Student Prize Award Abstract
2004 Poster Paper Award
INFANT TEMPERAMENT AND RESPONSE TO MATERNAL SEPARATION ARE ASSOCIATED WITH SEROTONIN GENOTYPE IN RHESUS MACAQUES
G. M. Karere1; E. L. Kinnally1,3; L. A. Lyons1,2 and J. P. Capitanio1,3
1California National Primate Research Center, One Shields Avenue, Davis, CA, 95616, USA, 2Population Health and Reproduction, Veterinary Medical School, University of California at Davis, 3Department of Psychology, University of California at Davis
Polymorphism in the monoamine oxidase A (MAOA) promoter region , which influences central nervous system serotonin function, has been associated with individual variation in aggressiveness/impulsiveness in adult humans (Caspi, et al., 2002, Manuck et al., 2000) and primates (Bennett et al., 2002). The present study investigated the relationship between behavioral characteristics and MAOA-linked promoter region (rhMAOA-LPR) genotype in 63 field-cage raised infant rhesus macaques. Subjects experienced a maternal separation and relocation during a 24-hr. period at 3-4 months of age. Assessments included focal behavioral observations as well as ratings on twenty "temperament" adjectives. Subject DNA was genotyped for rhMAOA-LPR via polymerase chain reaction. Data were analyzed using one-way ANOVAs and post hoc t-tests. In response to separation and relocation, subjects homozygous for the medium-length rhMAOA-LPR exhibited less cooing, tooth-grinding, lipsmacking, and appendage sucking (all p < .05) than subjects with any other genotype. Subjects homozygous for the shortest version of MAOA-LPR however, tended to coo, tooth-grind and bark more than other infants (all p < .06). In addition, homozygous/medium animals were rated to be significantly less calm, less flexible, more fearful, and more nervous (all p < .05), and tended to be less bold and less confident than other animals (both p = .06). The present data are consistent with research that shows that MAOA genotype is associated with emotional reactivity during stressful situations.