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

A close mother-infant relaationship is crucial for a healthy infant brain development. Biological basis of attachment behavior have began to be discovered. In animal models, like rat, the maternal care through liking and grooming determines demethylation of the glucocorticoid receptor gene (GCR) in hipotalamus and consequently an improvement in social and cognitive skills in offspring. In human, postmortem studies show a methylated GCR pattern in hipotalamus in people who commited suicide. We still, however, don't know the GCR methylation pattern in children. The aim of the present study is to look for association between methylation of GCR in human leucocytes and attachment style and trauma in children. We recruited 50 children between one to five year old with their mothers, and made interview of biographical issues to mothers and video-recorded the dyads punctuating by the CARE Index Score. Also we took blood samples to GCR methylation measure. We found an association between a high GCR methylation pattern and the presence of trauma or child abuse in infancy. This result may mean that the adverse rearing experience could epigenetically alter gene expression