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. 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 Mc Gill 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. So it was perfect.” The two engaged in animated conversation about a hot new line of research in genetics.
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).
Originally these epigenetic changes were believed to occur only during fetal development.
But pioneering studies showed that molecular bric-a-brac could be added to DNA in adulthood, setting off a cascade of cellular changes resulting in cancer.
Sometimes methyl groups attached to DNA thanks to changes in diet; other times, exposure to certain chemicals appeared to be the cause.
Szyf showed that correcting epigenetic changes with drugs could cure certain cancers in animals.