Every generation of Jews, it is thought, must learn the trauma of the Holocaust anew from parents or community.
But a new study has provided the strongest proof yet that some of the trauma is passed along genetically, and that other genetic changes people accrue during life also get transmitted to their children.
The study, by researchers at New York’s Mount Sinai hospital, looked at the genes of 32 Jewish men and women who survived a Nazi concentration camp, witnessed or experienced torture or hid during World War II, and the genes of their children.
“The gene changes in the children could only be attributed to Holocaust exposure in the parents,” Dr. Rachel Yehuda, the head of the team of researchers, told the Guardian.
The work by Yehuda, a psychiatrist and neuroscientist, and her team is the clearest example in humans of the transmission of trauma across generations through “epigenetic inheritance” — the idea that genetic changes caused by the environment over a lifetime can be transmitted to offspring.
Genes contained in DNA are thought to be the only way to pass biological information from parent to child. But environmental influences — like smoking, diet and stress — modify genes all the time via chemical tags that attach themselves to DNA, switching genes on and off. — jta