Abstract # 126:

Scheduled for Friday, August 18, 2006 03:00 PM-03:20 PM: Session 13 (Regency East #1) Oral Presentation

Effects of Maternal Genotype and Offspring Genotype on the Quality of the Mother-Infant Relationship in Vervet Monkeys (Chlorocebus aethiops)

L. A. Fairbanks, S. Breidenthal, J. N. Bailey and M. J. Jorgensen
Semel Institute, UCLA, 740 Westwood Plaza, Los Angeles, CA 90024, USA
     In contrast to the widely held belief that differences in early experience influence development, behavioral genetics studies typically find little effect of the common family environment on personality. Recent research has looked for evidence of non-shared family influences and gene-environment interactions to resolve this dilemma. A polymorphism in the dopamine D4 receptor gene (exon 3, 48 BP VNTR) associated with novelty seeking and attention-deficit/hyperactivity disorder in humans has also been related to novelty seeking in vervets. Juvenile and adult vervets with the 5-repeat variant are quicker to approach a novel stimulus than individuals with the more common 6-repeat variant. Here we present results of the association of this DRD4 repeat polymorphism with maternal and infant behavior, and preliminary indications of interactions between maternal genotype and infant genotype in the quality of the mother-infant interaction. In a sample of 207 mother-infant dyads, 15 mothers and 14 infants had the 5-repeat genotype. Infants with the 5-repeat genotype were more active (t=2.23, p=0.03) and played a larger part in breaking contact with the mother (t=2.04, p=0.04) than infants with the 6-repeat. Mothers with the 5-repeat genotype were less rejecting (t=2.55, p=0.02) than mothers with the common 6-repeat genotype. The most conflict in the mother-infant relationship was evident for common type mothers with 5-repeat infants. These results provide a framework for understanding non-shared family influences in early development.