Like Frankenstein shambling over the countryside, genetically altered plants have escaped from the labs.

It has long been a fear in Europe that companies would not be able to prevent the spread of genetically modified crops, foods altered to enhance nutrition, grow larger, or last longer on store shelves. Consumer groups and scientists have warned that once such organisms get into the wild, they could present a danger not only to the ecological balance of nature but also to humans and animals who eat them.

Their fears may have been realized.

In a scene reminiscent of Jurassic Park, man-made, genetically modified (GM) plants have made their first large scale escape from the labs and been discovered growing wild in the U.S., scientists reported Friday. Can those Frankenfoods be far behind?

In field research conducted in North Dakota, the scientists found that genetically modified canola was spreading in the countryside and mingling with existing strains, creating "transgenic" strains of canola. The researchers said that the unintentional release of such GM plants could have serious implications.

"These observations have important implications for the ecology and management of native and weedy species, as well as for the management of biotech products in the U.S.," said one of the study's coauthors, Cynthia Sagers from the University of Arkansas.

The genetically modified traits imparted to the canola plants, for example, make them resistant to certain herbicides, which makes them hardier. But if such a characteristic were genetically passed on to another plant, an invasive weed for example, the results could be disastrous. It could make a destructive and invasive plant difficult to eradicate and help it spread out of control.

So how worried should you be?

Sager and her colleagues' discovery isn't the first instance of GMs escaping into the wild. Canada and Japan have already reported such jailbreaks, according to the Ecological Society of America. It is unknown what the effects will be on food -- if any -- although some people have reported allergic reactions to genetically modified plants.

Indeed, in other parts of the world genetically engineered byproducts -- so-called Frankenfoods -- have already unintentionally made it onto grocery store shelves.

In the U.K, the country's Food Standards Agency revealed recently that beef from the offspring of a cloned cow was sold to consumers last year. That beef was eaten by consumers. Furthermore, the FSA said that it has uncovered yet another case of cloned beef being sold to the public. It is also now investigating the possibility that milk from cloned animals was sold to families in Britain.

There was no identifying or warning label on any of these foods, said the FSA, and the agency says such foods are illegal because they must be first approved and tested for safety as "novel foods."

The European Parliament has voted for a ban on foods derived from clones and their offspring as well, but it has not become the law of the land there yet.

These recent developments have alarmed consumer advocates given how rapidly GMOs are spreading before they can be adequately tested and their effects on humans studied. It was just 14 years ago when the first mammal cloned from an adult cell, Dolly the sheep, was created.

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