The amount of comforting contact an infant receives can lead to epigenetic changes that are detectable 4-5 years following infancy, according to findings published last week in the journal Development and Psychopathology.
While similar results have been found in animal studies, the University of British Colombia and BC Children’s Hospital Research Institute Team wanted to test if this could be replicated in a human study.
The study involved 94 healthy children in British Columbia. Starting at 5 weeks of age, parents of the children were asked to keep a diary of the infants’ behavior (such as sleeping, fussing, feeding or crying) and describe the duration of caregiving that involved bodily contact. At 4 ½ years of age a cheek swab was done to obtain DNA samples of the children.
The researchers analyzed the extent of DNA methylation in these samples. They found consistent differences between the high and low contact children at five specific sites, two of which fall within genes. One of the genes plays a role in the immune system and the other in metabolism, though the effects of these changes on later development are not currently known. Children with higher distress and lower contact had an “epigenetic age” that was lower than expected. Other recent studies have linked such discrepancies to poor health.
The team plans to continue their study to see what effects these epigenetic changes have on long-term psychological development and health.