‘Second genetic code’ discovered

Molecular genetic researchers at U.Va. have discovered a new area outside the DNA itself that may show existence of another type of genetic code.

In four articles published in the Aug. 10 issue of the journal Science, C. David Allis, U.Va. Byrd Professor of Biochemistry and Molecular Genetics, other U.Va. researchers and collaborators at the National Institutes of Health and Cold Spring Harbor Laboratory in New York, as well as the Research Institute of Molecular Pathology at the Vienna Biocenter in Austria, describe how proteins called histones, around which the DNA is coiled, form a structure called chromatin and provide sites where additional gene regulation appears to occur, acting, in effect, as a master “on/off” switch.

Allis and other researchers have co-authored several studies that show evidence that histone methylation is at the heart of this common on/off switch.

“We believe that what is telling the cell to make those choices is an overall code that may significantly extend the information potential of the genetic DNA code itself. For some time, we have known that there is more to our genetic blueprint than DNA itself. We are excited that we are beginning to decipher a new code, what is referred to as an epigenetic histone code.

“If we know how to control which genes we want to turn on or off, we might be able to reduce disease risk,” Allis said. “For example, we could turn off genes that promote tumor growth, to help prevent cancer development, and turn on other genes that suppress tumors.”