Few things play a bigger role in a child’s development than the bond with their mother in their early days. But it turns out that the strength of that bond is determined genetically. Such are the results of an international study involving over 400 mother-child pairs. Scientistscollected genetic information and behavioral data from the infants. Half of the mothers received mentoring to improve attachment with their children. Study results showed that formation of secure attachment to their mothers was largely affected by a certain serotonin transporter gene, SLC6A4, which has a long and a short form. Children with the short form of the gene whose mothers received attachment mentoring were almost four times more likely to be securely attached at 18 months than children carrying the short form whose mothers did not receive mentoring. But children with the long form of the gene were mostly unaffected by their mother’s training. These results can help develop more effective parenting interventions based on genetic analysis.


Barak Morgan, Robert Kumsta, Pasco Fearon, Dirk Moser, Sarah Skeen, Peter Cooper, Lynne Murray, Greg Moran, Mark Tomlinson

Canadian author:

Greg Moran, Department of Psychology, Western University, London, ON, Email: gmoran2@uwo.ca

Original paper published in PLOS Medicine on February 28, 2017.