Sunday, June 24, 2012

What is "Genetically Modified"? and the Frankenfood Pardox

The misreporting of "GM grass killing cows with cyanide gas" has stirred quite a discussion!  People are now realizing that hybrids are tremendous random mixing of genes, most with no known function, in ways that can create dangerous outcomes!

But its natural!!

Now many on comment threads are calling for outright bans on hybrids, as they are not natural and humans had to make them. But wait, these aren't the Frankenfoods that they usually make up false information about!  What are these curious "hybrids"?

Jennifer Mo @noteasy2begreen asked for a concise reference for what Genetic Modification really means. To me, it means, well, modifying genetics.  It is when something is added to the genome, that is DNA added (or deleted or changed) in a cell's genetic material.

This is not the definition used in popular discussions.  Genetic Modification in the common vernacular means a gene (or genes, usually a couple) that are added to an organism to confer a valued trait.  This requires a lab and recombinant DNA technology.

But this is what I call the Frankenfood Paradox.  Transgenic modification in the lab is the least invasive genetically, it is the most well understood, yet it is the one most shunned by those that oppose biotech.

Here is a table that might help.  Click to enlarge.

Here are the ways that plants are genetically altered.  Note that all of them are acceptable to most people, despite having no idea what the heck is being changed, and the huge number of genes affected. 

Here is the paradox!  What you will find is that transgenic technologies are much more understood, predictable, traceable and safe.  Fewer genes are moved and we know what the genes do. We can determine where genes land in the genome and where/if/when/how much they are expressed. However, these  are not allowed in organic cultivation and people want to label them. The acceptable methods move or alter tons more genes in random ways that can't be traced or even remotely understood.

I threw this together in a moment's notice, so please offer some comments!!! Let's keep it accurate as can be (e.g. I can't think of any documented adversity on a polyploid or mutation breeding line).


Mary said...

Yeah, you can get nice and precise alterations with GMOs.

But then they move the discussion and say "well, ok, Bt reduces pesticide...but other pests still exist..." I call that the "you're not killing enough" argument.

You can't win--goalposts move every time.

Cameron said...

I'll give you "more understood" and probably "more traceable". I don't think you can claim "more predictable" or "more safe" without some data to back it up.

However, my main issue about GMO is the non-beneficial changes being made to DNA to make it more profitable. For example: deliberately sterile plants, plants that won't grow without enablers. This is a waste of time.

Kevin M. Folta said...

Hi Cameron. Deliberately sterile plants (and animals) have been traditionally bred for centuries with no complaint. There are no transgenic plants that are, or ever have been, grown to be sterile. That technology was from Delta Pine and was never deployed.

Non-beneficial changes? I think you'd find quite a number of farmers that would argue with that. They still can buy non-GM hybrids. Many choose transgenic because it works for them. Saves money, fuel, time, labor. More profitable, sure, but farmers deserve to profit now and then too. Thanks for your thoughts.

Hotshot said...

Depends on what you mean by adversity, but both polyploidy and mutations can result in sterility, which can be good or bad, depending on how the plant is cultured. Mutations can cause chlorophyll deficiencies, which can be good or bad, depending on use. It may be good for non-food horticultural crops. It is possible for mutations to result in protein deficiencies or different lipid profiles, which again depends on the use.

Hotshot said...

Cameron, there are also no crops being produced using transgenics that require enablers. Roundup ready just means that you CAN use Roundup on the crop to control weeds. If there are no weeds present, you don't have to use Roundup, and your crop will yield just as much as it would have with Roundup. Roundup ready is just a management tool for farmers that makes weed control less complicated, because Roundup is a chemical that is relatively safe for the user and the environment.

Jennifer @noteasy2begreen said...

Nice chart, Kevin! From the comments on various articles on the hybrid grass incident, I'm seeing that many people are unclear about the difference between hybrid and transgenic. I'd love to see your chart with clear, appealing, public-friendly illustrations. I think that would be palatable to people who wouldn't seek out the info on their own. Too much to ask?

Kevin M. Folta said...

Jennifer, not at all. I'm working on an article for a popular magazine. It will be part of it. Maybe I can use your help in making sure it is effective. I'll keep you posted on this. Take care.

Gordon Wells said...
This comment has been removed by the author.
Gordon Wells said...

