This"mantled" fruit failed to produce much oil, creating a vexing problem. Because the abnormality shows up in genetically identical clones, "it's impossible to attack genetically," an approach often taken when a crop has a bad trait that can be bred out of that variety, says study co-author Robert Martienssen, a plant geneticist at the Cold Spring Harbor Laboratory in New York.
Plant geneticist Ravigadevi Sambanthamurthi and her colleagues at the Malaysian Palm oil Board in Selangor have been trying to understand why supposedly identical trees don't all produce equally good fruit for 30 years. More than a decade ago, they began collaborating with Martienssen and other scientists to sequence the oil palm genome, which was completed 2 years ago. With the genome in hand they were in a better position to start evaluating the "epigenome," chemical modifications to DNA that also affect how and when genes work Already Martienssen's team had developed a way to assess one such modification, called methylation, of the genome of Arabidopsis, a fast-grower that scientists often study in the lab to learn basic plant biology.