Childhood violence may accelerate the aging process

Violence experienced during childhood tends to place a toll on the child's DNA which makes them age faster than other children, researchers from Duke Institute for Genome Sciences & Policy reported in Molecular Psychiatry. Put simply, a child who experienced violence may subsequently become biologically older than his/her actual years. The researchers explained that they found DNA wear and tear normally associated with aging among some 10-year-old kids. Psychology and neuroscience post-doctoral researcher, Idan Shalev, said: "This is the first time it has been shown that our telomeres can shorten at a faster rate even at a really young age, while kids are still experiencing stress." Special DNA sequences, telomeres, are located at the ends of chromosomes - they are similar to the plastic tips of shoelaces. Telomeres stop DNA from fraying. According to recent studies, telomeres are "master integrators", connecting stress to biological age and associated illnesses. Each time cells divide, telomeres get shorter - this means that cells can only go on dividing a certain number of times. The rate of telomere loss can be accelerated as a result of psychological disorders, stress, obesity, and smoking. The authors explain that our biological age, and not just chronological age, may be reflected in the length or shortness of our telomeres. Shalev explained that prior studies had mainly focused on telomeres in adult participants, and how they reported experiences earlier on during their lives. Shalev and team gathered data on 1,100 British families with twins who were born in the 1990s, from the Environmental-Risk Longitudinal Twin Study. All the twins are now 18, but DNA samples were collected and recorded when they were five and ten years old. Data had also been gathered, through the twins' mothers, on who had experienced violence early in life, including bullying, physical maltreatment, or domestic violence. They discovered that there was more telomere loss among those who had experienced at least two kinds of violent exposures. Shorter telomeres are associated with a higher risk of developing chronic diseases and poorer survival, the authors added, which might not bode well for those children. Co-author, Avshalom Caspi, said: "Research on human stress genomics keeps throwing up amazing new facts about how stress can influence the human genome and shape our lives." The authors believe that a mechanism linking cumulative childhood stress to telomere length can lead to accelerated aging, even during childhood. "It appears to be an important way that childhood stress may get 'under the skin' at the fundamental level of our cells." Co-author, Terrie Moffitt, said: "An ounce of prevention is worth a pound of cure. Some of the billions of dollars spent on diseases of aging such as diabetes, heart disease and dementia might be better invested in protecting children from harm." The researchers say they now plan to study telomere lengths among the twins during adulthood. They also plan to measure DNA features and telomere lengths of 1,000 New Zealanders in the Dunedin Study, who have been regularly monitored since the 1970s.