Why does long-term exposure to extreme stress make some people more resilient, while it makes others weaker? Does such an experience result in far-reaching biological changes that can be transferred to future generations? More than seventy years after WWII many of these questions remain unanswered.
Now a team of Czech Researchers at CEITEC (Central European Institute of Technology) of Masaryk University in Brno are addressing some of these issues in a study focusing on Holocaust survivors and their children. I spoke to the head of the research team prof. Ivan Rektor about the aim of the project and what it involves.
“We are interested in the transfer of the consequences of the horrible experience to the second and third generation, i.e. to the offspring of Holocaust survivors. It has been well-known that the children of Holocaust survivors may suffer –and sometimes suffer - from “Holocaust survivor children’s syndrome”’. They are more sensitive to stress, can suffer from emotional misbalance, are more prone to post-traumatic stress disorders and so on. This is well-known, but what is not clear is whether this transfer to the second generation is a social/behavioural transfer or a biological, genetic, epigenetic transfer. We are studying this question.”
How is the research being done?
“We are studying three generations in the family of a Holocaust survivor: the survivor, their children and grandchildren. We want to compare the acquired data with the data of people whose families did not go through such a terrible experience.”
So you have volunteers? I understand you give them questionnaires, you do brain scans – is that right?
“Yes. First of all we are studying the level of stress in the three generations and a control group. But we are also studying post-traumatic growth, using questionnaires. Post-traumatic growth means, that a certain person after exposure to stress, may present some growth, they become stronger. So we are looking at these two types of reactions to stress: post-traumatic stress disorders or post-traumatic growth. And we study biological markers. We perform MR scans of these people aiming to see whether there is an epigenetic transfer of this experience.”
Why does such an experience make some people stronger and some people weaker? And can they influence it, by their attitude?
“It is well-known that the children of Holocaust survivors are more prone to suffer from post-traumatic stress disorders.”
“I don’t know whether we can influence it or not, we probably can’t influence which kind of response will occur. With our research, we hope to predict the kind of response by finding the neurobiological factors underlying different responses. Of course, after having done the diagnosis, for example for post-traumatic stress disorder, there is a possibility to treat the person.”
Do women respond differently from men? Or children from adults? Have you ascertained any differences?
“From literature, we know that there are differences between how women and men respond. But as regards young and old -our group of Holocaust survivors- they were all very young –or young -at the time of exposure. Also the experience they had during the war was very different. Some of them were in Auschwitz, others were in Terezin, many of the survivors were hidden or else they fought, they were partisans in Slovakia. So we need to collect as much data as possible from as many people as possible to have a reasonable cohort of people in order to distinguish the types of reactions, depending on the type of experience.”
And would it make a difference, whether the person was active or whether they were held captive and unable to influence their fate?
“I don’t know, it is one of the questions that we would like to answer. But most of the survivors were children during the war so they didn’t have the choice to fight. We will see how many first generation people we can get data from and whether we will have enough people from the various subgroups to reach such conclusions.”
You said it had been proven that somehow this stress is transferred to second generation family members. What do we know about that?
“It was published many times that the children of Holocaust survivors suffer from disorders or are more prone to suffer from post-traumatic stress disorders. For example, there are specialized psychotherapy centres; one of them is in Prague, the Rafael Institute, that treat the second generation.”
Do you think that it is genetically transferred or that it is socially transferred?
“That is exactly the question that we are raising. It has been shown already that there is a certain genetic transfer, it was reported on in a study by Yehuda. So there are certain genetic transfers of stress. We are looking at so-called telomeres. Telomeres are the endings of chromosomes and it is known that they get shorter with age, but also with stress. We want to see whether this occurs in the second and the third generation. What is also new in our study is that we are not only looking at post-traumatic stress but also post-traumatic growth and we want to see whether there is an epigenetic transfer of this type of reaction as well.”
Would it not depend on what kind of person it is? Whether they are naturally optimistic, more resilient?
“We are talking about the first generation, I assume. This probably played a role, but it is hard to study it now, after so many years. But to survive the Holocaust, to survive Shoah; the probability was low. So personality traits might have contributed to survival in certain cases. An Israeli study comparing Holocaust survivors with people who lived in Israel and Palestine during the war and were not exposed to the Holocaust, showed that the people who survived the Holocaust lived longer than the other group. So it seems that the probability of surviving the Holocaust was related to personality traits.”
If you manage to ascertain whether –or to what extent -the transfer is genetic or social, then will you be able to prevent it? What is the aim of the study? Will you be able to do something about it if you know more?
“We are not only looking at post-traumatic stress, but also post-traumatic growth and we want to see whether there is an epigenetic transfer of this type of reaction as well.”
“At this moment we can’t prevent it. But it could be used in recent conflicts or conflicts occurring right now, for instance in the former Yugoslavia or currently in Syria. If we really find the neurobiological markers related to a certain kind of response to stress, indicating whether a person is at risk from post-traumatic stress disorder, or if it is more probable that the reaction will be post-traumatic growth, we could diagnose persons at risk and treat them at an early stage, for instance by psychotherapy. Or consider the social aspects, in the event of a possible social transfer. And there is the third generation, we are also studying the grandchildren – little is known about how it effects them. The studies and treatment generally focus on the second generation. But the third generation – or at least some of them - might also suffer from the Holocaust survivor syndrome. But so far this hasn’t been studied so much.”
The changes in the brain must go very deep to be able to affect another two generations...
“That is epigenetics. This means that it is a modification of genetic information that is transferred. It’s probable that the changes go very deep. But we also need to consider the social transfer, the behaviour of parents which influences the behaviour and the responses of their children and grandchildren. So that is what we are studying –the epigenetic transfer but also the social transfer.”
How do you ascertain the social transfer? By asking them questions?
“Yes, by asking them questions.”
To what extent would you say that this happens? Because most survivors don’t talk about their experience, they don’t like to remember it. You very often hear from their children that they never speak about it.
“This is very different and depends on the personality. Some of them don’t speak, others do. But the social transfer is not necessarily by telling the children about the experience, it may also be a non-verbal transfer. We are now at the beginning of the study, we hope to answer a series of questions, but we do not have the answers just yet.”
Are you cooperating with other scientists and researchers abroad?
“No, we aren’t. We approached several scientists in Germany, where there is a centre like ours, but we started alone, hoping to get some collaboration on the way. We have very well equipped laboratories, including two MR machines, we have a very good neuroscientists and geneticists, a very skilled team. So it occurred that several factors came together; a good laboratory a good team, motivation. And we started because the first generation (survivors) is dying out.”
So nothing like this has been done anywhere before?
“Not in this complexity.”
How long will the research take and do you have enough volunteers?
“We are hoping to get a grant, but if we do not get it, we will continue with the project anyway, focusing on the first generation. We have many volunteers from the second generation, we haven’t focussed much on the third generation, because of the time constraints. So far we have recorded data from 100 people, including 30 from a control group (those who did not undergo a harrowing experience). From the first generation we recorded 17 survivors plus 13 controls. Regarding the third generation, we hope to collect data also from survivors in Prague, because the possibilities in Brno are already exhausted.”
How long did you say the project would take?
“I think we can get the first data within a year, but the analysis and writing papers on it will take at least three years.”