We inherit trauma from our parents and grandparents in much the same way we inherit our ancestors’ blood type or eye color. It may sound like something straight from a science fiction novel, but researchers have discovered that trauma actually causes measurable changes in our DNA.
Like the fight or response that triggers surges of adrenalin and other hormones, the changes in DNA are another of nature’s built-in ways of helping our body adjust and survive in periods of extreme stress.
Trauma experienced by our parents and grandparents, (and maybe even our great-grandparents), may help explain struggles with depression, anxiety, obsessions, fears, phobias, eating disorders and addiction.
Mark Wolynn, Director of the Inherited Family Trauma Center and author of the book, It Didn’t Start With You: How Inherited Family Trauma Shapes Who We Are and How to End the Cycle, calls this phenomenon the “residue from traumatic events.”
As is often the case, research begins with mice or rats. In one study, female mice exposed to trauma displayed altered DNA, thus passing the trauma along to subsequent generations who displayed marked behavioral differences when compared to the progeny of non-traumatized mice.
When sperm of traumatized male mice was injected into non-traumatized offspring, the progeny displayed similar results, including stress, anxiety and slowed metabolism. This suggests to researchers that parenting style isn’t involved, as male mice are minimally involved in care of their young.
Another study involved mice that were jolted with a mild electrical shock whenever they were exposed to the aroma of cherry blossoms. In time, the mice were trained to fear the smell even when no shock was forthcoming. Mice that weren’t exposed to electrical shock displayed no fear.
The surprising result was that the offspring of the mice, including some in subsequent generations, displayed signs of stress when exposed to the aroma of cherry blossoms.