There’s hurt people who hurt people, and then there’s damage that alters your DNA.
Generational trauma has become a popular topic of conversation. Many believe that groups of people who survive trauma could pass on both mental and physiological illnesses to their children. Trauma can include famine, genocide, enslavement, war, or personal harm. The theory is that people pass on trauma through their chemically altered genes, even if those children don’t ever experience the same stressors.
How Generational Trauma Works
Renowned psychiatrist Dr. Carl Jung first coined the term “collective unconscious” in the early 1900s. He defined it as a “reservoir of shared unconscious wisdom and ancestral experience that entered consciousness only in symbolic form to influence thought and behavior.”
In other words, the context of a shared history can shape how future generations react to their environments. If one generation experiences a trauma firsthand, they may develop thought patterns that they pass on to future generations. Individuals may pass on these psychological patterns to their children—like catastrophizing, which is when you have anxiety because your mind is imagining the worst-case scenario—perpetuating the cycle.
Beyond psychology, there’s also new DNA evidence of inherited trauma. This is thanks to epigenetic studies, which is the research of how genes are expressed.
These studies show that both an affected parent and their offspring have two signs of inherited trauma:
- More glucocorticoid receptors (GR): These are responsible for rapid shut downs of stress responses. Receptors are like mailboxes in your body. They receive messages from neurotransmitters that tell your body what to do, how to react, etc. Someone who has more GRs will react differently to stress than someone with fewer GRs.
- Less DNA methylation in the part of the brain that promotes GR: DNA methylation controls how genes are expressed.
To put it another way, the DNA might not mutate. Instead, trauma may modify the chemical genetic marker that helps read DNA. This change can alter coping methods in response to stressors (like a parent's absence). Plus, trauma may “turn off” certain genes. However, the studies also show that “nurturing the paternal environment" could reverse these changes for both the parent and child. Examples might include removing or addressing daily stressors and receiving physical, mental, and/or emotional support (which in humans could translate to going to counseling).
To be fair, most scientific studies test this theory on mice or worms. However, they do show that the offspring of mice who experience trauma show similar altered behaviors. Epigenetics is a fast-growing line of research and there is always more to be explored.
Examples Throughout History
The post-traumatic stress disorder (PTSD) that many soldiers develop after combat has had more time in the spotlight due to the wide-ranging effect it has on people of all races and ethnicities. Children of veterans with PTSD may struggle with similar mental health challenges as their parent(s).
There is some research that backs up this theory—for instance, in comparing the mental health of veterans’ children who were born before versus after their time in combat. Some studies show that certain behavioral and environmental interventions can help reverse the trauma's potentially negative effects. One way to do this might be introducing the parents to a more positive environment (by perhaps dealing with the trauma, or improving their socioeconomic status) before having kids.
Today’s discourse also centers around other communities, including those who have endured:
- Slavery (such as Black Americans)
- Internment (such as Japanese Americans)
- Genocide (such as Indigenous Americans or victims of the Holocaust)
- Natural disasters (such as survivors of Hurricane Katrina in New Orleans or Hurricane Maria in Puerto Rico)
- Displacement due to war or famine (such as refugees from Southeast Asia, the Middle East, and parts of Africa)
In these communities, generational trauma has created a potential obstacle for descendants. It may increase the likelihood of continued suffering from PTSD, depression, and substance misuse. In some cases, it may be a barrier to acquiring wealth and finding opportunities to improve their overall health and wellness.
Understanding generational trauma is the first step. The next step is to help break this cycle. One way to do this is by practicing medicine with empathy for the challenges that different racial and ethnic communities have faed throughout history. Learn more about how cultural respect can lead to better health care here.
- Collective unconscious. Britannica. (Accessed on August 31, 2021)
- Parents' emotional trauma may change their children's biology. Studies in mice show how. Washington, DC: Science Magazine, 2019. (Accessed on August 31, 2021)
- Can the legacy of trauma be passed down the generations? London, UK: BBC Future, 2019. (Accessed on August 31, 2021)
- Can Trauma Be Passed Down From One Generation to the Next? Psycom, 2020. (Accessed on August 31, 2021)
- Youssef NA, Lockwood L, Su S, Hao G, Rutten BPF. The Effects of Trauma, with or without PTSD, on the Transgenerational DNA Methylation Alterations in Human Offsprings. Brain Sci. 2018 May; 8(5): 83.
- Traces of Genetic Trauma Can Be Tweaked. New York, NY: Scientific American, 2017. (Accessed on August 31, 2021)
- The Mind's Hidden Switches. New York, NY: Scientific American, 2011. (Accessed on August 31, 2021)
- Gapp K, Bohacek J, Grossmann J, et al. Potential of Environmental Enrichment to Prevent Transgenerational Effects of Paternal Trauma. Neuropsychopharmacology. 2016 Oct; 41(11): 2749–2758.
- The Human Genome Project. Bethesda, MD: National Human Genome Research Institute. (Accessed on August 31, 2021)
- The legacy of trauma. Washington, DC: American Psychological Association, 2020. (Accessed on August 31, 2021)