Epigenetics has broad impact on overall health.
Identical twins Tiki and Ronde Barber have led parallel lives in football with parallel genes. Both were born premature, but grew into powerful athletes. Both attended the same college. Both served as best man at each other’s weddings. But if other studies are an indication, each man is becoming, in an epigenetic as well as career sense, less like his brother as time passes.
And although they both suffered seizures as children, as adults they are likely to come down with different illnesses. Since their genetics is unchanged, the likely culprit will be their epigenetics, quietly marking and unmarking their DNA throughout life, turning one gene on and another off. Research so far has found epigenetic clues not only to cancer, but also cardiovascular disease, diabetes, lupus, even autism. How many conditions have underlying epigenetic roots?
“We really can’t even answer that question right now,” says Tanya Hoodbhoy, PhD, of the National Institutes of Health. “That’s what we’re trying to learn.”
It seems whenever researchers look hard enough, they find epigenetics. Take, for example, the field of mental illness. In March, researchers from the Centre for Addiction and Mental Health in Canada announced the discovery of epigenetic changes in people with schizophrenia and bipolar disorder. (If one identical twin gets schizophrenia, the other twin is at 50 percent risk of the disease.) The changes appeared to occur on those genes involved in controlling chemical signals in the brain, the scientists reported in the American Journal of Human Genetics.
If epigenetics has as broad an impact on our health as many scientists think, it means that almost every aspect of our lives slowly writes our medical playbook. Doctors have long said we are what we eat. Through epigenetics, perhaps, we are also what we do.