BOB HIRSHON (host):
Beyond D-N-A. I’m Bob Hirshon and this is Science Update.
You may have been told that your D-N-A is the blueprint for who you are. But this is only part of the story, says geneticist Rob Martienssen of Cold Spring Harbor Laboratory.
ROB MARTIENSSEN (Cold Spring Harbor Laboratory):
In recent years we found that in addition to the DNA there are modifications of that DNA and those modifications could be just as important as the genes themselves.
These modifications, called the epigenome, are made by chemicals that latch on to the D-N-A. Martienssen and others are urging the creation of an international Human Epigenome Project, which will map the roles that these chemicals play. Unlike the genome, the epigenome changes over time, which explains why identical twins grow less alike as they age and why older people are more prone to disease.
I’m Bob Hirshon, for AAAS, the science society.