title: What is an "adverse" environment? Interactions of rearing experiences and MAOA genotype in rhesus monkeys.
abstract: BACKGROUND
  Studies have been inconsistent in demonstrating that early adversity and specific genotype can be joint risk factors for poor behavioral outcomes. Using a rhesus monkey model, we examined how social context and different forms of early adversity influence whether a specific genotype (polymorphism in the promoter region of monoamine oxidase A [MAOA]) affects display of aggressive, fearful, and anxious behaviors.
  
  
  METHODS
  Rhesus monkey infants (n = 473) were exposed to brief social challenge at age 3-4 months. Infants were reared 1) with mothers and up to 150 other animals in large cages; 2) with mothers in smaller social groups; 3) with mother and access to, at most, one other mother-infant pair; and 4) without mother but with access to a same-age peer in a nursery.
  
  
  RESULTS
  No effects of genotype were found for infants reared by mothers in large social cages, although several genotype by rearing environment interactions were evident. Animals reared in smaller social groups were more likely to display aggression, which was especially true of animals possessing the low-activity MAOA genotype. In addition, animals with low-activity genotypes that had experienced restricted mother rearing showed more anxious behavior (scratch, yawn).
  
  
  CONCLUSIONS
  Among mother-reared animals, broader contextual features, associated with the social environment and experience of the mother, can affect the extent to which genotype contributes to behavioral expression under conditions of challenge. Results also suggest that different forms of early adverse experience can affect the types of responses displayed by animals of different genotypes.
authors.affiliation: Department of Population Health and Reproduction, University of California, Davis, CA, USA.
authors.forename: Genesio M
authors.initials: GM
authors.lastname: Karere
authors.forename: Erin L
authors.initials: EL
authors.lastname: Kinnally
authors.forename: Jessica N
authors.initials: JN
authors.lastname: Sanchez
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Famula
authors.forename: Leslie A
authors.initials: LA
authors.lastname: Lyons
authors.forename: John P
authors.initials: JP
authors.lastname: Capitanio
mesh_terms: D000374:Aggression; D000818:Animals; D000831:Animals, Newborn; D001007:Anxiety / Q000235:genetics*; D005260:Female; D005838:Genotype; D008253:Macaca mulatta; D008297:Male; D008425:Maternal Behavior; D008426:Maternal Deprivation; D008995:Monoamine Oxidase / Q000235:genetics* / Q000378:metabolism; D012931:Social Environment
chemical_list: D008995:Monoamine Oxidase