A new study published by a group of American scientists has found a link between the trauma suffered by Jewish Holocaust survivors during World War II and genetic differences in their children, Maariv reported on Sunday. 

A team of researchers, led by Rachel Yehuda of Mount Sinai Hospital in New York, traced the stress hormone of 32 Holocaust survivors who were imprisoned in Nazi concentration camps or were forced into hiding during the war. 

The genes of the survivors’ children were also tested and compared with the genes of Jewish families who lived outside of Europe during the Second World War. 

According to the findings, the environmental impact of the Holocaust created genetic changes in survivors. These changes were then transferred to the second generation, who have an increased risk of developing post-traumatic stress disorder. 

“The genetic changes in children can only be explained because of their parents’ exposure to the Holocaust,” Yehuda argued. 

The study, which was published in Biological Psychiatry, is considered the first conclusive case of trauma being transferred from parent to child, and reinforces the scientific theory that environmental influences also affect future generations.