Wouldn't longitudinal whole genome sequencing allow for some of those "Nos" to become "Yes"?

Kevin M. Folta said...

Gordon, in some cases yes, at least to inventory the variation arising from a cross. The problem is that hybrids, by definition, will be highly heterozygous in most cases and whole genome sequencing (WGS) would have difficulty resolving genotypic differnces.

Perhaps if there was a good reference genome some WGS could be aligned to show these differences. I think it would work great for mutation breeding if you had the non-mutagenized wild type.

I don't think there is any chance of WGS on polyploids any time soon, except maybe for some recent autopolyploids. With short-read WGS in a repetitive genome, you have no idea which contigs match with contigs from homoeologous subgenomes.

The big problem of course is that once you find the differences, you still rarely know how those differences affect the traits of interest. Remember, out of the average 40,000 genes in a plant, the function of only about 10,000 have been experimentally shown.

Bottom line, precision is in transgenic approaches. The rest is an educated guess. Any plant breeder will be proud to tell you that it is just as much art as science.

Excellent point.

Ewan R said...

Kevin - on the table you have time for a new variety of GMO @ less than 5 years - are you interested primarily in simple traits here while also ignoring the regulatory approvals process? Or are we talking about jumping an established transgene around between varieties?

In the first case generally you're looking at 5-10 years to commercialization (longer the more complex the trait is, particularly in just developing it), in the second case you can probably introgress, with an aggressive breeding program, in way less than 5 years. Of coruse with a simple trait you could probably have a working plant in a far shorter timespan - but this isn't really pertinent with today's regulatory environment.

Kevin M. Folta said...

Ewan, yes, the table refers to the science- the potential to install and trial the trait of interest. The number comes from the cisgenic apple people that describe 50+ years to install apple scab resistance vs. <5 years to do it with the cis-gene.

The regulatory issue is a separate one, and maybe the table needs an asterisk there. Certainly we've seen how long that process can take, especially for a public program (like Ralph Scorza's PPV resistant plums) that does not have the in-house legal expertise and $$ to navigate the process.

Gail Gardner said...

A person's position on GMO can often have a lot to do with whether they are thinking short or long term. Scientists are making far too many assumptions and seem to totally ignore the potential for unintended consequences. There is no way to know the long term effects of genetic manipulation on human health because all the variables could not possibly be controlled for in ANY study. That something does not kill you immediately doe NOT make it safe to consume. No doubt you could consume trace amounts of arsenic for a long time but eventually doing so WILL kill you.

I would also like to hear how scientists can be sure that terminator genes will not jump species and end up sterilizing ever more plants.

While those who are pro-GMO seem totally unconcerned, it is quite possible that GMO crops could end up cross-contaminating and eventually eliminating heirloom crops. I for one do not believe that if that were to happen science is going to be able to reverse what they have done.

I will stand up for your right to eat whatever you wish, but I demand my right to AVOID EATING whatever man creates for any reason I so choose.

Gail Gardner said...

Genetic Engineers Explain Why GE Food is Dangerous

Kevin M. Folta said...

Gail, First, we do know long term consequences. Not only have they been studied, we also understand the potential ways that a gene or protein can be problematic.

What about the EPSPS gene concerns you? What makes it different from the natural copy that would make it dangerous?

What is it about Bt, an protein toxic to insects and used in organic cultivation? If long-term studies have not been done, how can organic produce be safe?

I'm not being confrontational, I'd really like to know your thoughts on these questions. I can assure you that there is no problem and none likely to ever occur. Science says so.

And that link to the "Genetic Engineers" article... I can debunk anything in that brochure. They even quote me in there! Tell me what you think is the #1 most compelling piece of evidence and I'll explain to you why it is not worth worrying about.

Thanks for your thoughts.

Kevin M. Folta said...

I do disagree that is is a short-term/long-term issue. It is whether you accept science or deny science. The anti-GMO movement is laughable to scientists, except for a few that profit from it. The science denial of the anti-GMO position is the same as the science denial of the anti-climate change folks. They accept crappy data and lousy science from people they trust, and ignore the voices of independent scientists. It is weird. We have facts, but people are so entrenched in anti-GMO anti- climate change that they can't see, or want to understand, real science. It is the ultimate crying wolf.

I'd be glad to help you if you are interested.

