ESPE Yearbook of Paediatric Endocrinology

To read the full abstract: Development and Psychopathology 2017;29:1517-1538

Work in rodents, already some years ago, showed that epigenetic changes can be transmitted trans generations. This study shows that in humans, the simple act of touching during infancy has lifelong consequences on gene expression through epigenetic changes that sustain for at least 4 years. Children who were distressed as infants and received less physical contact had a molecular profile in their cells that was underdeveloped for their age. The parents of 94 infants kept a diary of their infants' behavior (sleeping, fussing, crying or feeding) as well as the duration of caregiving that involved bodily contact at age 5-week-old. At age 4 1/2 years old, their cheek DNA was sampled. They found consistent methylation differences between high-contact and low-contact children at 5 specific DNA sites: the glucocorticoid receptor gene, nuclear receptor subfamily 3, group C, member 1 (NR3C1), μ-opioid receptor M1 (OPRM1) and oxytocin receptor (OXTR; related to the neurobiology of social bonds), and brain-derived neurotrophic factor (BDNF; involved in postnatal plasticity). Furthermore, the children who experienced higher distress and received relatively little contact had an "epigenetic age" that was lower than would be expected, given their actual age.

It is interesting to speculate what might be the consequence of these early life epigenetic changes. Another recent study (1) suggested that belief in conspiracy theories stems in part from negative early childhood experiences with caregivers!

1. Green, Douglas. Anxious attachment and belief in conspiracy theories. Personality and Individual Differences, 2018; 125: 30 DOI: 10.1016