For many coffee lovers, their precious beverage comes with an unwanted ingredient: caffeine. As a result, processes have been developed to remove the compound, although current methods are expensive and sometimes compromise flavor. But scientists may have come up with a way to get decaffeinated coffee straight from the plant. Researchers report today in the journal Nature that their genetically modified coffee plants have 70 percent less caffeine than regular plants do.

Three enzymes are involved in making caffeine in coffee plants. Researchers at the Nara Institute of Science and Technology in Japan led by Shinjiro Ogita engineered seedlings of Coffea canephora in which expression of the gene controlling one of these enzymes--theobromine synthase, or CaMXMT1--was repressed. Compared with regular plants, leaves from one-year-old GM plants exhibited a 50 to 70 percent reduction in caffeine content. According to the report, "the transgenic plants described here should yield coffee beans that are essentially normal apart from their low caffeine content at maturity."

The scientists note that their technique could sidestep some of the problems of industrial decaffeination, in which solvents flush caffeine from the beans. Their next step is to apply their technique to C. arabica plants, which produce the high-quality Arabica coffee that accounts for 70 percent of the world market. Of course, it remains to be seen if java lovers will embrace "GM joe."