Intergenerational Trauma: Can the Pain of Our Ancestors Be Inherited?

Wars, famines, and political repression don’t just damage the people who live through them. A growing body of research suggests that the consequences of collective trauma can echo for decades—showing up in the children and grandchildren of survivors. But what exactly gets passed down? Biological changes, behavioral patterns, or family stories? And where is the line between a scientifically documented phenomenon and the metaphor of “ancestral trauma”?

What Epigenetics Has to Do With Trauma

Epigenetics studies changes in how genes are expressed—without altering the DNA sequence itself. The most studied mechanism is DNA methylation: the addition of methyl groups to specific regions of the genome, which can turn genes on or off. Stress, hunger, and violence can trigger such changes, and recent research suggests that some of these epigenetic marks may persist in reproductive cells and be passed to the next generation.

The key system researchers focus on is the hypothalamic-pituitary-adrenal (HPA) axis, which regulates the body’s stress response. Chronic stress and trauma are linked to altered methylation of genes that control this system—particularly FKBP5 and NR3C1. These genes frequently appear in studies of descendants of people who survived traumatic events.

What Human Studies Have Shown

The longest-running observation of intergenerational effects is the Dutch Hunger Winter of 1944–1945. Children of women who were pregnant during the famine showed lasting epigenetic changes, including altered methylation of the IGF2 gene, which regulates growth. Some studies have found metabolic and epigenetic differences in grandchildren as well, though the effects were weaker and their interpretation remains debated. A 2024 study of 944 survivors found accelerated biological aging and a metabolic profile resembling multiple chronic diseases.

Studies of Holocaust survivors’ descendants have revealed alterations in cortisol regulation and FKBP5 methylation compared with control groups. Children of survivors with PTSD showed lower cortisol levels and increased glucocorticoid receptor sensitivity. A 2025 study of 371 participants—descendants in the third and fourth generations—found a more complex picture: they had epigenetic patterns linked to enhanced oxytocin system activation (social bonding) alongside changes in HPA-axis genes (heightened stress reactivity). Yet their level of psychopathology was not elevated.

In 2025, Scientific Reports published the first study of an intergenerational epigenetic signature of violence across three generations of Syrian refugees. Among 131 participants from 48 families, researchers found differentially methylated positions associated with both direct and germline (passed through reproductive cells) exposure to violence. Most of these positions showed unidirectional methylation changes, suggesting a common epigenetic response to violence.

Psychological Mechanisms: Not Just Biology

But reducing trauma transmission to epigenetics alone would be an oversimplification. Psychological research highlights the role of family environment and parenting practices. A 2024 study of Hungarian Holocaust descendants (599 children and 311 grandchildren) found that the intensity of parental coping styles related to past trauma predicted the level of adaptive effort and psychiatric symptoms in offspring—and the mechanism appeared similar for the second and third generations. This means trauma is also transmitted through behavior: overprotection, anxiety, and emotional closedness in parents can affect children regardless of biological mechanisms.

A 2024 Norwegian study across three generations (Tromsø Study data) confirmed the “additive risk hypothesis”—but only for maternal grandparents. Neglect by maternal grandparents was associated with a higher likelihood of depression in grandchildren, even after accounting for parental neglect. This further points to the special role of the maternal line in intergenerational transmission.

The Limits of the Concept of “Ancestral Trauma”

It’s important to understand that “ancestral trauma” is not a scientific term but rather a metaphor. Scientists speak of intergenerational transmission of trauma effects, emphasizing that what is passed down is not the memories or emotions themselves, but a biological predisposition and/or behavioral patterns. Demonstrating true germline transmission of epigenetic states in humans requires ruling out alternative explanations: shared genetic variants, shared postnatal environment, and behavioral transmission of traumatic reactions.

“Intergenerational trauma is not mysticism, and it’s not a life sentence,” says Dmitry Kazankov, founder and CEO of Family-Tree. Online. “Research shows that biological and psychological traces can indeed be passed down, but the epigenome is plastic. When a family reconstructs its history, builds a family tree, and talks through difficult chapters, that can change the trajectory. We see this in practice: people who start exploring their family history often find an explanation for their own reactions for the first time—and a resource to break the cycle.”

The Bottom Line

Intergenerational transmission of trauma is a real, scientifically documented phenomenon—but it’s more complex than the simple formula “genes remember pain.” Epigenetic mechanisms, family environment, and parenting strategies all play a role. Understanding these mechanisms matters not for fatalism, but for conscious work with family history: recovering ancestral memory and giving voice to traumatic experience can be a first step toward breaking the intergenerational cycle.