Dr. Rachel Yehuda’s is a pioneer in the study of stress, trauma, and epigenetics. She has discovered that trauma survivors can leave biological markers in their offspring’s genes. These markers appear to be associated with parents' experience of extreme stress. But this field is relatively new, with more research needing to be done, so today we talk about stress and then delve into the possible theories behind the science, what these theories might mean, and why this kind of biological effect could be a strength. Rachel Yehuda is the Director of the Traumatic Stress Studies Division at the Mount Sinai School of Medicine.