Grandma's Experiences Leave a Mark on Your Genes

By Dan Hurley -- Discover Magazine Tuesday June 11, 2013

[This article originally appeared in print as "Trait vs. Fate"]

 Alison Mackey/Discover Magazine June 2013

Alison Mackey/Discover Magazine June 2013

Your ancestors' lousy childhoods or excellent adventures might change your personality, bequeathing anxiety or resilience by altering the epigenetic expressions of genes in the brain.

Darwin and Freud walk into a bar. Two alcoholic mice — a mother and her son — sit on two bar stools, lapping gin from two thimbles.

The mother mouse looks up and says, “Hey, geniuses, tell me how my son got into this sorry state.”

“Bad inheritance,” says Darwin.

“Bad mothering,” says Freud.

For over a hundred years, those two views — nature or nurture, biology or psychology — offered opposing explanations for how behaviors develop and persist, not only within a single individual but across generations.

And then, in 1992, two young scientists following in Freud’s and Darwin’s footsteps actually did walk into a bar. And by the time they walked out, a few beers later, they had begun to forge a revolutionary new synthesis of how life experiences could directly affect your genes — and not only your own life experiences, but those of your mother’s, grandmother’s and beyond.  

The bar was in Madrid, where the Cajal Institute, Spain’s oldest academic center for the study of neurobiology, was holding an international meeting. Moshe Szyf, a molecular biologist and geneticist at McGill University in Montreal, had never studied psychology or neurology, but he had been talked into attending by a colleague who thought his work might have some application. Likewise, Michael Meaney, a McGill 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.

 Michael Meaney, neurobiologist                                                                                          ---Owen Egan/McGill University

Michael Meaney, neurobiologist                                                                                          ---Owen Egan/McGill University

“I can still visualize the place — it was a corner bar that specialized in pizza,” Meaney says. “Moshe, being kosher, was interested in kosher calories. Beer is kosher. Moshe can drink beer anywhere. And I’m Irish. So it was perfect.”

The two engaged in animated conversation about a hot new line of research in genetics. 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. 

To read the rest of the article click here.