Evidence of domestic violence or trauma can show up in the DNA of children.
A new study shows that children in homes affected by violence, suicide, or the incarceration of a family member have significantly shorter telomeres—a cellular marker of aging, than those in stable households.
Telomeres are the caps at the end of chromosomes that keep them from shrinking when cells replicate.
Shorter telomeres are linked to higher risks for heart disease, obesity, cognitive decline, diabetes, mental illness, and poor health outcomes in adulthood.
For a new study, published online in the journal Pediatrics, researchers took genetic samples from 80 children ages 5 to 15 in New Orleans and interviewed parents about their home environments and exposures to adverse life events.
“Family-level stressors, such as witnessing a family member get hurt, created an environment that affected the DNA within the cells of the children,” says lead author Stacy Drury, associate professof of psychiatry and behavioral sciences and director of the Behavioral and Neurodevelopmental Genetics Laboratory at Tulane University.
GIRLS AFFECTED MORE THAN BOYS
“The greater the number of exposures these kids had in life, the shorter their telomeres were—and this was after controlling for many other factors, including socioeconomic status, maternal education, parental age, and the child’s age.”
Gender moderates the impact of family instability, the study shows. Traumatic family events were more detrimental to young girls as they were more likely to have shortened telomeres.
There was also a surprising protective effect for boys: mothers who had achieved a higher level of education had a positive association with telomere length, but only in boys younger than 10.
Ultimately, Drury says, the study suggests that the home environment is an important intervention target to reduce the biological impacts of adversity in the lives of young children.
《The Association of Telomere Length With Family Violence and Disruption》, Published on Journal 《Pediatrics》in June 2014.