Researchers find genetic link to children's emotional problems precipitated by bullying
22 July 2010
Researchers at the Institute of Psychiatry (IoP) at King’s and Duke University (US) have discovered a genetic variation that moderates whether victims of bullying will go on to develop emotional problems.
Gene and environment interactions are a burgeoning area of scientific research and an increasing body of evidence demonstrates that children who are victims of bullying are at risk of developing emotional problems including depression. However, not all children who are bullied go on to develop such problems. Whether a gene variant could contribute to emotional disturbance in children who are bullied is the focus of the study reported in the Journal of the American Academy of Child and Adolescent Psychiatry.
Dr Karen Sugden at the IoP, and colleagues, report on the findings in a study sample of 2,232 same-sex five year-old twins. Home visit-assessments were conducted in 1999-2000 when the children were five years of age, and follow-up assessments were made at 12 years of age. The children were evaluated for emotional problems reported by their mothers and teachers. In addition to interviews, DNA samples acquired via buccal swabs were evaluated to determine the presence or absence of the genetic variation under investigation.
The researchers observed that genetic differences in the 5-HTTLPR gene, specifically the SS genotype, interact with bullying victimization to exacerbate emotional problems. The strength of this genetically influenced response is related to the frequency of the bullying experience; the gene and environment interaction being strongest for frequently bullied children.
Dr Sugden said: 'This genetic moderation persists after controlling for children’s previctimization emotional problems and for other risk factors shared by children growing up within the same family environment. Our findings are consistent with previous studies that indicate that SS genotype victims of relational aggression are prone to depression.
'Our research could lead to public health interventions, for example greater efforts to decrease bullying, that may lower the prevalence of child psychopathology,' she concluded.
This study was supported by the UK Medical Research Council grants and National Institutes of Health (USA).
The study entitled, 'The Serotonin Transporter Gene Moderates the Development of Emotional Problems Among Children Following Bullying Victimization' is published in the Journal of the American Academy of Child and Adolescent Psychiatry (August 2010) and online at www.jaacap.org