Genetically modified foods at the Food Coop

Roux42:

Refreshingly informed post. Nice to know some folks are staying on top of this little discussed topic.

While the environmental and economic effects that Roux42 talks about are somewhat understandable, it's the effects on human health of GM foods that are most frightening and at the same time, most difficult to understand.

In my experience, people will tolerate a lot of environmental destruction before they take action. But try to poison them -- now that's serious.

To say the GM foods won't poison you is too easy. A lot of what we now accept as "normal" levels of cancer were unheard of 50 years ago. No one knows for sure why cancer rates are rising so quickly, instead we are all directed to focus on the "wonderful" cures that the drug companies have created. Unfortunately there is no money to be made in preventing cancer and a lot of money in treating it.

I think history will show that a lot of cancer is caused by the toxic chemicals in our environment, all of these of course brought to us by the same folks who are selling the cancer "cures".

Interesting, no?

Carnivore wrote: [quote=greg]As it turns out, many/most folks had very little information on the topic.

Now, I don't know what Drano does when he's not cleaning our clogged drains, but I suspect he probably has a profession.

Which means he knowsa lot about whatever it is he does.

So if he heard some folks talkiing about whatever it is in the most uninformed or superficial manner, he would probably be compelled to set the record straight.

That's basically what happened here with me.

Greg, I've met you, and I was under the impression that your profession was real estate. I don't really see how that makes you more qualified than Drano to have an opinion on this subject. Reading a few books that were carefully selected to support your pre-existing point of view and going to a few meetings do not make you an expert. And they certainly don't give you a right to pontificate about how uninformed everyone else is. So far in this thread (and the duplicate thread on the Park Slope board), your arguments have been some of the least cogent and the least based in fact of any presented. Jack Krohn asked you for a reference supporting some of your statements, some study perhaps that supported your point of view, and all you did was repeatedly give the same link to a website that itself lacked any scientific credibility. In fact, roux has given a much more reasonable argument supporting some of your position than you have.

You're entitled to your beliefs, but not to belittle everyone who doesn't happen to agree with you. You've spoken about how little information everyone has on the topic, but you've given opinions, not information. If you want to "set the record straight" you have to do it with facts, not opinions. The difference between Noam Chomsky and the sources you've cited is that Chomsky meticulously documents the evidence that underlies his point of view.

I've been studing this topic (GM foods) since it attracted my attention in the late 80's. I have not "read a few books" or "heard a few lectures" but rather have followed the topic closely the in mainstream media for all of that time. And thought about it all of that time.

Reading and thinking about GM food for 15 years can get you pretty far into the topic.

As far as my current means of livelihood, it's just that. It hardly defines me or my interests. I've had a number of careers, including being a pre-med undergrad, market researcher for a food company and computer magazine, taxi driver, non-profit housing developer, etc.

As for my arguments about GM food, I simply find it preferable to cite a resource that covers all of the information at hand. It would be very boring to recite here on this list when it already exists elsewhere in a lot more detail than I have time to replicate.

Now if you want to talk about the specific items on Jeff Smith's website, please go there and let's hear your refutation. Just dismissing them all as undocumented is hardly fair to Jeff or the readers of this message.

Carnivore wrote: [quote=greg]As far as my current means of livelihood, it's just that. It hardly defines me or my interests.

You were the one who tried to dismiss Drano's point by saying this:

greg wrote: I suspect he probably has a profession. Which means he knowsa lot about whatever it is he does. So if he heard some folks talkiing about whatever it is in the most uninformed or superficial manner, he would probably be compelled to set the record straight. That's basically what happened here with me.

By saying that, you implied that you were speaking about GM foods as a professional, which was false.

greg wrote: Now if you want to talk about the specific items on Jeff Smith's website, please go there and let's hear your refutation. Just dismissing them all as undocumented is hardly fair to Jeff or the readers of this message.

He has to actually cite the study before I can read it and refute it. He never does that. And for the record, unlike you, I don't have a vested interest in either side of this argument and am open to an honest debate. But honest debates begin with facts, and since Smith's website doesn't actually cite any facts (only references to his own book) there is nothing to "refute."

What I'm suggesting here is that Drano and yourself and certainly everyone on this list has something they do either as a vocation or avocation. While my vocation is currently being a real estate broker, I'm also a member of the Environmental Committee at the Food Coop. In that capacity, I've spent a lot of time reading and thinking about the topic of safe foods. I've certainly spent more time and effort delving into the topic than most readers of this list. Whether or not this qualifies me as a "professional" seems rather moot and I'm not sure what that means in any case.

As to Smith's lack of scientific basis for his observation, I can't believe you've bothered to look at his site, for there are references galore.

Just to make my point, pasted below is a typical citation from the site:

GM Food Promoter Transfers to Rat Cells

The cauliflower mosaic virus (CaMV) promoter was found intact in rat tissues after a single meal, and was also confirmed to be active in human cells.

