Research dating back to the 1950s had shown that rats handled by humans for as little as five to 15 minutes per day during their first three weeks of life grew up to be calmer and less reactive to stressful environments compared with their non-handled littermates.
Seeking to tease out the mechanism behind such an enduring effect, Meaney and others established that the benefit was not actually conveyed by the human handling.
Likewise, Michael Meaney, a Mc Gill neurobiologist, had been talked into attending by the same colleague, who thought Meaney’s research into animal models of maternal neglect might benefit from Szyf’s perspective.“I can still visualize the place — it was a corner bar that specialized in pizza,” Meaney says. Since the 1970s, researchers had known that the tightly wound spools of DNA inside each cell’s nucleus require something extra to tell them exactly which genes to transcribe, whether for a heart cell, a liver cell or a brain cell.
According to the new insights of behavioral epigenetics, traumatic experiences in our past, or in our recent ancestors’ past, leave molecular scars adhering to our DNA.The methyl group works like a placeholder in a cookbook, attaching to the DNA within each cell to select only those recipes — er, genes — necessary for that particular cell’s proteins.Because methyl groups are attached to the genes, residing beside but separate from the double-helix DNA code, the field was dubbed epigenetics, from the prefix (Greek for over, outer, above).And for those unlucky enough to descend from miserable or withholding grandparents, emerging drug treatments could reset not just mood, but the epigenetic changes themselves.Like grandmother’s vintage dress, you could wear it or have it altered.A January storm has deposited half a foot of snow outside the picture windows lining his fourth-floor corner office at the Douglas Institute, a mental health affiliate of Mc Gill.He has the rugged good looks and tousled salt-and-pepper hair of someone found on a ski slope — precisely where he plans to go this weekend. “I’ve always been interested in what makes people different from each other,” he says.In a landmark 1997 paper in , he showed that natural variations in the amount of licking and grooming received during infancy had a direct effect on how stress hormones, including corticosterone, were expressed in adulthood.The more licking as babies, the lower the stress hormones as grown-ups.The genome has long been known as the blueprint of life, but the epigenome is life’s Etch A Sketch: Shake it hard enough, and you can wipe clean the family curse.Voodoo Genetics Twenty years after helping to set off a revolution, Meaney sits behind a wide walnut table that serves as his desk.