A recent study suggests that bullying changes the structure surrounding a gene involved in regulating mood, making victims more vulnerable to mental health problems as they age.
“Many people think that our genes are immutable, however this study suggests that environment, even the social environment, can affect their functioning,” said Isabelle Ouellet-Morin, Ph.D., a researcher at the Hôpital Louis-H. Lafontaine and professor at the Université de Montréal.
“This is particularly the case for victimization experiences in childhood, which change not only our stress response but also the functioning of genes involved in mood regulation.”
A previous study by Ouellet-Morin, conducted at the Institute of Psychiatry in London, showed that bullied children secrete less cortisol — the stress hormone — but had more problems with social interaction and aggressive behavior.
The new study indicates that the reduction of cortisol, which occurs around the age of 12, is preceded two years earlier by a change in the structure surrounding a gene that regulates serotonin, a neurotransmitter involved in mood regulation and depression.
For her study, Ouellet-Morin analyzed 28 pairs of identical twins with a mean age of 10 years. One of the twins had been bullied at school, the other had not.
“Since they were identical twins living in the same conditions, changes in the chemical structure surrounding the gene cannot be explained by genetics or family environment,” she said. “Our results suggest that victimization experiences are the source of these changes.”
The study was published in the journal Psychological Medicine.
Source: University of Montreal