Could Bioengineered Organisms Spread "Genetic Pollution" After Being Released into Nature?

[xchrom]

http://www.scientificamerican.com/article.cfm?id=genetic-pollution

Dear EarthTalk: What is “genetic pollution” as it pertains to the bioengineering of animals, fish and plants, and what happens if they cross breed with their wild cousins?—R. Ahearn, Rome, N.Y.

Genetically modified organisms are those that have been altered by scientists to include genes from other organisms (known as transgenes) that may impart specific benefits. For instance, crop seeds that have added genes which resist the effects of herbicides can allow farmers to spray their fields liberally with herbicides to kill undesired weeds without the fear of killing their marketable crop along with them.

Genetic pollution is the release into the natural environment of these altered genes, creating the risk that they might breed with wild plants or animals and spread out uncontrollably. Reports author Jeremy Rifkin in his landmark 1998 book, The Biotech Century: “Some of those releases…could wreak havoc with the planet’s biosphere, spreading destabilizing and even deadly genetic pollution across the world.”

To follow through on the previous crop seed example: If herbicide-resistant, genetically engineered crops were to breed with their wild cousins, it could lead to the creation of super-weeds undeterred by control efforts. The weeds could, in turn, edge out native species and drive them to extinction, causing an overall loss of genetic diversity. According to Greenpeace, crop genetic diversity is “essential for global food security” and a lack of it can be linked to many of the major crop epidemics in human history, including the Southern corn leaf blight in the U.S. in 1970. They quote noted botanist Jack Harlan who said that genetic diversity is all that “stands between us and catastrophic starvation on a scale we can not imagine.”

[dipsydoodle]

1. That has always been the main fear

Cross contamination.

[pscot]

2. Is this problem for nature

or for us? If we aren't dumping chemicals into the environment, these modifications will have no selective value. And I have a feeling our chemical interventions are going to end soon..

[phantom power]

3. I've always felt like nature will treat it as just one more source of genetic innovation...

of which there are already many. Like you say, how it may impact us in particular is another story, since we're the ones who are trying to benefit from controlling what organisms express what genes.

Another issue is that different categories of organism have very different rates of 'gene sharing'. Bacteria appear to share genetic material at will. Plants can share, but not with the same ease as bacteria. I don't know what the rate of cross-species sharing is for animals, but I'd bet a donut it's a lot less than for plants.

[xchrom]

5. It's one thing for earth to be indifferent.

It's another for us to be indifferent to what ever pollution we dump.

[pscot]

6. I'm not indifferent

But the long term impact of these genetic mods is probably less than we think. Certainly not on a par with burning carbon.

[xchrom]

7. 2 things. Science on genetic pollution isn't clear.

Not man made genetic pollution - right there - that indicates a kind of bad science.

2- our problems get magnified now by each blow to the environment.
Weaken natures genetic ability to deal with rising seas - etc.

Technology as an answer can't be given a religious pass.

Technology - when it comes to the environment - presents problems for us.

[NickB79]

4. Could Holsteins released into the wild wreak havoc with the ecosystem?

Probably not. Without human assistance, they'd quickly die off in competition with native species due to being so heavily domesticated over the millennia. Most of our GM crops are similar; their traits are only a selective advantage when humans are the ones doing the selecting, not nature itself. If a crop confers herbicide resistance to a wild relative, what selective pressure will allow that trait to spread in a forest or prairie where herbicide isn't sprayed regularly?

The article seems to be confusing genetic diversity of wild, free-ranging plants with genetic diversity found within already domesticated landrace crops.

[pscot]

8. Absolutely

The wolves would laugh themselves to death if the cholesterol didn't kill 'em.

[Odin2005]

9. I was goinjg to post the same thing.