Epigenetics - the study of changes in gene expression that don’t alter the DNA sequence. Some theories suggest these effects, like those from stress or trauma from specific experiences, may be passed down not through DNA, but through RNA, an older and more flexible regulatory system.
My first memory is from June 24, 1941, in Kovno, Lithuania. The only problem is, I was born more than sixty years later. Technically, the memory isn’t mine. It belongs to my grandfather, Aba Gefen. But in many ways, it feels like it’s mine too.
My grandfather was a Holocaust survivor. Just days after the Nazi invasion of Kovno, he was rounded up with twenty other Jews and taken to the city square, where they stood under threat of execution. He narrowly escaped death when a woman named Zina Blumenthal intervened and claimed he was part of her family. Zina, a photographer, was married to a highly decorated Lithuanian colonel who, because of his status, had received permission to leave the area. As she scanned the square, she noticed my grandfather, who had rented a room in her family’s home. She recognized him and insisted that he be released as well, explaining he was a relative. In doing so, she risked her life and saved his.
I heard the story about Zina Blumenthal countless times as a child, so many times that, at some point, it stopped feeling like someone else’s memory. I could see the square clearly in my mind, picture Zina’s kind face, and imagine the dignified presence of her decorated husband, Colonel Adolf Blumenthal. It was as if the memory had settled into me, not just as a story passed down, but as something I somehow remembered myself. And the strangest part is that a few years ago, I visited that very square for the first time, and it looked exactly as I had imagined it in my mind’s eye. I had never been there before. I had never even seen a photo.
That moment made me wonder: maybe something in my grandfather’s memory was so fundamental, so deeply etched, that it didn’t just pass down through his words, but through the body itself?
Later, when I began studying cognitive neuroscience, I discovered that there are actually theories that speak to this very idea.
One of the most intriguing theories in neuroscience today comes from a field called epigenetics. This theory suggests that life experiences such as trauma, stress, or hunger might be inherited across generations. It’s important to say from the start that this idea is considered by many scientists to be controversial, and there is no clear evidence that it happens in humans. But a few studies in animals, especially in worms, it seems that certain experiences appear to leave molecular imprints that affect the next generation.
Professor Oded Rechavi and his team at Tel Aviv University showed that when worms were exposed to viral infection or starvation, they produced small RNA molecules in response. These molecules did not disappear after the initial threat was gone, but instead were passed on to their offspring, who exhibited altered gene expression and behavior even without being exposed to the original stimulus. This suggests that some acquired traits, such as reactions to stress or environmental cues, might be biologically recorded and transmitted through epigenetic pathways. This suggests that some life experiences might be stored in the body and passed down in a biological way, not by changing the DNA itself, but through small RNA molecules that control which genes are active. These molecules can carry information from one generation to the next, shaping how the offspring respond to the world around them.
A talk by Prof. Oded Rechavi exploring how acquired experiences can be inherited through RNA molecules, and influence the behavior of the next generation.
So is it possible that a traumatic event like the one my grandfather experienced that day in Kovno was passed down to me as a memory? Science is still far from showing such a phenomenon in humans, and it it will be difficult to determine such a thing. First of all, scientists cannot perform such experiments on humans, both for ethical reasons and because they require long timespans, often several generations.
Still, some interesting studies have been done. For example, research on people born after the Dutch Hunger Winter of 1944 has shown that children of those who experienced famine during pregnancy had higher risks of health problems, including altered stress responses. This suggests that extreme experiences can leave lasting biological traces across generations. But this also raises a deeper question: what is a memory, really? Is it a vivid experience I can consciously recall, or something less visible, an imprint I do not remember, yet still shapes how I feel, react, and behave?Whether my grandfather’s memories were passed down to me biologically or simply through behavior and family stories, I have no doubt that they continue to shape who I am to this day. The knowledge that an act of kindness can save a life feels deeply embedded in my body.
And perhaps that is the most powerful lesson epigenetics can offer us: that a single decision made by a woman named Zina Blumenthal in June 1941 continues to echo through generations of a family, even today.
P.S. For anyone interested in reading more on this topic, I highly recommend Judith Shulevitz’s fascinating piece “The Science of Suffering” — a powerful deep dive into the biology and legacy of intergenerational trauma.
