ZURICH, SWITZERLAND—The children living in SOS Children's Villages orphanages in Pakistan have had a rough start in life. Many have lost their fathers, which in conservative Pakistani society can effectively mean losing their mothers, too: Destitute widows often struggle to find enough work to support their families and may have to give up their children.

The orphanages, in Multan, Lahore, and Islamabad, provide shelter and health care and send kids to local schools, trying to provide "the best possible support," says University of Zurich (UZH) physician and neuroscientist Ali Jawaid. "But despite that, these children experience symptoms similar to PTSD [post-traumatic stress disorder]," including anxiety and depression.

Beyond these psychological burdens, Jawaid wonders about a potential hidden consequence of the children's experience. He has set up a study with the orphanages to probe the disturbing possibility that the emotional trauma of separation from their parents also triggers subtle biological alterations—changes so lasting that the children might even pass them to their own offspring.

That idea would have been laughed at 20 years ago. But today the hypothesis that an individual's experience might alter the cells and behavior of their children and grandchildren has become widely accepted. In animals, exposure to stress, cold, or high-fat diets has been shown to trigger metabolic changes in later generations. And small studies in humans exposed to traumatic conditions—among them the children of Holocaust survivors—suggest subtle biological and health changes in their children.

[Click here to read the rest of the article.]