The Myth of Normal 55

for certain messenger chemicals, and influencing the interactions between genes.[] Experience, in other words, determines how our genetic potential expresses itself in the end. This is what the field of epigenetics—meaning “on top of” genes—is all about. Epigenetic processes act on chromosomes, delivering and translating messages from the environment that “tell” the genes what to do. All this takes place without in any way altering the genes themselves. As the BBC’s Martha Henriques explains, epigenetics offers “a way of adapting to changing conditions without inflicting a more permanent shift in our genomes.”[2] It isn’t that genes don’t matter—they certainly do—only that they cannot dictate even the simplest behaviors, let alone account for most illnesses or address possible cures for them. Far from being the autonomous arbiters of our destinies, genes answer to their environment; without environmental signals, they could not function. In fact, life for us would be impossible if not for the epigenetic mechanisms that “turn” genes “on” or “off” in response to signals from within and from outside the body.[] Epigenetics revamps our understanding of human development from embryo to adult, and even how our species got to be here. I spoke with one of the foremost researchers in the field, Dr. Moshe Szyf, at McGill University’s storied medical school. “Evolutionary theory is a difficult one to change because it became almost religion, a religion of science,” he said. “And any questioning of it seems to be a heretical question of the whole system, which obviously it isn’t. Epigenetics doesn’t deny evolution. Epigenetics is part of evolution, but it demands a new look at how evolution works.” The new biology improves upon the standard Darwinian view of spontaneous mutations and random selection as the motors of species adaptations; it demonstrates that circumstances themselves can shape how genes adjust to the environment. Said another way, our lives are what happens when life acts upon life. Dr. Szyf and his team in Montreal performed one of the most cited epigenetic studies, with major implications for how we view development, behavior, and health. Working with laboratory rats, they examined the effect