Abused children are at higher risk for anxiety and mood disorders because traumatic experiences can have a long-term impact on their gene regulation. Scientists at the MaxPlanck Institute for Psychiatry in Munich have found for the first time that a variant in the FKBP5 gene is able to influence epigenetic changes in this gene induced by early trauma. Individuals who are genetically predisposed to trauma can cause long-term alterations in the methylation of their DNA, leading to long-term dysregulation of the stress hormone system. As a result, these affected individuals can find themselves less able to cope with stressful situations and may develop depression, post-traumatic stress syndrome or anxiety disorders in adulthood. The researchers hope that these findings will help develop new individualized treatment strategies and increase public awareness of child protection. Many human diseases stem from the interaction of individual genes and environmental influences. Childhood trauma is a high risk factor for future psychiatric disorders. The research team tested the DNA of nearly 2,000 people who had suffered repeated and severe trauma in adulthood or childhood. As a result, one-third suffered from post-traumatic stress syndrome. The risk of post-traumatic stress syndrome increased with increasing levels of psychological abuse in people who carried a genetic variant of FKBP5, which determines the body’s response to stress and, by doing so, regulates the entire stress hormone system. By comparing DNA sequence variations in trauma-experienced individuals with and without the disease, it is possible to understand the mechanisms of interaction between genetic environments.