Sunday, January 20, 2008

Clonal Discrimination

Today the lay public is very concerned that they are eating the meat of cloned animals. When I first learned this I had trouble understanding why, as this seems like such a non-issue (for numerous reasons). Naturally, I figured the media was somehow to blame for the confusion, and a quick surf over at google news confirmed my suspicions. Turns out the FDA has, not surprisingly, approved cloned animals for human consumption. Basically a non-story. Until you enter the doomsday prophecies and start playing on people's fears of unknown new words and technologies. As I said, I think this is a non-issue, but I'm interesting in knowing why people think they should be worried about cloned meat. Here's what Reuters asks readers on their website:

"Would you consider serving cloned meat at your dinner table?"

And here are some responses that echo similar things I have heard from people in real life:

"No, we already do too many experimental things like rBGH and antibiotics."
That's right. I don't care if you've got gangrene or whatever, just stay away from those untested "experimental" antibiotics. Who knows what they might do.

"I’d never eat Cloned Meats, or genetically engineered fruits and vegetable. It’s not a natural creation. Seems to me that mankind has not totally destroyed all of nature yet for us to result to eating scientifically generated food."

Yeah I'm sure you only eat the products of "natural creation". Like coca cola, refined sugar or enriched flour? Or "scientifically generated" fermentation products like yogurt and beer? Unless you're living in the garden of Eden, there's no chance your living off "natural creations" dude. And what makes something so "unnatural" just because human knowledge is involved? Is knowledge "unnatural" too?

And on and on. Basically a lot of people think they should be scared of cloned meat, but it's pretty obvious from the commentary that none actually know what a cloned animal is. What exactly are they afraid to ingest? The cattle's aberrant histone modification patterns? At any rate, the question is irrelevant. It's just a programmed instinct to fear the unknown. The compulsion seems particularly strong when it comes to food. And hey, maybe that's a good thing - you wouldn't want people walking around randomly sampling concrete or poisonous mushrooms. And although I can't seem to think of any real reason cloned meat would be dangerous, maybe the infinitesimal risk is not merited if it doesn't offer any benefits. So the bottom line for me on cloned meat is this: no clear risk, no clear benefit. And so, for the time being, a total non-issue. Does anyone think I've missed out on something worth worrying about here?

Maybe it would be beneficial for us all if the media helped to spread some education while they are on the topic instead of promoting ignorance and knee-jerk fears?

UPDATE - Here's the marginally more informative article CBC ran.


Don said...

Natural v. cloned is a useless distinction to make if you are interested in safety. It sidetracks the discussion to one motivated by people's fear of what's new/strange to them. The concern should be a getting people fed safely and that's it.

kamel said...

So the bottom line for me on cloned meat is this: no clear risk, no clear benefit.

There was a good article about cloned meat in a recent issue of Wired ("The Other Other White Meat", November 2007). Anyhow, my sense of the 'cloned meat in the food chain' issue (which is echoed in the Reuters story you linked to) isn't that farmers want to clone animals for use for food per se, but rather use clones for breeding. As it stands now, cloning a cow is probably too expensive to make it worthwhile to do just to eat it, but if you have one, for example, that is a prodigious milk producer then it may make sense to clone it to keep that particular source of income going (or, selling 'copies' of that animal to other interested parties). So really, the benefit isn't necessarily to the end consumer but to farmers and breeders who can use cloning as a way to maintain desirable animals that you've already genetically engineered (for better milk production, growth rate, fecundity or whatever else) through traditional selective breeding.

Interestingly, the WIRED article suggests that cloned meat has been in the food supply since 2002 when the National Academy of Sciences released a report saying clone meat was safe to eat.

Like you, I'm left wondering what the rational arguments *against* cloned meat safety are.

The Doc said...

There are a few concerns regarding GE food.

Here is a good discussion about GE corn, and why it may not be as safe as it sounds:

The basic idea is that if you change the genetic composition, and the metabolic profile of the food (in the case of the GE corn above, you increase the amount of Lysine present), then you change the way the food behaves. In the case of the corn, you change the chemicals present after cooking - and there is evidence that this may increase cancer rates etc.

Anonymous Coward said...

