Rebellious kids more likely to have shorter telomeres: Results show that three-year-old children, mothers of whom suffered from major depression, had shorter telomeres as compared to children of non-depressed mothers tested at ages four and five.

Preschool children who exhibit rebellious and disobedient behavior are more likely to have shorter telomeres – the ‘aging’ biomarkers of our cells. In adults, this characteristic of cellular aging is known to be associated with an increased risk of chronic diseases – diabetes, obesity and cancer included.

The study, conducted by UCSF researchers and published in the journal Translational Psychiatry, also discovered that a history of clinical depression in mothers was an independent predictor for shortened telomeres in adolescents.

Telomeres are ‘caps’ at the ends of chromosomes. They exhibit a buffering effect against the loss of protein-coding DNA during cell division. Telomere shortening is a natural process and occurs as cells age. However, elaborate research indicates that the process is substantially accelerated in cases of biological and psychological stress.

“These are the first steps in a new field aiming to understand early determinants of children’s telomeres. There are not any studies yet that examine telomere length changes from birth to adulthood, so the long-term implications are unknown,” stated lead author Janet Wojcicki, PhD, Assistant Professor in the UCSF Department of Paediatrics. “In adults, however, short telomeres predict earlier onset of many diseases, and shorter telomere length likely tracks from childhood throughout life.”

Wojcicki’s team of researchers analyzed the length of telomeres obtained from white blood cells of a reasonably homogenous sample of low-income Latino children. These included four year olds (108) and five year olds (92) who were enlisted from two hospitals in San Francisco.

Many of the five year olds were the same children who were initially tested the year before. Behavioural disorders, such as disobedience, hostility, lack of compliance and irritability were also looked in children aged three, four and five. Furthermore, the researchers assessed the telomeres of the children’s mothers and conducted screening for prenatal or postnatal maternal depression.

Results revealed that three-year-old children, the mothers of whom suffered from clinical depression (major depression), had shorter telomeres as compared to children of non-depressed mothers tested at ages four and five. However, mild symptoms or major postnatal or prenatal depression were not found to be related with telomere length. Children with behavioural problems at ages three, four or five had shorter telomeres partially due to maternal depression, and their mothers also had comparatively shorter telomeres. This may be attributed to stress and genetics.

These findings somewhat corroborate other studies which show that shorter telomere lengths in children and adults are correlated to early childhood trauma, violence and deprivation. While the study shows evidence of how maternal depression influences a child’s physical and physiological health, there is room for more research to fully understand the impact of this phenomenon on children’s cell aging.

“These findings underscore the importance of intervening early to address behaviour issues in children as well as to treat maternal depression.” explained Wojcicki. “While long-term studies are needed, our results suggest that maternal mental health issues and child behavioural problems can impact children at the cellular level.”

“Currently there are far more questions than answers about the myriad factors that shape and promote healthy telomere maintenance in early childhood. We may be catching a small glimpse of the intergenerational transmission of health,” stated senior author Elissa Epel, PhD, from the UCSF Department of Psychiatry.