The behaviours that most often lead to exclusion and victimization in the classroom or schoolyard have their roots in a student's genes, the study said, arguing that children's genetic makeup has a direct impact on the quality of the interactions they enjoy with their peers.
The findings were published on the website of the journal "Child Development."
Michel Boivin, lead researcher and psychology professor at Universite Laval, said a child's genes will often dictate the way they act, which will in turn shape their experiences both in and out of the classroom.
"We know that it's behaviour that drives the peer difficulties," Boivin said in a telephone interview from Quebec.
"It's the genetic factors that underlie the tendency to behave in a certain way that explain how the group reacts to the child and then rejects and victimizes the child."
Boivin and his colleagues studied nearly 800 pairs of both identical and fraternal twins, interviewing the students three times over a five-year period.
Researchers considered input from the students themselves, their teachers and their peers when evaluating the child`s in-school social experience. All groups were asked for input when the children were in kindergarten, Grade 1 and Grade 4.
The research showed a strong link between genetics and the child's peer interactions, Boivin said. Identical twins, who share the exact same genetic makeup, were far more likely to have a similar social experience than fraternal twins whose DNA is generally only a 50 per cent match.
Boivin stressed that researchers were not assessing the twins' individual personality traits, but were trying to evaluate the ways their classmates perceived and treated them.
"It's not a phenotype or characteristic of the child, but the characteristics of their experiences," he said.
Boivin said a child's genetic makeup lies at the root of certain behaviours that are more likely leave children on the social sidelines. He cited hyperactivity, aggression and impulsiveness as traits that are likely to alienate children.
Genetics also play a role in personal appearance, he said, acknowledging that such physical characteristics also factor into a child's social experience.
Although the research may seem to indicate that a child's peer interactions are hard-wired into their DNA, Boivin said the findings ought to send a different message to parents.
"The genes make it more likely that a child will behave a certain way and then have a certain experience, but it's not an absolute determinism," he said. "If you change the environment by intervening, then you change, eventually, the role of genes."
Boivin said parents who believe their children are exhibiting problematic behaviour would be wise to try and nip the issues in the bud at an early age, ideally during the pre-school years before a student is enrolled in kindergarten.
Limiting social ostracism would have innumerable educational and mental health benefits for the five to 10 per cent of students who report feeling marginalized in school, he said.