What are the salivary DNA methylation differences associated with war exposure in Syrian refugee children and adolescents?
Children living in war-torn countries not only suffer mental health issues but may also be left with biological changes at the DNA level that could have lifelong health impacts, according to new research.
Researchers analyzed DNA in saliva samples from 1,507 Syrian refugee children, aged 6 to 19, living in informal settlements in Lebanon and reviewed questionnaires completed by the children and their caregivers that asked about the child’s exposure to war-related events.
Children who had been exposed to war events showed multiple changes in DNA methylation, a chemical reaction that leads to genes being turned on or off.
Some of the changes were linked to genes involved in critical functions such as nerve cell communication and transport of materials within cells, the researchers said.
These particular changes have not been seen in other forms of trauma, like poverty or bullying, suggesting that war may trigger unique biological responses, they also said.
While both boys and girls were affected, girls showed stronger biological responses to war exposure, suggesting they may be more vulnerable to the long-term effects of trauma at a molecular level.
"While it's common knowledge that war harms the mental health of children, our study has found evidence of the biological mechanisms underlying this effect,” study leader Michael Pluess of the University of Surrey in the UK said in a statement.
Pluess also noted that gene expression in war-exposed children was not aligned with what would be expected for their age groups, “which could mean that war could be impacting (their) development.”
Despite the researchers' attempts to capture the severity of war exposure, "it is likely that this approach does not fully appreciate the complexity of war” or the impact of repeated war events on children, the researchers concluded in a report published on Wednesday in JAMA Psychiatry.
Some 400 million children worldwide are living in or fleeing from conflict zones, the United Nations Children's Fund estimates.