Violence Alters Human Genes for Generations, Researchers Discover
In 1982, the Syrian government launched a brutal siege on the city of Hama, resulting in the deaths of tens of thousands of its own citizens in an act of sectarian violence. Decades later, the memory of this massacre was used as inspiration by rebels seeking to overthrow the Assad family, who had orchestrated the attack.
However, the impact of this violence extends beyond the immediate aftermath, leaving a lasting imprint in the genes of Syrian families. Even the grandchildren of women who were pregnant during the siege—individuals who never directly experienced the violence themselves—carry genetic markers linked to the traumatic event within their genomes.
This groundbreaking discovery offers the first human evidence of a phenomenon previously observed in animals: the transmission of stress-related genetic changes across generations. Dr. Connie Mulligan, a professor of Anthropology and the Genetics Institute at the University of Florida and the senior author of the study, emphasizes the importance of recognizing the far-reaching effects of trauma and violence on future generations.
While our genetic code remains unchanged by life experiences, our cells possess the ability to undergo epigenetic modifications in response to stress or other stimuli. These modifications involve the addition of chemical markers to genes, which can influence their activity and potentially impact how we adapt to challenging environments.
The research team, led by Dr. Mulligan, collaborated with Dr. Rana Dajani, a molecular biologist at Hashemite University in Jordan, and anthropologist Dr. Catherine Panter-Brick of Yale University, to conduct this unique study. By examining three generations of Syrian immigrants, the researchers sought to uncover the epigenetic legacy of violence within their genomes.
The study, published in the journal Scientific Reports, focused on families who had experienced the Hama siege or the more recent civil war in Syria, as well as a control group of early Syrian immigrants who had avoided exposure to violence. Through genetic analysis, the researchers identified specific epigenetic modifications linked to the experience of violence in different generations.
Notably, the grandchildren of Hama survivors exhibited 14 distinct genetic modifications associated with the trauma endured by their grandmothers. Additionally, individuals who directly experienced violence in Syria showed 21 epigenetic changes in their genomes. Furthermore, those exposed to violence in utero displayed signs of accelerated epigenetic aging, which could potentially impact their susceptibility to age-related diseases.
These findings underscore a common epigenetic response to stress, highlighting the intergenerational impact of traumatic events. Dr. Mulligan emphasizes the relevance of this research to various forms of violence, including domestic violence, sexual violence, and gun violence, urging policymakers to take a more proactive approach to addressing these issues.
While the long-term effects of these epigenetic changes remain unclear, previous studies have suggested potential links to health conditions like diabetes. By shedding light on the enduring genetic legacy of war and trauma, Dr. Mulligan and her team highlight the resilience and perseverance of the families involved in the study, underscoring the human capacity to overcome adversity.
In a world where intergenerational cycles of trauma and violence persist, this research serves as a poignant reminder of the need for greater empathy and understanding. By acknowledging the lasting impact of violence on our genes, we can work towards creating a more compassionate and inclusive society that prioritizes the well-being of future generations.
For more information, the study “Epigenetic signatures of intergenerational exposure to violence in three generations of Syrian refugees” can be found in Scientific Reports (2025).
This article was provided by the University of Florida. For more information, visit their website at www.ufl.edu.
