Association between maternal care an glucocorticoid receptor gene methylation in human leucocytes

A close mother-infant relationship is crucial for a healthy infant brain development. Biological basis of attachment have began to be discovered. In animal models, like rat, the maternal care through liking grooming determines demethylation of the glucocorticoid receptor gene (GCR) in hypotalamus and a consequence improve in cognitive and social behavior in offspring. In humans, a few postmortem studies show a similar pattern of methylation on people who commited suicide. The aim of the present study is to look for association between methylation of GCR on leucocytes and attachment style and trauma in children. We recruited 50 children between one to five years old with their mothers, and made interview of biographical issues to mothers and video-recorded the dyads puntuating with the CARE Index instrument. Also we took blood samples for GCR methylation measure. We found an association between a methylated pattern of GCR and the presence of trauma or child abuse in infancy. These results may mean that adverse rearing experience could epigenetically alter gene expression.