Grandsons seem to inherit psychological stress

Traumatic experiences affect gene activity

03/12/2013

The causes of mental illness have been the subject of scientific research for decades. Psychiatrists and psychologists usually suspect the origin of depression, phobias and other mental disorders in the patient's childhood. Here it is assumed that mental injuries (traumas) that have not been sufficiently processed will not affect people later in life either „let go“ and as a result can lead to mental health problems. But not only one's own life seems to be decisive for whether a person has an increased risk for a mental illness or not. Instead, scientists have now found evidence that the biography of family members has an impact on the health of our soul.

Childhood trauma as a cause of mental disorders
What causes a mental illness? Science has been dealing with this question for decades. Up to now, it has mainly been assumed that, above all, drastic, mental injuries in childhood (so-called „trauma“) cause people to develop mental disorders - some of which only really make themselves felt in adulthood. The biography of the individual, his own experiences and the individual processing of these experiences stood at the center of the investigation.

Experiences of the ancestors leave traces in the genetic material
However, there seems to be some evidence that the lives of our direct ancestors also have an impact on our soul lives. As the American scientists Brian Dias and Kerry Ressler of the Emory University School of Medicine have found out in Atlanta, things that our grandparents experienced, for example, can also leave a mark on the heritage of their descendants. In an animal study, the researchers had given mice electric shocks to keep them away from the harmful substance acetophenone. As a result, it quickly came to the effect that the animals already jumped in fear, as soon as only the smell of organic-chemical compound came up - even without electric shock.

mice „to inherit“ learned dislike for a chemical substance
But the real surprise came when scientists next examined the next generation of mice: the descendants of the mice of the first experiment also reacted much more strongly to the smell of acetophenone than a control group - even though they themselves were never shocked by electric shock or the substance in Contact had come. But not only the next generation, but even the grandchildren of the first experimental animals showed still visible „aftermath“ their grandparents' experiences by reacting to the smell of acetophenone. The learned flinching in the smell of acetophenone had thus anchored in some way in the DNA of the animals and had been passed on to the next generation.

Traumatic experiences are on „fine structures“ saved
For the researchers a clear indication of the influence of genetics, because a passing on of experience „ Acetophenone = pain“ For example, by similar external influences revealed in further investigations, no conclusive explanation: „The fact that these changes also persist in artificial insemination, breeding of the young by foster parents and over two generations, indicates a biological origin, "said the US scientists in the journal" Nature Neuroscience " not the genes themselves affected by changes, but instead the so-called „fine structures“, which control the activity of the genes. According to the experts, traumatic experiences were apparently stored here and sometimes lead to lifelong impairments.

Results provide frameworks for further research
For researchers, this is an important step in the field of epigenetics, in which the central question is which factors are responsible for the gene activity and thus the development of the cell or whether certain changes are passed on to the next generation as in the current experiment : „Our findings provide a framework for further addressing how environmental information is inherited across generations on the behavioral, neuroanatomical and epigenetic levels“, so the researchers in the abstract of their study.

Altered activity of genes even in post-traumatic stress disorder
Also the emergence of a so-called „Post-traumatic stress disorder“ (PTSD) seems to be directly related to altered gene activity. In any case, a study by the Max Planck Institute for Psychiatry in Munich in collaboration with the Mount Sinai School of Medicine in New York, in which the psychological consequences of the terrorist attacks of September 11, 2001, is currently being investigated, comes to this conclusion.

Here it was found that those who suffer from PTSD as a result of the traumatic experience, „adaptation genes“ and „stress Gene“ have a different form of activity than healthy individuals. Accordingly, apparently, this unique experience had led to the negative experience in some of the affected people in the genetic material „burned“ and thus had far-reaching consequences for further life.

Aftermath of the „Hunger Winters“ Recognizable for generations in 1944
However, altered gene activity may not only affect the soul, but may also cause physical damage to the descendants. According to the Dutch depression researcher Florian Holsboer, this can be deduced, for example, from intergenerational epidemiological studies, in which, among other things, the health of the population was assessed during the „Hunger Winters“ Dutch born in 1944 was observed. Although children and mothers, who had suffered from extreme malnutrition and malnutrition at the time, had recovered healthily over the years, the bad experience had evidently reached the next generation „inherited“, because they also continued to give birth to underweight children with an increased risk of illness, even though they themselves had not suffered any distress. „Apparently, the genes of the grandchildren contained epigenetic markings, which are due to life experiences of the grandparents“, so the statement by Professor Holsboer in a lecture on the subject „Emergence of depression and its healing“.

Epigenetics should provide more clarity
But like that „transmission“ of traumas experienced in the genetic material of the descendants exactly works, there is still no clarity. In the next few years, therefore, information should increasingly be given to epigenetics in order to better understand what causes post-traumatic stress disorder or other mental disorders. (No)