A new study found that exposure to domestic violence or trauma in the home may be associated with changes in a child's DNA.
Researchers at the Tulane University School of Medicine studied genetic samples from 80 New Orleans residents ages 5 to 15 and interviewed their caregivers about the home environment and exposure to specific adverse life events, including domestic violence, suicide, and incarceration of family members. Childrens' genes were analyzed to determine telomere length.
Telomeres are the sequence at the end of DNA chromosomes and are in place to prevent them from shrinking during replication. They shorten with every replication and are considered a natural marker of aging. The association between life stress and short telomeres has been well studied. Shorter telomeres are linked to poor health outcomes in adulthood, including a higher risk for obesity, diabetes, heart disease, and cognitive decline. Individuals with longer telomeres lead longer lives.
Results of this study showed an association between exposure to family stressors and shorter telomere length in children. The greater number of exposures, the shorter their telomeres. In other words, greater exposure to domestic violence and negative life stressors was associated with a genetic effect on children. This change may lead to poorer physical and mental health as adults and, ultimately, shorter life spans.
Researchers also found a gender divide in the effect of adverse events. Young girls exposed to traumatic events were more likely to have shortened telomeres than young boys in similar circumstances. Researchers controlled for factors such as socioeconomic status, parental age, child age, and maternal education. They also found that a higher level of maternal education was protective specifically for boys under the age of 10.
I would like to stress the correlation does not equal causation nature of these studies. This research does not show that domestic violence causes shortened telomeres and, by extension, shorter lives in children exposed. It does suggest that there is a correlation (or association) between exposure to violence in the home and shorter telomeres.
The psychological effect of observed violence and trauma on young children is an established phenomenon. This study reinforces that interventions in the home environment are critical to reduce the biological effect as well.
If you or someone you know is affected by domestic violence, you can contact the National Domestic Violence Hotline at 1-800-799-7233. You're not alone. It's cliche but all too true.