Toss me your best argument from that report. I read it all, nothing new, same old stuff.

Kevin M. Folta said...

One last thought Gail. What "heirloom crops" do you worry about with GMO contamination?

Do you worry about heirloom crops hybridizing with other pollen from non-GMOs that would make them no longer heirlooms? What steps are you taking to ensure that is not allowed?

Think about these questions. Your fears are without foundation.

Kevin M. Folta said...

Gail- I'm sorry, I missed this one. You asked a few questions, if I didn't get them all contact me, okay?

"I would also like to hear how scientists can be sure that terminator genes will not jump species and end up sterilizing ever more plants."

Easy. No such technology was ever deployed. The technology to produce sterile cotton bolls was developed by Delta & Pine. They used it in cotton and tobacco, only in greenhouses.

They were bought out by Monsanto in 2006 or so, and Monsanto never used the technology.

Of course, anti-GM folks believe that this is commonly used and the end of agriculture. However, there is no possibility, at least unless nature comes up with its own... which it did! A subject for another blog.

Even if it was deployed, the idea of it "jumping species" is a little far fetched. How many genes do you think move from species to species in plants? Not too many, unless species are closely related.

Most importantly, if it did "jump species" the plant would not produce seeds, so that plant, and that gene, are at a dead end and can't move into a population.


Mike Lewinski said...

First, I really appreciate the table you provide in this article and plan to refer to it in the future.

Second, I've been coming around on the GMO issue after a long time (since 1990 when I first started learning about it). The comments here are interesting. I don't worry about "terminator" genes because of the very last reason in the comment above. There's no benefit to them in the wild, only detriment.

I feel some sympathy with this guy:

I wouldn't go so far still as he does to say I was completely wrong about GMOs. I think they are being used first and foremost to prop up monocultures that are inherently unsustainable. None of the current products I know about that are being sold here in the U.S. are inherently better for humans or farmers or the environment in the long run (and I'll give you profit for the farmers in the short run).

Even setting aside the massive non-renewable petrochemicals used in fertilizer, pesticides and fuel, monocultures strike me as the ecological equivalent of the vacuum, "abhorred by nature". Eventually a crack in the seal will let evolution in. It would be smarter to not have all our eggs in a single basket, accepting some losses in productivity in exchange for resiliency (one complex systems theory says sustainability is found in a balance between efficiency and resiliency of a system's energy flows - too efficient creates single points of failure - the blight that ruins the whole wheat crop for example, while too resilient can't scale to meet the system's needs and creates stagnation--or starvation in the case of humans).

From the flip side, it's clear we won't be able to perpetually contain any GMO organisms we create. On first blush the idea of transgenic salmon escaping hatcheries seems absurd, but I can imagine any number of ways it might actually happen given sufficient time .

I believe that some things are predictable, or should be, but that unintended consequences are inescapable. I'd have to condemn all technology if I wanted to be consistent in preventing them, and I don't want that nor do I want to ban GMO as a technique.

In the case of the transgenic salmon that grows at twice the rate of wild salmon: does that increased growth provide a benefit for spawning? If so I can see it leading to propagation of the gene if it "escapes" (and I know it's already there in the wild fish it was taken from). It would only perpetuate itself if the wild salmon gain some benefit. It's hard to imagine it seriously hurting wild salmon populations if the gene doesn't confer a reproductive or survival advantage, since it would have no reason to spread.

But I can imagine other unintended consequences of the gene helping the wild salmon enough that it also changes their migratory timing and affects other wildlife. So even if the gene were a net positive for the wild salmon growing faster (with the bonus of now also dodging predators timed to the wrong cycle) I can see it being an ecological net minus for the rest of the food chain.

On the other hand, I look at the other ways gene transfer can happen and wonder why the wild salmon don't already have the gene via retrovirus? Maybe it's no good in the wild in that species in that way for the reason that you have to spawn at the same time with the rest of your kind and growing fast early doesn't let you do that.

So I think the salmon are a case where 1) the risk of escape is much lower than in plants whose pollen may blow on the wind and 2) the gene in question is already "in the wild" albeit not in wild salmon and come to the conclusion that it is a low risk, high gain proposition. Some day the gene will get "out" and possibly there'll be some ecological disruption if it does confer advantage and spread...