"Genetic and Environmental Factors in the Relationship Between Trauma
E xposure and Response"

Understanding the relationship between factors that predispose to exposure to trauma, and factors that influence response to trauma is important for both research and clinical purposes. Using data collected from relatives, it is possible to begin to disentangle seemingly confounded phenomena such as event exposure and response. A constraint on the measurement of response to trauma (e.g., PTSD) is that it is only possible among those who have experienced trauma. This situation typically makes it impossible to assess the covariation between trauma exposure and response. However, data collected from relatives offer a partial solution to this problem, because it is possible to examine the rates of PTSD in pairs concordant vs. discordant for event exposure. This type of modeling is explored with data collected from MZ and DZ twins, in order to partition genetic from environmental factors in trauma response. Alternative approaches, including measured genetic factors, comorbid conditions and other covariates are also considered.