Can we inherit our parents’ trauma? Research points to yes.
“Real true, posttraumatic stress disorder [PTSD] is going to have an impact, certainly on the next generation and maybe generations after that,” said Rachel Yehuda, PhD.
Yehuda, in the Educator of the Year Lecture at the 2022 Annual Psychiatric Times™ World CME Conference in San Diego, shared her research on the potential of PTSD being passed genetically through the generations. Studying the Holocaust and 9/11 survivors showed fascinating results.
At a clinic for Holocaust survivors and their families at Mount Sinai School of Medicine, families reported feeling damaged, guilty, anxious, full of morbid grief, and had dysfunctional interpersonal relationships due to fear of loss. Overall, the children of survivors believed that parental Holocaust exposure was involved in their current mental health problems.
Previous research by Yehuda et al showed adult offspring of Holocaust survivors had differential effects of maternal and paternal PTSD in both glucocorticoid receptor sensitivity and vulnerability to psychiatric disorder. With both maternal and paternal PTSD, offspring had lower GR-1F promoter methylation; with just paternal PTSD, offspring had GR-1F promoter hypermethylation.1 Furthermore, Holocaust exposure induced intergenerational effects on FKBP5 methylation; specifically, Holocaust survivors and their adult children showed a nongenotype dependent change in methylation compared to their respective controls.2 This was the first demonstration of an association of preconception parental trauma with epigenetic alterations that is evident in both exposed parent and offspring.
Similar findings resulted from Yehuda’s work on the effects on 9/11. For example, in a post-9/11 program surveilling women who were pregnant, Yehuda and researchers collected salivary cortisol from mothers and babies.3 “What we found is that the mothers that felt PTSD, their cortisol levels were lower, but it’s also lower in babies, which was really wild,” said Yehuda. “But here’s the kicker: Both cortisol levels are lowest in the babies of mothers with PTSD who were exposed in the third trimester.”
This research suggests maternal PTSD may confer additional in utero effects, causing more anxiety for example.3 Trauma exposure during pregnancy directly affects the fetus and fetus germ cells, Yehuda shared.3
How does trauma pass down? Yehuda explained that epigenetic changes could survive cell division associated with the formation of sperm and eggs; if the parent is exposed to trauma, their exposure could result in epigenetic changes that may affect their sperm or egg—meaning a single trauma could simultaneously affect multiple generations without direct exposure.
“This is inherited in our DNA,” said Yehuda. “Trauma is inherited.”
The biological remnants of parental experiences in our DNA can affect us in multiple ways, according to Yehuda. They can influence our response to stressors/challenges, make us better able to detect and respond to threats, increase vulnerability to mental health disorders, and increase our attunement to injustice. They are enduring, but not irreversible, Yehuda stressed.
1. Yehuda R, Daskalakis NP, Lehrner A, et al. Influences of maternal and paternal PTSD on epigenetic regulation of the glucocorticoid receptor gene in Holocaust survivor offspring. Am J Psychiatry. 2014;171(8):872-880.
2. Yehuda R, Daskalakis NP, Bierer LM, et al. Holocaust exposure induced intergenerational effects on FKBP5 methylation. Biol Psychiatry. 2016;80(5):372-380.
3. Yehuda R, Engel SM, Brand SR, et al. Transgenerational effects of posttraumatic stress disorder in babies of mothers exposed to the World Trade Center attacks during pregnancy. J Clin Endocrinol Metab. 2005;90(7):4115-4118.