When traumatic things happen to people of any age, it’s never good; but for children, the fallout may be even worse. A new study shows that stressful events in early life may not only affect a child psychologically, they may age children's genes, making them resemble those of someone much older.
The study followed 40 nine-year-old African-American boys. Half were from disadvantaged and half from advantaged households. The disadvantaged boys came from homes with high levels of family and economic instability. They grew up with poverty, often with single parents, and harsh parenting practices. In short, their lives had exposed them to some serious stressors from an early age.
The advantaged boys in the study did not have these types of stressors to contend with. Their economic and family lives were more stable, their mothers better educated.
Boys whose mothers had changed partners at least once, who used harsh parenting methods, and who hadn’t gone to college or who were younger, had shorter telomeres than boys from backgrounds without these issues.
Telomeres shorten each time the chromosome replicates, so over the course of a lifetime, they naturally get shorter. But other studies have found they also shorten in response to extreme stress.
That was the case with the disadvantaged boys. They had significantly shorter telomeres — about 40% shorter — than the advantaged boys. Boys whose mothers had changed partners at least once, who used harsh parenting methods, and who hadn’t gone to college or who were younger had shorter telomeres than boys from backgrounds without these issues.
Stress was only part of the story. As the researchers looked deeper, they found there were individual differences, too. Children’s existing genetic makeup also had an effect: Those with certain gene variants of the serotonin and dopamine genes, making them more susceptible to the environment, had even shorter telomeres if they came from disadvantaged backgrounds. Kids with these same gene variants, but who had more advantaged backgrounds, had the longest telomeres.
These results all suggest that the stress in a person’s environment can have a significant effect on the genes. But it's a two-way street. Our existing genetic makeup can also affect how the environment affects us, which adds an extra layer to the phenomenon.
Scientifically, the results are fascinating. But on a more personal level, the study shows how important it is to reduce kids’ stress levels as much as possible. The authors say that their results are a good argument for early intervention — if genetic changes can be illustrated as early as nine years old, it’s all the more reason to implement programs to help kids deal with stress and trauma.
Whatever kind of environment you live in, and whatever kind of stresses or traumas your child has faced, helping your child manage his or her stress is incredibly important.
The study is published in the journal Proceedings of the National Academy of the Sciences.