support is beneficial for human mental and physical health, whereas experiencing social strain can be detrimental. The impact of social interaction varies between individuals and this variation may partly be driven by biological factors. Evidence suggests that variation in the 5' promoter region of the vasopressin 1a receptor gene (AVPR1A) influences individual differences in human social behaviours, social cognition, and how a person responds to their social environment. The research described in this thesis aimed to determine whether variation in the short tandem repeat polymorphism AVPR1A RS3 was directly associated with individual differences in mental and physical health, and whether AVPR1A RS3 genotype moderated the impact of social support and social strain on health. The project also aimed to explore the relationship between AVPR1A RS3 variation and empathy, a trait that could provide a link between AVPR1A and health outcomes.

Relationships between genetic variation and social and health phenotypes were explored. Two series of nested multi-level linear models found a significant association between AVPR1A RS3 genotype and women's self-reported physical and mental health. Results indicate that women carrying one or two copies of the Short RS3 allele report better mental and physical health than women homozygous for the Long RS3 allele. There was some evidence of an interaction between genotype and social support and strain variables, but the overall pattern of interaction effects was unclear. No direct relationship between AVPR1A and health was found for men. Due to the limitations of the data set used, a population-based analysis and a twin-modelling analysis could not draw strong conclusions about the relationship between AVPR1A RS3 genotype and individual differences in empathy. However, within the context of existing literature, the results of this project support the hypothesis that genetic variation at the RS3 locus is associated with individual differences in tendency to empathise and cognitive empathy skill.

In this project, empathy was measured using three short-form versions of two common empathy measures, the Empathy Quotient and the Reading the Eyes in the Mind Test. The psychometric properties of these measures were explored to determine if they were appropriate for use in future research. A short-form of the Empathy Quotient, the EQ-17, was judged to be appropriate for future use. Two short-forms of the Reading the Mind in the Eyes test, the RMET-17 and RMET-14, were found to have similar psychometric properties to the full-length test, however, results indicated that they were inappropriate for future research use.

The results of this project align with previous research linking AVPR1A RS3 variation with social traits and add new evidence indicating that this genetic variant is also associated with individual differences in women's mental and physical health. The relationship between AVPR1A RS3 genotype and both mental and physical health emphasises the importance of continuing to improve our understanding of the vasopressin system in human social behaviour. Show more