Cultureplaces

Click on this link for the documentary which is no longer available from the BBC https://dailysong.net/watch/x30x4tk/the-ghost-in-your-genes-horizon-discoverysciencebiology-docu.html

The children of people who have experienced extremely traumatic events are more likely to develop mental health problems. And new research shows this is because experiencing trauma leads to changes in the sperm. These changes can cause a man’s children to develop bipolar disorder and are so strong they can even influence the man’s grandchildren. Psychologists have long known that traumatic experiences can induce behavioural disorders that are passed down from one generation to the next. However, they are only just beginning to understand how this happens. Researchers at the University of Zurich and ETH Zurich now think they have come one step closer to understanding how the effects of traumas can be passed down the generations.

Both positive and negative experiences influence how genetic variants affect the brain and thereby behaviour, according to a new study. "Evidence is accumulating to show that the effects of variants of many genes that are common in the population depend on environmental factors. Further, these genetic variants affect each other," explained Sheilagh Hodgins of the University of Montreal and its affiliated Institut Universitaire en Santé Mentale de Montréal. "We conducted a study to determine whether juvenile offending was associated with interactions between three common genetic variants and positive and negative experiences." Hodgins and her colleagues published the study on December 11, 2014 in the  International Journal of Neuropsychopharmacology.