ANAHEIM, CA In studies on cancer, heart disease, neurological disorders and other degenerative conditions, some scientists are moving away from the "nature versus nurture" debate, and are finding you're not a creature of either genetics or environment, but both - with enormous implications for a new approach to health.
The new field of "epigenetics" is rapidly revealing how people, plants and animals do start with a certain genetic code at conception. But, the choice of which genes are "expressed," or activated, is strongly affected by environmental influences. The expression of genes can change quite rapidly over time, they can be influenced by external factors, those changes can be passed along to offspring, and they can literally hold the key to life and death.
According to Rod Dashwood, a professor of environmental and molecular toxicology at the Linus Pauling Institute at Oregon State University, epigenetics is a unifying theory in which many health problems, ranging from cancer to cardiovascular disease and neurological disorders, can all be caused at least in part by altered "histone modifications," and their effects on the reading of DNA in cells.
"We believe that many diseases which have aberrant gene expression at their root can be linked to how DNA is packaged, and the actions of enzymes such as histone deacetylases, or HDACs," Dashwood said. "As recently as 10 years ago we knew almost nothing about HDAC dysregulation in cancer or other diseases, but it's now one of the most promising areas of health-related research."
In the case of cancer, tumor suppressor genes can cause cancer cells to die by acting as a brake on unrestrained cell growth. But too much of the HDAC enzyme can "switch off" tumor suppressor genes, even though the underlying DNA sequence of the cell its genetic structure has not been changed or mutated. If this happens, cells continue to replicate without restraint, which is a fundamental charact
|Contact: Nicole Kresge|
Federation of American Societies for Experimental Biology