By Laura Sanders When sociologist Mike Tomlinson began combing through the health records of people in Northern Ireland, he wasn’t interested in suicide. He was on the hunt for links between poverty and international conflict. But he came across a startling trend. From 1998 to 2008, the rate at which men in their mid-30s to mid-50s were committing suicide rose alarmingly fast, more quickly than the rate for the rest of Northern Ireland’s population. At first, that spike made no sense. A peace agreement reached in 1998 transformed Northern Ireland into a prosperous and tranquil place. Economic indicators had been surprisingly good. Suicide rates in neighboring countries were all gently falling. Nothing seemed to explain why so many of these men were killing themselves. But Tomlinson found a hint in the men’s pasts. They had all grown up in the late 1960s and the 1970s, during some of the worst violence Northern Ireland had ever experienced. Called the Troubles, this warlike period brought religious and political fighting that pitted neighbor against neighbor. Children of the Troubles lived with terrorism, house-to-house searches, curfews and bomb explosions. Trauma early in life had rendered men more vulnerable to taking their own lives later, Tomlinson proposed in July in International Sociology. “If you were younger then, you carry that through,” says Tomlinson, of Queen’s University Belfast. This idea, that something that happened long ago could have such a profound effect today, seemed to resonate with others. When he described his idea to a suicide prevention group in Northern Ireland, “they just lit on it, and said it speaks so much to what they were seeing.” © Society for Science & the Public 2000 - 2012

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 11: Emotions, Aggression, and Stress
Link ID: 17391 - Posted: 10.20.2012

By Tina Hesman Saey Identical twins aren’t perfect carbon copies of each other even at birth. Twins emerge from the womb carrying different chemical marks on their DNA that influence the activity of individual genes, a new study shows. Known as epigenetic markers, these alterations don’t change the underlying genetic information. But by regulating the activity of certain genes, they can profoundly influence how the DNA blueprint is used to create and operate a living organism. Past research has shown that identical twins bear some differences in epigenetic markers. But those differences were thought to arise after birth, as twins have different life experiences and encounter different environments. The new study — the first to measure epigenetic profiles in newborns — suggests that subtle differences in conditions within the womb can leave marks on fetal DNA that may have long-term consequences for adult health. These differing chemical tags may help explain why identical twins look slightly different, have their own personalities and may have different susceptibility to diseases. Jeffrey Craig, a molecular and cell biologist at Murdoch Childrens Research Institute in Parkville, Australia, and his colleagues report the findings online July 15 in Genome Biology. Identical twins are on average more epigenetically similar than fraternal twins, the researchers found. The similarity was probably not due to sharing a womb, but could be attributed partially to genetics and partially to chance, they suggest. © Society for Science & the Public 2000 - 2012

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 17054 - Posted: 07.18.2012