Title

Season of Birth and Dopamine Receptor Gene Associations with Impulsivity, Sensation Seeking and Reproductive Behaviors

Document Type

Article

Publication Date

11-2007

Keywords

Genetics And Genomics ; Neuroscience ; Developmental Biology -- Neurodevelopment ; Evolutionary Biology -- Sexual Behavior ; Neuroscience -- Behavioral Neuroscience ; Neuroscience -- Neurodevelopment ; Evolutionary Biology -- Human Evolution

Abstract

Season of birth (SOB) has been associated with many physiological and psychological traits including novelty seekingand sensation seeking. Similar traits have been associated with genetic polymorphisms in the dopamine system. SOB and dopaminereceptor genetic polymorphisms may independently and interactively influence similar behaviors through their common effects on the dopaminergic system. ; Based on a sample of 195 subjects, we examined whether SOB was associated with impulsivity, sensationseeking and reproductive behaviors. Additionally we examined potential interactions of dopamine receptor genes with SOB for the same set of traits. Phenotypes were evaluated using the Sociosexual Orientation Inventory, the Barratt Impulsivity Scale, the EysenckImpulsivity Questionnaire, the Sensation Seeking Scale, and the Delay Discounting Task. Subjects were also asked about their age at first sex as well as their desired age at the birth of their first child. The dopamine gene polymorphisms examined were Dopamine Receptor D2 () and D4 () . Primary analyses included factorial gender×SOB ANOVAs or binary logistic regression models for each dependent trait. Secondary analysis extended the factorial models by also including and genotypes as independent variables. Winter-born males were more sensation seeking than non-winter born males. In factorial models including both genotype and season of birth as variables, two previously unobserved effects were discovered: (1) a SOB× interaction effect on venturesomeness and (2) a DRD2× interaction effect on sensation seeking. ; These results are consistent with past findings that SOB is related to sensation seeking. Additionally, these results provide tentative support for the hypothesis that SOB modifies the behavioral expression of dopaminergic genetic polymorphism. These findings suggest that SOB should be included in future studies of risky behaviors and behavioral genetic studies of the dopamine system.

Publisher Attribution

Eisenberg, D., Campbell, B., MacKillop, J., Lum, J., Wilson, D., & Soares, D. (2007). Season of Birth and Dopamine Receptor Gene Associations with Impulsivity, Sensation Seeking and Reproductive Behaviors (Birth Season and Behavior). PLoS ONE, 2(11), E1216.