The full 1100 base pairs of the CaMV promoter was found:

In stomach cells and in intestinal (mesenteric) lymph nodes two hours after eating;
In mesenteric lymph nodes, kidney, and liver cells six hours after eating; and
In mesenteric lymph nodes, spleen, and liver cells three full days after eating.
Future tests will determine if the CaMV is active.

Seven groups of six rats each were intragastrically intubated (fed through a tube to the stomach) with a balanced diet. Added to the a small portion of the diet was a single dose of a genetic construct similar to those used to create genetically engineered crops. This construct included a gene that codes for a green fluorescent protein. The negative control group had no promoter attached to the green fluorescent protein gene at all; the positive control used human cytomegalovirus promoter known to be active in all mammalian cells. The test group had the CaMV 35S promoter coupled to the gene. The design tested the DNA construct in both circular and linear form. A final control was not fed any DNA at all. About half of the CaMV fed rats in each of the circular and linear DNA groups were found to contain intact CaMV.

Tissue samples remaining to be tested will soon determine if the CaMV is active, causing the expression of the green fluorescent protein.

In a separate but related study, the same three constructs described above were added directly to human intestinal epithelial cells (both small and large intestines), rat cells, and fish cells, in vitro. The fluorescent gene was expressed in all the cells tested.

Implications for human health

The CaMV promoter is attached to inserted foreign genes in nearly all genetically engineered foods. It overpowers the cells’ own self-regulatory mechanisms so as to permanently turn on the foreign inserted gene and produce large amounts of the transgene proteins. Without the promoter, the gene would likely be dormant in the DNA, unexpressed. Scientists use the CaMV because it is aggressive and because it works in the DNA of all types of plants.

The assumptions used by biotech advocates as the basis of safety claims were that the CaMV:

Is stable
Will only turn on the gene to which it was attached
Is plant specific and will not function in mammals, including humans, and
Will not transfer from food to gut bacteria or internal organs;
Each of these assumptions have been contradicted.

1. Studies also show that the promoter creates a "hotspot" in the DNA. This means that the whole chromosome can become unstable. This may cause breaks in the strand or exchanges of genes with other chromosomes. Research reported in June 2003 confirmed that genetically engineered crops exhibited broken DNA sections at the CaMV.

2. The CaMV promoter may turn on native genes over long distances up and down the strand of DNA. It can even turn genes on in a different chromosome. This can create a flood of proteins that may create toxins, allergens, carcinogens, or nutritional changes.

Some scientists believe that the CaMV promoter, in conjunction with other genetic material, might also create a growth factor that could result in excessive cell growth - a potentially pre-cancerous condition. A study by Ewen and Pusztai demonstrated significant cell growth in the stomach and intestines of rats fed a genetically engineered potato. An Egyptian study also showed evidence of cell growth in rats fed a Bt potato, and a feeding study on genetically modified peas showed greater weights of rat intestines, supporting the possibility of extra cell growth.

While scientists believed that the aggressive nature of the CaMV promoter might have been responsible for these results, it was not confirmed whether the CaMV promoter was able to transfer intact to organs and whether it would be active in human cells.

The new evidence confirms the transfer and potential activity. The new evidence does not, however, show any specific links to cell growth, nor does it confirm that unstable hotspots or the turning on of dangerous genes will occur in mammalian DNA.

Bored yet? Want more?

There is a lot more at:

http://www.responsibletechnology.org/GMFree/AboutGMFoods/DangersofGMFoods/index.cfm

Carnivore wrote: I admit that I didn't follow all the links on the site after reading the pseudo-science on the front page and the fake references.

As far as the above study goes, it's exactly why I wanted to see specifics. This is a perfect example of an attempt to mislead people through bad science. The rats in the study were fed not a food derived from a GM crop but the genetic construct used to make those crops (presumably plasmids or a virus vector). Of course those constructs did what they're supposed to do: insert genetic material. Those genetic constructs are not what people eat when they eat foods derived from GM crops. To infer from this that the crops themselves are unsafe is a leap that is not based in reality.
An analogy: hominy grits are made by treating dried corn with lye. The study above is like feeding a bunch of rats some lye, observing the tissue damage, and then saying: "see, hominy grits are dangerous!"

The study wasn't designed to show anything meaningful about the effects of consuming GM crops, but is cited as though it does.

A professional would have recognized that immediately.

Comparing cauliflower mosaic virus (CaMV)to lye is like comparing gunpowder to a tactical nuke. Lye was probably used by native Americans to prepare hominy for thousands of year before Europeans arrived on the continent Cauliflower mosiac virus? Do you really want to know?

More importantly however, the analolgy is not correct. It appears that the CaMV travels with the GM plant and is integrated into the genome.

So what we have here is a case of the chef leaving the lye in the hominy. In the case of the hominy, the diner would reject it immediately. In the case of CaMV, our test buds have not evolved yet to detect this exotic ingredient. Or maybe they do, as the study below by Prof. Joe Cummins suggests.


