Engineered but not GMO?; Finding a pothole on the TRAIL
A new gene modification technology has opened the possibility of engineering plants without the introduction of foreign transgenes. But the impact of the technology on the GMO debate can't be ascertained because GM opponents say it has not yet hit their political radar.
In the May issue ofNature Biotechnology, researchers from Pioneer Hi-Bred International Inc. reported the use of RNA/DNA chimeric oligonucleotides to introduce a single point mutation into the acetohydroxyacid synthase (AHAS) gene in corn at a position known to confer resistance to imidazolinone herbicides. The resulting corn plants were resistant to such herbicides, leading the researchers to suggest that oligonucleotide-mediated gene modification, which does not involve genomic integration of transgenes, can be applied to crop improvement.
Pioneer Hi-Bred (Des Moines, Iowa), a subsidiary of DuPont Co. (DD, Wilmington, Del.), has a non-exclusive license to the chimeric oligonucleotide technology from ValiGen N.V. (Rotterdam, the Netherlands). The technique, called chimeraplasty, uses the cell's DNA repair mechanisms to induce conversion of a specific base in the genome.
While the company sees chimeraplasty as a useful tool, it is not expected to have an impact on consumer opinions.
"We view this technology as a complement or adjunct to other tools we're