Associations between spouses’ oxytocin receptor gene polymorphism, attachment security, and marital satisfaction

RESEARCH ARTICLE Associations between spouses’ oxytocin receptor gene polymorphism, attachment security, and marital satisfaction Joan K. Monin ID1*, Selin O. Goktas2, Trace Kershaw1, Andrew DeWan3 1 Social and Behavioral Sciences, Yale School of Public Health, New Haven, CT, United States of America, 2 Psychiatry, Yale School of Medicine, New Haven, CT, United States of America, 3 Chronic Disease Epidemiology, Yale School of Public Health, New Haven, CT, United States of America a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 OPEN ACCESS Citation: Monin JK, Goktas SO, Kershaw T, DeWan A (2019) Associations between spouses’ oxytocin receptor gene polymorphism, attachment security, and marital satisfaction. PLoS ONE 14(2): e0213083. https://doi.org/10.1371/journal. pone.0213083 Editor: Alexandra Kavushansky, Technion Israel Institute of Technology, ISRAEL Received: November 28, 2018 * Abstract OXTR rs53576, a polymorphism on the oxytocin receptor gene, has previously been linked to individual differences in social behaviors. That is, individuals with the GG genotype show greater empathy, sociability, and emotional stability. In the context of close relationships, such psychological resources are associated with better relationship outcomes. However, no studies to our knowledge have examined associations between spouses’ OXTR polymorphisms, attachment security, and marital satisfaction. In the current study, 178 married couples (N = 356; ages 37–90) completed self-report measures of attachment security and marital satisfaction and provided saliva samples for genotyping. Results from Actor Partner Interdependence Models showed that individuals who had the GG genotype (actor effect) or had a spouse with the GG genotype (partner effect) reported greater marital satisfaction than individuals with AA or AG genotypes. Furthermore, greater attachment security mediated associations between GG genotype and marital satisfaction. Accepted: February 14, 2019 Published: February 28, 2019 Copyright: © 2019 Monin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: The data is in the Supporting Information files. Funding: Funding sources include a career development award to Joan Monin from the National Institute on Aging, National Institutes of Health, K01 AG042450-01A1 and an award from Yale’s Claude D. Pepper Older Americans Independence Center, P30AG021342 (https:// www.nia.nih.gov/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Introduction Attachment security, the feeling of emotional safety that comes from a history of close others being responsive to one’s needs, is associated with numerous benefits for married couples [1]. Attachment security plays an essential role in effective communication, problem solving, and social support [2,3] and it is a strong predictor of marital satisfaction over time [2]. While attachment security is thought to be influenced mainly by social experiences throughout the life course, a few studies have shown associations with genetic markers [4]. One such genetic marker is the oxytocin receptor (OXTR rs53576) polymorphism which has been linked with psychological resources more broadly, such as social bonding, empathy, sociability, and emotional stability [5]. Although past research has examined associations between genetic markers and attachment security [5,6], no study to our knowledge has examined whether the OXTR rs53576 genotype is associated with relationship outcomes and whether attachment security plays a role in this process. Furthermore, no study has examined these associations using dyadic data. The aim of this study was to examine among midlife and older adult married couples whether one’s own OXTR rs53576 genotype and one’s spouse’s OXTR rs53576 genotype PLOS ONE | https://doi.org/10.1371/journal.pone.0213083 February 28, 2019 1 / 16 Spouses’ OXTR, attachment, and satisfaction Competing interests: The authors have declared that no competing interests exist. are associated with marital satisfaction and whether these associations are mediated by attachment security. Oxytocin receptor gene and social and emotional skills Oxytocin, a hormone produced in hypothalamus within the limbic system, has a central role in the modulation of social and emotional behaviors [7]. High oxytocin plasma concentrations have been implicated in the formation of social relationships such as maternal bonding, attachment, trust, and social affiliation [8]. Recent research on oxytocin has further revealed individual differences in psychosocial tendencies on a genetic level. The mechanism driving these differences is a single nucleotide genetic polymorphism in the oxytocin receptor gene named OXTR rs53576. Carrying a certain type of allele encoded as G and A has been shown to be the genetic marker of differences in social-emotional behavioral traits [9,10]. Being homozygous for the G allele is linked to having better social and emotional skills. For example, a meta-analysis examining the rs53576 polymorphism and sociality found that the G homozygotes responded to others around them more sociably as indicated by greater extraversion and empathy and lower social loneliness than people with AA or AG genotypes [11]. A recent study also showed that people with the GG genotype exhibit higher emotional stability which was associated with greater perceived social support and in turn general self-reported health (10). Notably, empathy and greater awareness of social cues have been consistently related to having a GG genotype [12–14]. Two of the core components of close relationships–trust and fairness have also been associated with OXTR. For example, one study showed that men with the GG genotype displayed more trusting behaviors than men with the A allele in an experiment in which two men participated in an investment game and lottery game measuring trust and risk behaviors, respectively [15]. Similarly, GG men were more trusting of others than AA men in a separate trust game experiment [16]. In another study, naïve observers were presented with silenced video clips of targets who were listening to their romantic partner disclosing a moment of suffering. The observers rated both male and female G homozygote targets as more prosocial in terms of compassion, trustworthiness, and kindness than AG or AA targets in the videos [17]. It has also been shown that individuals with at least one copy of the G (GG/AG) allele benefit more from receiving emotional support than those with the AA genotype. In an experiment in which participants were randomly assigned to receiving either no social support or to receiving social support before a stressful event, carriers (...truncated)