Eating Cauliflower Mosaic Virus infected vegetables does not prove that that Cauliflower Mosaic Virus Promoter in genetically modified crops is safe
Prof. Joe Cummins

Recently researchers from the John Innes Centre (JIC) for plant research in Great Britain have again claimed that the Cauliflower Mosaic Virus (CaMV) promoter used to genetically modify virtually all of the transgenic crops now marketed or being tested for marketing has been proven to be safe for human consumption because humans have been consuming virus infected crucifers for a long time. It is worth pointing out that virus infected crucifers are not tasty items and they are avoided by most animal predators including humans. JIC may be exceptional in consuming large quantities of virus infected crops and certainly those laboring at the institute are worthy of fuller study. Even if virus infected crucifers could be prepared and consumed as dietary treats the fact is that the behavior and potential hazard of the CaMV promoter in transgenic crops is unrelated to the replication and behavior of the virus in the plant cell. It is simply unreasonable to maintain that the the integrated CaMV promoter in transgenic crops behaves the same way in the virus replication cycle as it does in the chromosome of the transgenic crop.

CaMV is a pararetrovirus which means that it transmitted as a double stranded DNA virus that replicates using reverse transcription of RNA into DNA. The replication of CaMV is similar to the replication of a related pararetrovirus Hepatitis B (Seeger and Mason 2000). In CaMV replication the infecting virus enters the plant cell then transfers a copy of the viral DNA to the plant cell nucleus where it forms a nuclear plasmid that very rarely (possibly never) integrates into the chromosome. The viral DNA is transcribed releasing both messenger RNA for making virus components and RNA copies of the viral chromosome that are translocated to the cytoplasm where the RNA copies of the viral chromosome are packaged in virion like particles. Within the virion like particles the RNA is reverse transcribed to make the viral DNA that is released from the plant cell in the mature virus (reviewed in Poogin et al 1998).

When CaMV genes are inserted into the DNA of the plant chromosome those genes may recombine with infecting CaMV virus. Wintermantel and Schoelz (1996) found that recombination was observable in every plant when virus invaded transgenic plants with CaMV genes inserted on plant chromosome. They believed that most observed recombination occurred in the cytoplasm during reverse transcription and that there was little chance for recombination between invading virus and CaMV transgenes on the chromosome. Genes such as human interferon have been inserted in CaMV virus and were found to produce interferon in virion like particles but the human genes were not reported to have recombined with plant chromosomesDeZoeten et al (1989).Plant gene replacement vectors based on CaMV have been discussed for nearly twenty years but have not proven highly useful because the only small DNA inserts have proven feasible but recently Viapana et al (2001) have experienced improved success by employing helper virus.

Earlier we discussed the problems with CaMV promoter integrated into the chromosome in great detail." We pointed out that the CaMV 35S promoter is promiscuous in function, and works efficiently in all plants, as well as green algae, yeast and E. coli. It has a modular structure, with parts common to, and interchangeable with promoters of other plant and animal viruses. It also has a recombination hotspot, flanked by multiple motifs involved in recombination, and is similar to other recombination hotspots including the borders of the Agrobacterium T DNA vector most frequently used in making transgenic plants"(Cummins et al 2000).

In conclusion , authorities from JIC base their belief in the safety of CaMV promoter in transgenic crops on their belief that people and animals massively consume virus infected crops without apparent discomfort. The natural history of CaMV replication in plants clearly shows that the CaMV promoter installed in crop chromosomal DNA is entirely different from CaMV virus replication so that the presumed safety of eating CaMV in crops has no real bearing on the safety of genetically engineered crops with CaMV promoter. In fact JIC seems to be suffering from "tunnel vision" and directing research away from the real problems with crop genetic technology. The JIC argument surely impresses science administrators and government bureaucrats who, unfortunately, control research funding and gullible journalists who influence public opinion. Even though the discussion between us and JIC has grown repetitious ultimately the inappropriateness of the JIC pronouncements will be widely recognized and then progress can be made in judging the safety of transgenic crops with CaMV promoter.

References
Cummins,J,Ho,M and Ryan,A "Hazardous CaMV promoter?"2000 Nature Biotechnology 18, 363 DeZoeten,G,Penswick,J,Horisberger,M,Ahl,P,Schultze,P and Hohn,T "The expression,localization and effect of human interferon in plants" 1989 Virology 172,213-22
Poogin,M,Hohn,T and Futterer,J "Forced evolution reveals the importance of short open reading frame A and secondary structure in the cauliflower mosaic virus 35S RNA leader" 1998 J. Virology 72,4157-69
Seeger,C and Mason,W " Hepatitis B Virus Biology" 2000 Microbiology and Molecular Biology Reviews 64,51-68
Viaplana,R,Turner,D andCovey,S "Transient expression of a GUS reporter gene from cauliflower mosaic virus replacement vectors in the presence and absence of helper virus" 2001 J Gen Virol 82,59-65
Wintermantel,W and Schoetz,J "Isolation of recombinant viruses between cauliflower mosaic virus and a viral gene in transgenic plants under conditions of moderate selection pressure" 1996 Virology 223,156-64