Depression through trauma in childhood

Trauma in childhood burns into the genetic material

03/12/2012

Traumatic childhood experiences, such as violence, abuse or tragic deaths, result in a significantly increased risk of mental illness later in life. An international research team led by Elisabeth Binder of the Max Planck Institute for Psychiatry Munich has now decrypted a molecular effect that causes this increased susceptibility to mental illness.

According to the researchers, childhood traumas and the high levels of stress associated with them lead to permanent changes in the regulation of genes. „Some variants of the FKBP5 gene are epigenetically altered by early trauma“, What „in people with this genetic predisposition a permanent dysregulation of the stress hormone system“ causes, reports the Max Planck Institute for Psychiatry in a recent press release. The results of their research have the scientists in the journal „Nature Neuroscience“ released.

Lifelong impairments due to traumatic childhood experiences
The abuse and violence experiences in childhood can affect the affected person for a lifetime, has long been known. The increased susceptibility to mental illnesses such as depression or phobias has also been discussed many times in this context. But so far, possible molecular connections have been left out. The international research team led by Elisabeth Binder has therefore examined the genetic material of nearly 2,000 African Americans as part of a comprehensive study, „who were severely traumatized several times as adults or as children“, reports the Max Planck Institute. Around one third of the subjects were mentally ill and showed a posttraumatic stress disorder as a result of the events that had taken place, while the other study participants were apparently better able to process their traumatic experiences. The scientists compared the genetic sequences of diseased and unaffected trauma victims to „the mechanism of this gene-environmental interaction“ clarify and find out which genetic effect is behind the increased risk of disease.

Special gene variant causes an increased risk of mental illness
Actually that is „Risk of developing posttraumatic stress disorder with increasing severity of maltreatment only in the carriers of a specific genetic variant in the FKBP5 gene“ According to the report of the Max Planck Institute of Psychiatry. Only subjects with a corresponding genetic predisposition showed a significantly higher disease risk after traumatic events in childhood. The variant of the FKBP5 gene thus forms the key to the increasingly occurring mental illness after childhood trauma experiences. The gene „Determines how effectively the body can respond to stress hormones, thereby regulating the entire stress hormone system“, the Max Planck Institute explained the function of FKBP5.

Genetic changes due to childhood trauma
The scientists showed in experiments on nerve cells that „extreme stress and thus high levels of stress hormone a so-called epigenetic change“ effect the FKBP5 gene. So be „At this point, a methyl group cleaved, which significantly increases the activity of FKBP5“, explains the Max Planck Institute of Psychiatry. The effect is primarily due to trauma in childhood. Study participants who were traumatized exclusively in adulthood showed accordingly „no disease-associated demethylation in the FKBP5 gene.“ The scientist of the Max Planck Institute for Psychiatry, Torsten Klengel, who also participated in the study, explained that traumas in childhood leave permanent traces on the DNA, depending on their genetic predisposition. Due to the epigenetic changes in the FKBP5 gene „a persistent dysregulation of the stress hormone axis in the affected person“ conditionally, in the worst case „can end up in a psychiatric illness.“ According to the expert is one of the key findings of the current study, „that the stress-induced epigenetic changes can only occur, even if this particular DNA sequence“ present.

New treatment strategies for mental illness after childhood trauma
The results of the researchers are on the one hand an important contribution to the „Understanding of psychiatric disorders as a result of the interaction of environmental and genetic factors“, On the other hand, however, they can also help „Individualized treatment of people in whom, above all, a traumatization in early youth has significantly increased the risk of disease“, reports the Max Planck Institute for Psychiatry. „This identification of molecular mechanisms of genotype-related long-term environmental reactivity will be useful in designing effective treatment strategies for stress-related disorders“, the researchers write in that „Nature Neuroscience“-items.

However, the current findings also raise the question of whether the epigenetic changes caused by the child's trauma may also be passed on to the children of the affected trauma victims. This must now be investigated in further studies. In addition, there is hope on the part of the researchers to be able to undo the underlying processes with drugs in the future, which should also be checked in future investigations. (Fp)

Also read:
The agony of memories of trauma
Brain damage from mistreatment in childhood
Child maltreatment leaves scars in the brain
Higher risk of disease due to trauma

Picture: Martin Schemm