The scientists say what is most significant about the new study, described online September 16 in Nature Neuroscience, is that for the first time DNA methylation "tagging" has been linked to something at the behavioral level of a whole organism. On top of that, they say, the behavior in question, and its corresponding molecular changes, are reversible, which has important implications for human health.

According to Andy Feinberg, M.D., M.P.H., Gilman scholar, professor of molecular medicine and director of the Center for Epigenetics at Hopkins' Institute for Basic Biomedical Sciences, the addition of DNA methylation to genes has long been shown to play an important role in regulating gene activity in changing biological systems, like fate determination in stem cells or the creation of cancer cells. Curious about how epigenetics might contribute to behavior, he and his team studied a tried-and-true model of animal behavior: bees.

Working with bee expert Gro Amdam, Ph.D., associate professor of life sciences at Arizona State University and the Norwegian University of Life Sciences, Feinberg's epigenetics team found significant differences in DNA methylation patterns in bees that have identical genetic sequences but vastly different behavioral patterns.