In this article, James A. Shapiro, professor of microbiology, explains the genetic relationships between epigenetics, evolution and the environment.
“In the last blog we saw how cells keep track of invading DNA and use that information to target copies for incorporation in silent chromatin. The ability of cells to silence mobile genetic elements and other invading DNAs is a key epigenetic control process maintaining genome stability in normal times, when growth and reproduction proceed smoothly. The silent elements and other natural genetic engineering agents do not disturb a genome that is functioning well.
But what happens when the going gets tough? Do the tough get going in the genome, generating change to get out of trouble? The answer is: Yes, they do. ”