New genetic score reliably predicts risk and severity of youth depression

An international team led by Munich researchers has discovered a genetic score that reliably predicts the risk, severity and age of onset of depression in young people. The study also confirms the history of abuse in childhood as a risk factor.

According to the World Health Organization, depression is now the leading cause of disability, affecting more than 300 million people worldwide. Depression is a disease resulting from interactions between biological, psychological and social factors. Although depression can occur at any age, it often begins in early adolescence. Identifying the risk factors for depression before symptoms of clinical confusion occur is crucial for targeted and effective prevention strategies.

A study published by a team of the Max Planck Institute of Psychiatry Munich and the Ludwig-Maximilians-Universitaet (LMU) of the Munich Medical Center, in collaboration with researchers from Emory University (Atlanta, United States). USA), the University of Coimbra (Portugal) and the University of Helsinki (Finland) bring us closer to the possibility of preventing depression in children and adolescents. The authors used a relatively new method of calculating the genetic risk of depression. Traditional genetic studies focus on one genetic difference at a time and determine its statistical badociation with the risk of disease. In this study, information derived from numerous genetic variants badociated with depression, identified in a sample of more than 460,000 adults, was used to create a score reflecting the aggregate genetic risk of depression, also known as the polygenic risk score. Individually, these variants have little impact on risk but, taken together, they may reveal an otherwise hidden disease risk, thus providing a much clearer picture. The method has already been used successfully to quantify the genetic risk for many common diseases, such as heart disease or diabetes.

The study appears in the American Journal of Psychiatry, the newspaper most read by psychiatrists and mental health professionals. Thorhildur Halldorsdottir, first author of the study, explains how this has been done in more detail: "The score was first calculated from genetic data obtained from a very large number of adults with depression.This parameter was then evaluated in smaller cohorts of children and adolescents.Determine whether it was possible to predict depression and symptoms of depression in this age group. "In addition, she studied the impact of an environmental factor – child abuse – likely to predict depression. "We also looked at how a history of child maltreatment had affected the risk.We found that the polygenic risk score and the exposure to abuse were useful information to identify young people at risk. risk of depression. "

Elisabeth Binder, director of the Max Planck Institute and head of the department in which this research was conducted, summarizes the results as follows: "This is the first study that shows that the polygenic risk score calculated from Depressed adults can be used to: identify children at risk of developing depression, before the onset of any clinical symptom. "

Effective psychological and pharmacological interventions against depression are already well known. A combination of these interventions has proven to be the most effective. Unfortunately, the implementation of these measures is not feasible in the field of public health, partly because of lack of resources. Gerd Schulte-Körne, Director and Chair of the Department of Psychiatry for Children and Adolescents, Psychosomatic and Psychotherapy at the LMU Medical Center, adds: "By applying the results of studies such as this one, it should be possible to The future of: targeting young people at highest risk of depression, ie those with a high polygenic risk score and / or a history of childhood violence, to these effective interventions. "

Binder concludes: "There is still a lot of work to be done to perfect the early identification of young people at risk of depression, but identifying the children most likely to develop depression would give us the opportunity to implement it. prevention strategies and reduce the enormous health burden of depression. "