title: The association of DRD4 and novelty seeking is found in a nonhuman primate model.
abstract: OBJECTIVE
  The association of novelty seeking with a repeat polymorphism in the coding region of the dopamine D4 receptor gene (DRD4) has been demonstrated in several human populations, but not in others. The objective of this study was to test the generality of the association in a captive nonhuman primate population of known history, using objective methods for assessing novelty seeking and a pedigree-based association design.
  
  
  METHODS
  Four hundred and fifty two socially-living vervet monkeys (Cercopithecus aethiops) from a large multigenerational pedigree at the UCLA-VA Vervet Research Colony were studied. Two variants in the 48 base pair repeat in exon III of the DRD4 gene have been found in this population, a six-repeat (92%) and a less common five-repeat (8%). Novelty seeking was measured by the latency to approach a large and potentially threatening novel object placed in the home enclosure. Heritability of novelty seeking and the association of novelty seeking with the DRD4 polymorphism were assessed using variance component modeling as implemented in Sequential Oligogenic Linkage Analysis Routines.
  
  
  RESULTS
  The variance component analysis indicated that the DRD4 variant explained a significant portion of the total variance in novelty seeking. The final model included a significant effect of the DRD4 polymorphism (P=0.03), which explained 13% of the phenotypic variance, and a significant remaining genetic effect (h=0. 467+/-0.095, P<0.0001).
  
  
  CONCLUSIONS
  The association of DRD4 with novelty seeking has now been replicated in a nonhuman primate species, the vervet monkey.
authors.affiliation: Center for Primate Neuroethology, Semel Institute for Neuroscience and Human Behavior, University of California at Los Angeles, Los Angeles, California 90095, USA. jbailey@mednet.ucla.edu
authors.forename: Julia N
authors.initials: JN
authors.lastname: Bailey
authors.forename: Sherry E
authors.initials: SE
authors.lastname: Breidenthal
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Jorgensen
authors.forename: James T
authors.initials: JT
authors.lastname: McCracken
authors.forename: Lynn A
authors.initials: LA
authors.lastname: Fairbanks
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002522:Chlorocebus aethiops; D004247:DNA / Q000097:blood / Q000235:genetics / Q000302:isolation & purification; D005106:Exploratory Behavior / Q000502:physiology*; D014644:Genetic Variation; D023421:Models, Animal; D010641:Phenotype; D011110:Polymorphism, Genetic; D050638:Receptors, Dopamine D4 / Q000235:genetics*; D012919:Social Behavior
chemical_list: D050638:Receptors, Dopamine D4; D004247:DNA