• By Laura Whybra
  • Posted on Thursday 23rd May, 2013

Environment trumps genes for baby-parent bonds in maltreated children #2 #2

strong>Genetic variation does affect the way ordinary children bond with their parents – but one study finds that maltreatment by parents overpowers the contribution of genes. The good news is that interventions improve bonding for maltreated babies of all genetic types.How can the best interventions be made better? Leading specialists in developmental psychopathology argue that “even well-supported, cost-effective interventions can be improved upon.” Their argument is that standard prevention programs do not work for everybody.Normally, the variation in outcomes is taken for granted. But what if the difference is rooted in children’s genes? Some children might have a genetic predisposition that increases, or reduces, their sensitivity to particular environmental inputs. If this were true, unlocking the genetic key could result in better interventions.In a novel study, a team of researchers from the Mt. Hope Family Center, University of Rochester, investigated this possibility by looking at whether particular genes influence the development of attachment problems amongst maltreated children. They also looked at whether children’s genetic make-up influenced the impact of early intervention for this group of vulnerable children.Their findings demonstrate the power of environmental conditions – both positive and negative – to trump genetic variation.They discovered that genetic variation did affect the way children bonded with their parents – but only among children who were not maltreated. Maltreatment by parents overpowered the contribution of genes. However, positive inputs were also more powerful than genes: among children who were maltreated, interventions were effective regardless of the children’s genetic variations.Genes, maltreatment and attachmentForming a bond to a parent or primary caregiver is an important developmental milestone for every child. The nature of that bond, or attachment, heavily influences the way that infants regulate their negative emotions and learn to deal with stressful circumstances. There are different types of attachment and some are more adaptive than others.“Disorganized attachments” are particularly problematic. An infant with a disorganized attachment displays unusual, sometimes bizarre behaviors when interacting with their mother and often experiences serious psychological and social difficulties throughout childhood and into later life.Frightened or frightening parental behavior is one of the main causes. Maltreated children are at much higher risk of developing disorganized attachments with their mothers than non-maltreated children. An expert on attachment, Marinus van IJzendoorn, explains that “the parent is at the same time the source of fright as well as the only potential haven of safety. In the face of this paradoxical situation, the infants’ organized strategy to deal with stress is expected to fall apart. The essence of disorganized attachment is fright without solution.”However, not all children exposed to maltreatment develop disorganized attachment. If genes have a role in determining which children develop this problem and which don’t, there are important consequences for the likely success of any intervention.Investigating the linkThe Mt. Hope Family Center study involved approximately 150 one-year old infants and compared children exposed to early maltreatment to those exposed to less adverse family contexts.Two-thirds of the sample comprised a maltreatment group - infants living at home with their biological mothers and who have been maltreated (66%) or whose siblings have been maltreated (34%). Typically these children (or their siblings) had been exposed to a form of physical or emotional abuse and/or neglect.The remaining third of the sample was made up of infants living in less adverse circumstances who acted as a comparison group. The incidence of poverty was very high in the sample of maltreating families, so mothers and infants in low-income families (where there is no evidence of maltreatment) were recruited for comparison.The investigation revealed that in seriously adverse conditions, such as those faced by maltreated children, genes have very little influence over attachment outcomes. Maltreated children are highly likely to develop attachment problems, regardless of the type of gene variant they possess. (The genes most significant to questions of attachment are 5-HTT and DRD4.)The same was not true of children from, relatively speaking, more nurturing environments. For these children, genetic variation did influence the development of attachment problems. Children with the genetic variants were more likely to develop disorganized attachments.Investigators Dante Cicchetti, Fred Rogosch, and Sheree Toth conclude that “the differential influence of genes for these two demographically comparable groups of young children highlights the deleterious effects of early disturbances in caregiving on the development of attachment disorganization, with genetic variation minimally involved when environmental stress and failures in care-giving are extreme.”The conclusion drawn from these findings is that while genetics clearly contributes to the development of attachment difficulties, maltreatment by parents overpowers the contribution of genes.What does this mean for prevention and early intervention?Part of the study involved testing the effectiveness of two potential interventions. Families in the maltreatment group were randomly divided into three groups. The first received child-parent psychotherapy, the second a psycho-educational parenting intervention, and the third services as usual.The two interventions are designed to increase attachment security and decrease disorganized attachment, through improvements in the quality of mother-infant relationships and better parenting.Cicchetti and colleagues found that both psychotherapy and the psycho-educational parenting program significantly improved children’s attachment organization. What is more, “genetic variants did not alter the receptiveness of the children to benefit from the interventions. Rather, the interventions proved efficacious, irrespective of genetic variation in the children.”This research sends a clear message. The effects of maltreatment on children’s ability to form attachments are profound – maltreatment is more powerful than our own DNA. And positive environmental inputs, such as the interventions tested in this study, are also very powerful. Their positive effects are not hampered by children’s genetic make-up, leaving very little doubt that intervention is imperative for children living in maltreating families.*********References:Cicchetti, D., Rogosch, F. A., & Toth, S. L. (2011). The effects of child maltreatment and polymorphisms of the serotonin transporter and dopamine D4 receptor genes on infant attachment and intervention efficacy. Development and Psychopathology 23, 357-372.Van IJzendoorn, M. H., Schuengel, C., & Bakermans-Kranenburg, M.J. (1999). Disorganized attachment in early childhood: Meta-analysis of precursors, concomitants, and sequelae. Development and Psychopathology 11, 225-249.

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