How is trauma transmitted from generations? Epigenetics, at least in my eyes, is a professional explanation how familyconstellations work.

The human body is an amazing machine that does a multitude of things. It allows us to conceive, then build, spaceships that can travel to the distant reaches of the solar system.

It allows us to smell a rose or to run a marathon. We can do these things, and so much more, because our bodies are made up of trillions of specialized cells that get their marching orders from DNA - our genes. Geneticists used to think humans were stuck with the genes that our parents gave us. We now know we can change them without changing our DNA sequence. This insight has given rise to a new science - epigenetics.

What Bert Hellinger started on a psychological level already has a scientific explanation for all those who are deeply interested in how trauma can be transmitted from one generation to another. Ongoing research explores how epigenetic mechanisms interact with genetic variation, aging, disease, and environmental factors. Understanding these interactions will lead to breakthroughs in diagnostics, therapeutics, and disease prevention.

All human characteristics, including psychological ones, are influenced to some extent by genetics.

There are two ways to influence the next generation — at least. One way is to directly transmit something that you have, and you transmit it in the form that you have it. So let’s say a change has been made onto your DNA — an epigenetic mark now sits on a promoter region of your gene, for example. And through the magic of meiosis, that mark gets transmitted through the act of reproduction. The cell divides, there’s reproduction, and the change sticks, and it’s present in the next generation. That’s one thing. That’s a transmitted change.

There’s another kind of change that involves giving your child — either at conception or in utero or post-conception — a set of circumstances, and the child is forced to make an adaptation to those circumstances.

Each person´s DNA lays the groundwork for the development of physical and psychological characteristics - providing complex instructions for the creation of proteins and other molecules. But the manner in which these instructions are used can be modified by various factors. The chemical modifications that influence gene activity in this way are collectively called the epigenome.

These modifications occur naturally and help to steer development - for example, they enable cells in the brain and in other parts of the body to perform specialized roles based on the same underlying genetic code. But the epigenome is also susceptible to influence by exposure to toxins and other environmental factors.

Epigenetic changes do not actually change the underlying DNA sequence of genes. Instead, they involve the  attachment  of chemical compounds to the DNA. (The prefix “epi-” means “above” or “upon.”) One major type of epigenetic mechanism, called DNA methylation, occurs when molecules called methyl groups attach to certain pieces of DNA. This may render a gene inactive—preventing the creation of proteins based on the gene - by physically blocking off the DNA and through other, less direct effects. Methylation can activate genes as well. Epigenetic changes also include modifications to the histone proteins around which DNA molecules are wound, along with other kinds of alternations.

All human characteristics, including psychological ones, are influenced to some extent by genetics. Since the epigenome modulates the effects of an individual´s genome -and because it can be influenced by external factors - it is naturally a major area of exploration for those seeking to understand how individual differences, mental illness and other aspects of cognitive life take shape.

Behavioral geneticists and behavioral epigeneticists are scientists who investigate whether epigenetic changes can help account for vulnerability to certain forms of mental illness. Another possibility that has received  attention  in recent years is that epigenetic changes resulting from  traumatic  experiences can be passed from one generation to the next, sometimes called intergenerational transmission of trauma.

Severe stress early in life, some research suggests, may result in epigenetic changes that contribute to a  lasting increase in one’s physiological stress response . Such an effect could reflect a mechanism for adapting to a threatening environment based on early experience. But when the source of stress, such as early mistreatment, does not continue indefinitely, a bolstered stress response could prove harmful in the long term.

The hope is that as we learn more about the ways catastrophic experiences have shaped both those who lived through those horrors and their descendants, we will become better equipped to deal with dangers now and in the future, facing them with resolution and resilience.

If you are interested in this topic, in my next blog you can read a very interesting interview with my favorite American neuroscientist and epigeneticist Rachel Yehuda, who a pioneer in understanding how environmental and behavioral experiences can transmit effects at a cellular level and across generations.

Alexandra Alexander