title: The oxytocin receptor (OXTR) contributes to prosocial fund allocations in the dictator game and the social value orientations task.
abstract: BACKGROUND
  Economic games observe social decision making in the laboratory that involves real money payoffs. Previously we have shown that allocation of funds in the Dictator Game (DG), a paradigm that illustrates costly altruistic behavior, is partially determined by promoter-region repeat region variants in the arginine vasopressin 1a receptor gene (AVPR1a). In the current investigation, the gene encoding the related oxytocin receptor (OXTR) was tested for association with the DG and a related paradigm, the Social Values Orientation (SVO) task.
  
  
  RESULTS
  Association (101 male and 102 female students) using a robust-family based test between 15 single tagging SNPs (htSNPs) across the OXTR was demonstrated with both the DG and SVO. Three htSNPs across the gene region showed significant association with both of the two games. The most significant association was observed with rs1042778 (p = 0.001). Haplotype analysis also showed significant associations for both DG and SVO. Following permutation test adjustment, significance was observed for 2-5 locus haplotypes (p<0.05). A second sample of 98 female subjects was subsequently and independently recruited to play the dictator game and was genotyped for the three significant SNPs found in the first sample. The rs1042778 SNP was shown to be significant for the second sample as well (p = 0.004, Fisher's exact test).
  
  
  CONCLUSIONS
  The demonstration that genetic polymorphisms for the OXTR are associated with human prosocial decision making converges with a large body of animal research showing that oxytocin is an important social hormone across vertebrates including Homo sapiens. Individual differences in prosocial behavior have been shown by twin studies to have a substantial genetic basis and the current investigation demonstrates that common variants in the oxytocin receptor gene, an important element of mammalian social circuitry, underlie such individual differences.
authors.affiliation: Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors.forename: Salomon
authors.initials: S
authors.lastname: Israel
authors.forename: Elad
authors.initials: E
authors.lastname: Lerer
authors.forename: Idan
authors.initials: I
authors.lastname: Shalev
authors.forename: Florina
authors.initials: F
authors.lastname: Uzefovsky
authors.forename: Mathias
authors.initials: M
authors.lastname: Riebold
authors.forename: Efrat
authors.initials: E
authors.lastname: Laiba
authors.forename: Rachel
authors.initials: R
authors.lastname: Bachner-Melman
authors.forename: Anat
authors.initials: A
authors.lastname: Maril
authors.forename: Gary
authors.initials: G
authors.lastname: Bornstein
authors.forename: Ariel
authors.initials: A
authors.lastname: Knafo
authors.forename: Richard P
authors.initials: RP
authors.lastname: Ebstein
mesh_terms: D000328:Adult; D003361:Cost Allocation; D005260:Female; D005717:Games, Experimental; D006239:Haplotypes; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D018045:Receptors, Oxytocin / Q000235:genetics*; D012919:Social Behavior; D012945:Social Values; D012984:Software; D013647:Task Performance and Analysis
chemical_list: D018045:Receptors, Oxytocin