Reuters

September 3, 2001

Environmentally Friendly Modified Tomato?

LONDON, England (Reuters) -- German scientists have developed a genetically modified tomato which they say is environmentally friendly and could be used to deliver vaccines and antibodies. The tomato has been engineered in such a way that it will not pass on its genes to other crops -- something that is a concern in most genetically modified genetically modified, or GM, crops. Its creators also believe the new technology could be used to develop fruit and vegetables that could help immunize against certain diseases.

"In a way you can call it a breakthrough that really opens up a lot of new applications," Professor Ralph Bock, who headed the research, said in a telephone interview Friday. Bock developed the plant with a team at the Institute of Plant Biochemistry and Biotechnology in Munster.

Using a new technology, the scientists inserted a foreign gene into the chloroplast of the plant cell instead of into the nuclear DNA or genome, the conventional way of genetically altering plants. The chloroplast, which is similar to the mitochondria or powerhouse of animal cells, has a separate small genome. Bock said it was much more difficult to put genetic material into the chloroplast genome, but there were a number of advantages.

One of these is that the foreign DNA in the chloroplast cannot be transmitted by pollen, so it will not contaminate neighboring plants.

Much of the fear surrounding GM crops is the danger they pose to non-GM crops. Inserting the foreign gene in the chloroplast also allows scientists to produce more proteins in the plants. Bock, a plant microbiologist, said it could lead to edible plants that can be used to deliver vaccines, drugs and antibodies into the body. "You can have the plant produce vaccines which can be orally taken up with the food to give immunization to certain diseases," said Bock, whose research is reported in the journal Nature Biotechnology. "In the future we will probably collaborate with industrial partners," he added.

Pal Maliga, a professor at Rutgers University in New Jersey, described the work as a milestone. "The capacity to express foreign proteins at a high level in a consumable fruit should open new opportunities for engineering the next generation of medicinal products that are more palatable to the consumer," Maliga said in a commentary on the research.

So far only a marker gene has been inserted into the plants to show the technique works. Until now the technology had only been used in tobacco plants, which are not edible. Bock and his team have filed for a patent on the technology. They are currently working on plants that produce vitamins and in the future they hope to produce vaccines in tomatoes. The team collaborated on the research with scientists at the University of Sao Paulo in Brazil.