leo_m_chalupa's picture
Neurobiologist; Professor of Pharmacology and Physiology, George Washington University

Epigenetics is a term that has been around for more than a century, but its usage in the public domain has increased markedly in recent years. In the last decade or so there have been dozens of articles in newspapers (notably the New York Times) and magazines, such as the New Yorker, devoted to this topic. Yet when I queried ten people working in the research office of a major university, only one had a general sense of what the term meant, stating that it deals with “how experience influences genes.” Close enough, but the other nine had no idea, despite the fact that all were college graduates, two were lawyers and four others had graduate degrees. Not satisfied by the results of this unscientific sample, I asked an associate dean of a leading medical school how many first-year medical students knew the meaning of this term. He guessed that the majority would know, but at a subsequent lecture when he did a polling of fifty students, only about a dozen could provide a cogent definition. So there you have it, another example of a lack of knowledge by the educated public of a hot topic among the scientific establishment.

What makes epigenetics important, and why is it so much in vogue these days? Its importance stems from the fact that it provides a means by which biological entities, from plants to humans, can be modified by altering gene activity without changes in the genetic sequence. This means that the age-old “nature versus nurture” controversy has been effectively obviated because experience (as well as a host of other agents) can alter gene activity, so the “either/or” thinking mode no longer applies. Moreover, there is now some tantalizing, but still preliminary evidence that changes in gene activity (induced in this case by an insecticide) can endure for a number of subsequent generations. What happens to you today can affect your great, great, great grandchildren!

As to why epigenetics is a hot research topic, the answer to that is that major progress is being made in the underlying mechanisms by which gene activity can be modified by specific events. Currently, more than a dozen means by which gene expression or gene repression occurs have been documented. Moreover, epigenetics processes have been linked with early development, normal and pathological aging, as well as several disease states, including cancer. The hope is that a fuller understanding of epigenetics will enable us to control and reverse the undesirable outcomes, while enhancing those that we deem beneficial to us and to future generations.