The phrase has become common enough to lose its edges. It’s worth being precise, because the overstated version leaves people believing they inherited damage they can’t do anything about — which is the opposite of what the evidence supports.
What plausibly transmits
Behaviour and parenting, which is by far the largest channel. A parent shaped by war, famine, persecution or displacement raises children in ways marked by it: hypervigilance, difficulty with emotional expression, an intense focus on security, a relationship to food and money formed by scarcity. Children learn from that, and pass it on.
This isn’t mysterious and it’s well documented, and it accounts for most of what is observed.
Silence and its atmosphere. A household organised around not approaching something produces children who inherit the avoidance without the content —and frequently supply a worse story than the real one.
Family narratives. What a family believes about safety, about outsiders, about what happens if you relax. These are transmitted explicitly and they’re durable.
Material circumstances. Trauma has economic consequences, and poverty and instability transmit straightforwardly.
What the epigenetics claim actually says
The popular version holds that trauma is written into DNA and inherited biologically. The research is considerably more tentative than that.
There are animal studies showing transgenerational effects, and human studies — the well-known ones on Holocaust survivors’ children and on the Dutch Hunger Winter — reporting differences in stress-related markers. They’re suggestive. They’re also small, difficult to separate from the behavioural channel, and contested among researchers.
It’s fair to say that biological transmission is plausible and unsettled. It isn’t fair to say your grandmother’s war is in your genes as an established fact, and the confident version does harm — because a thing you inherited biologically sounds fixed, and the behavioural channel isn’t.
What this means practically
The most useful implication: the main route of transmission is one that can be interrupted.
You can’t change what happened to your grandparents. You can change what happens in your house — how emotion is handled, whether things can be spoken about, what your children learn about safety. That’s where the leverage actually is, and there’s a reasonable body of work showing that the chain does break.
Recognising it in yourself
Things that make sense as a response to something that didn’t happen to you. An unshakeable sense that security is provisional. An inability to enjoy having enough. Anxiety about food, or documents, or exits. A conviction that any good period precedes a bad one. Difficulty with rest.
These frequently look irrational in your own life and entirely rational in your grandparents’.
The other half of the inheritance
Families that survived these things also transmitted the things that got them through — endurance, resourcefulness, an unusual capacity to keep functioning, and a specific kind of solidarity.
The trauma framing tends to obscure that entirely, and people arrive at this material seeing only damage. Worth naming the rest of it too.