Offspring of stressed mice show symptoms

A woman's risk of anxiety and dysfunctional behavior may depend on the experiences of her parents, particularly fathers, when they were young, U.S. researchers say. A study in mice conducted by scientists at Tufts University School of Medicine suggests stress caused by chronic social instability during youth contributes to epigenetic changes in sperm cells that can lead to psychiatric disorders in female offspring across multiple generations. "The long-term effects of stress can be pernicious," Tufts researcher Lorena Saavedra-Rodriguez said. "We first found that adolescent mice exposed to chronic social instability, where the cage composition of mice is constantly changing, exhibited anxious behavior and poor social interactions through adulthood. These changes were especially prominent in female mice." Further study involving the offspring of these previously stressed mice found that female, but not male, offspring exhibited elevated anxiety and poor social interactions. But even though the stressed males did not express any of these altered behaviors, researchers said, they passed on these behaviors to their female offspring after being mated to non-stressed females. "We are presently searching for biochemical changes in the sperm of stressed fathers that could account for this newly appreciated form of inheritance," senior study author Larry A. Feig said. "Hopefully, this work will stimulate efforts to determine whether similar phenomena occur in humans."