Epigenetics, simply put, is the study of genetic and inheritable alterations that occur without a change in the DNA sequence. It differs from genetics, which refers to an individual’s genetic make-up or the study of heredity. In contrast, epigenetics deals with the way genes are expressed as a result of outside factors.
Still confused? Think of it this way: you’ve loaded a picture of yourself onto your computer. It’s not the most flattering shot, though. Your eyes are red and your nose is shiny. You look a little like a vampire with an oil-slicked nose. This needs to change. You go to your favorite photo editor and, a few strokes later, your problems are fixed. You sigh with relief. What have you done? Without changing the shape, size, or other aspects of your image, you’ve altered its appearance. It’s still you, but different.
Outside factors such as the environment, age, diet, stress, or even certain activities can similarly change how your genes behave.
One type of epigenetic change is possible through a process called methylation, when clusters of hydrogen and carbon (i.e. methyl groups) attach themselves to DNA. By covering up part of the genetic code, they can either suppress or
activate the way genes express themselves, acting like on-off switches.
Another way epigenetic change can occur is through transposons, which copy sections of genetic code and then attach themselves elsewhere. Vast changes can result. Scientists dubbed one well-researched line of fruit flies referenced in Tangled Roots “Methuselah” because a transposon had dramatically increased its life span.
Why is epigenetics important? Scientists think that, by carefully altering the way certain genes are expressed, certain diseases can be treated. Great, right? But could epigenetics be used to bring about other changes such as enhancing positive genetic traits? Could human strength, speed, intelligence, or a score of other variables be tweaked to create “better” people? Such speculation stirs up knotty moral problems, particularly considering the giant income disparity in today’s world; what might become available to some would be totally unavailable to the vast majority. Still, it’s fun to imagine. Check out my story, “The Gift,” to see one way epigenetics changes the lives of a whole society.