Biologist Rick Howard and his colleagues have discovered a paradox that crops up when new genes are deliberately inserted into a fish's chromosomes to make the animal grow larger. While the genetically modified fish will be bigger and have more success at attracting mates, they may also produce offspring that are less likely to survive to adulthood. If this occurs, as generations pass, a population could dwindle in size and, potentially, disappear entirely.
"Ours is the first demonstration that a genetically modified organism has a reproductive advantage over its natural counterpart," said Howard, a professor of biological sciences in Purdue's School of Science. "Though altering animals' genes can be good for humans in the short run, it may prove catastrophic for nature in the long run if not done with care. And we don't know just what kind of care is necessary yet, or how much."
This research, which Howard conducted with William Muir of the animal sciences department and Andrew DeWoody of the forestry and natural resources department, appears in this week's (Feb. 17) online issue of the journal Proceedings of the National Academy of Sciences. Howard and Muir published a related article in the same journal in December 1999 that showed larger animals had a mating advantage, but their previous article did not relate mating advantage to genetic modification (see below URL for related news release).
The most common question posed about genetically modified organisms - GMOs for short, and also called transgenics - is whether they are safe for people to eat. When GMOs were first made commercially available in 1996, many food crops, such as corn and soybeans, were altered to produce substantially more yield than they do in nature. The debate on GMOs
Contact: Chad Boutin