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Suppressed Report Shows Cancer Link to GM Potatoes
Doc Ruby writes "After an 8-year-long court battle, Welsh activists have finally been allowed to released a Russian study showing an increased cancer risk linked to eating genetically modified potatoes. While the victory of the Welsh Greenpeace members in the courtroom would seem to vindicate the work of the Russian scientists that did the original research, there are still serious questions to be answered. The trials involved rats being fed several types of potatoes as feed. The rats who were fed GM potatoes suffered much more extensive damage to their organs than with any other type; just the same, serious questions remain about the validity of the findings. The Welsh group wants to use this information to stop the testing of GM crops in the UK, tests currently slated for the spring of this year."
The paper being described in TFA can be found Here. Also, there are almost a dozen different citations of the paper on Google Scholar
"And _do not_ give me that old "it'll help starving people" crap."
Most of the GM foods being pushed have nothing to do with starving people - it's all about increasing corporate profits, as usual. The "terminator gene" was being pushed to prevent poor third-world farmers from saving their own seed after buying grain crops once. Roundup-ready crops are developed to allow farmers to use increasing amounts of Glyphosate to control weeds, because of the inherent problems with how large-scale agriculture is "managed". Flavr-Savr tomatoes were designed to be picked at an even less ripe state so they survive shipping better. All of that runs counter to helping starving people - heck, even for the "first world" it means crops that are less nutritious than before.
The only GM crop I know of that was developed in an attempt to actually help the third world is golden rice - a rice that provides beta carotine. That was developed at a university, and while given lip service by the agro-giants it's not high on their agenda.
#DeleteChrome
What we have a hard time accepting is that 99.5% similarity means jack, when we have something like 90% DNA similarity with sunflowers.
.5% different from rats, that means that .5% represents a hell of a lot of difference, not the other way around.
Wrong. You can't compare humans/animals and plants in terms of DNA similarity (or lack thereof). The basic structure is too different to make any comparisons worthwhile.
If we are only
Wrong. Most of the 0.5% difference between mice and humans involves genes that are currently classified as inactive. Thus they basically have no identifiable effect, even after decades of study. The amount of DNA that actually causes the differences between humans and mice is remarkably small. While 0.5% of the total DNA is different, approximately 98.5% of that 0.5% is considered inactive.
And like I said in my earlier post, decades of studies have shown that mice are a very accurate representation of humans, when it comes to testing chemicals. The organs are proportioned almost exactly the same, and comparable responses to humans have been observed again and again and again. Doubt it if you wish. The fact remains that if something is harmful to mice, we can be sure that a relative proportion of that chemical is harmful to humans.
That's the right question, left neglected and alone by the story.
Poking around a bit, it turns out that the genetic engineers and the researchers were both looking at one particular lectin, introduced to make the potatoes resist insects and nematodes better. Which is important because "lectin" is a whole family of chemicals with different biological effects.
Now, the natural chemical defenses in plants are bad enough. Wild potatoes may need elaborate preparation to be safe to eat. Farmed ones are screened for solanine. Potatoes, in case you didn't know, are in the nightshade family.
So the real question here is what other research was done and what results it had. Does other work confirm or contradict the Russian study?
Then there's the systems question, which is whether we're better off with the risks of the engineered potatoes or the risks of the pesticides needed to keep "natural" ones alive. The word "natural" is in quotes because they're quite different from their wild relatives.
Uhm, why are you guys pulling these ridiculous percentages out of thin air? They are woefully incorrect. Ever heard of the various gnome projects that have completely sequenced the dna of certain animals and plants? There is still a large margin of error based on the precise definition of "similarity", but based on the genome projects that have sequenced a human and a rat, the number was much closer to 80% for rats. And the estimates were around 40% similarity to humans for chickens(gallus domesticus). Our common ancestor with rodents was around 85 Million years ago, and we've diverged quite a bit more than .5% since then. Heck, just look at the number of chromosomes of rats and humans, humans have 3 more haploid chromosomes, that's around a 13% difference alone, so obviously the 99.5% number is completely bogus. erm, well he said mice, but mice and rats are pretty close, and both used for lab experiments. ah, here is a pretty picture that shows structural differences within the chromosomes as well: http://en.wikipedia.org/wiki/Chimpanzee_Genome_Pro ject
It's rare to find so much misinformation at Slashdot, and that's saying something.
Humans and chimpanzee DNA are very similar, there are apparently about 40 million differences (out of about 3 billion positions) between chimp and human DNA; in protein coding regions, the number of differences is much smaller.
Humans and mice, on the other hand are far more evolutionarily distant (80 million years since the last common ancestor, compared with 5 million, or less for chimps). In protein coding regions, mouse and human DNA sequences are about 80% identical, on average, but outside protein coding regions, the level of sequence similarity is no higher than would be expected by chance. (This large difference was one of the reasons the mouse genome was sequenced after the human genome - sequences that were more similar than chance were expected to have a function.)
While plants and animals (and bacteria) share a large number of proteins that do similar things, their DNA sequences do not share any significant similarity except in protein coding regions for very highly conserved proteins.
What all of this has to do with unpublished Russian studies on genetically modified plants, I cannot imagine.