NEW YORK — Ten years ago, when researchers completed the first map of all the genes of human beings, the immense undertaking promised to revolutionize the field of molecular medicine. It did, but something was still missing.
By sequencing the 3 billion chemical base pairs that make up human DNA, scientists were able to glean new information about genes and how they are expressed. Yet there were hints that something else might be controlling which genes are turned on and off, said Jean-Pierre Issa, director of the Fels Institute for Cancer Research and professor of molecular biology at Temple University in Philadelphia.
"When the human genome was sequenced, some scientists were saying, 'That's the end. We're going to understand every disease. We're going to understand every behavior.'" Issa said. "And it turns out, we didn't, because the sequence of the DNA isn't enough to explain behavior. It isn't enough to explain diseases."
For the rest of the story: http://www.livescience.com/37135-dna-epigenetics-disease-research.html