It's not the actual genetic manipulation I'm concerned with but the privatization of food sources. Take GM crops for example, once you put in the roundup resistance and a terminator gene, you're forced to buy new seeds every year, and only one herbicide can truly be contemplated. It's a risk to food security and a threat to subsistence farming in developing nations. How long before there is something similar to the terminator gene in GM animals? When only privately owned "banked" sperm can be used to inseminate those animals. Other than that, I don't see why cloned meat should be any different than the regular kind. especially when you take into account the low genetic diversity of North-American cattle.

kamel said...

There are a few concerns regarding GE food.

Maybe true, but that's a separate issue from cloned meat, right? At least that's my understanding of the cloned meat issue - it's not about genetic manipulation to express antifreeze genes or produce chocolate milk, we're just talking about making genetically identical copies. Am I wrong?

If I'm not, maybe that's why there's an public fear of food from cloned animals because they're confusing the genetically modified food issue (I don't have a problem with GM food either, but maybe I'm not aware of all the legitimate concerns) with the cloned food issue. Or are there other safety (or ethical?) concerns with cloning farm animals?

kamel said...

BTW, anybody interested in reading the Wired article on cloned meat mentioned in my first comment can find it here

The Doc said...

That may all be so, but until someone can definitively achieve cloning including all the epigenetic add-ons, I don't think it is as safe as some would claim.

Cloning is not currently a techinique I would trust.

That's not, of course, the reason why so many people don't like it...

Ronald said...

Try the our new Mc Clone, now with 60% more methylation...

Bayman said...

Very interesting comments...

Cloning is not currently a techinique I would trust.

Why not? Do you mean you wouldn't trust the meat to eat or you wouldn't trust cloning to produce healthy livestock? If the latter I'd agree, but I don't see why meat from a developmentally defective animal would be any more dangerous than the good old-fashioned Texas longhorn.

I have to agree with Kamel that I still don't see how meat from a cloned animal is any different from one that isn't cloned. That said, you guys have raised important issues that will most likely arise when/if cloning comes into commercial practice:

1) Biosafety of transgenic stocks.
2) Patent law and business ethics.
3) Humanity and efficiency of the cloning process.

That's why I think it's can be so damaging that people get hung up on the cloning thing. They don't even get to thinking about the real issues because so many have already decided that the technique itself is "unnatural" and therefore poses some sort of danger food supply. It will probably pass - I think the public had similar concerns when IVF was introduced, and no one seems to be worried about that anymore. But nonetheless these are the types of knee-jerk fears that can lead to stupid and useless prohibitions on whole areas of research if they build up steam.

Bayman said...

In 3) I think I was trying to say "humaneness" or whatever the opposite of cruelty to animals is.:)

Greg. Tingey said...

Errr ...
Cloned meat has ben in the food chain for a VERY long time.

Every time you eat a cow or a sheep or a goat that is one of a pair of identical twins, then you have eaten a clone.

This is more of the insane "playing god" scaremongering.

AGRICULTURE is playing god.
MEDICNE is playing god.
CLOTHING is playing god.
ARTIFICIAL 9that is built) homes are playing god.

The Doc said...

An identical twin is a fundimentally different thing to an artificially induced clone - particularly if that clone has come about via nuclear transfer techniques. You do realise that, don't you?

I wholeheartedly agree that there is almost certainly no reason to be concerned about meat arising from a cloned animal.
However, this is the bloody food chain here - the stuff we like to eat, and all that.
Surely it'd be wise to make sure that the t's are crossed, and the i's are dotted? There may well be something quite important arising from epigenetics which is not understood yet. I don't know if/what they may be, but there is a distinct possibility.

I have absolutely no issue with people 'playing god'. I tend to play god a lot on my computer (not to mention in the lab), and have basically gotten over the shock of it.

kamel said...

Maybe a naive question, but do are the abnormalities in cloned animals fundamentally different from genetic/epigenetic aberrations that can happen naturally (other than frequency)? That is, is there reason to believe that a developmentally defective cloned cow with screwed up epigenetics differs from a similar cow produced the 'normal' way?

The Doc said...

My limited understanding of the details to that question is "we don't know".
It's known that embryos arising from nuclear transfer suffer huge epigenetic problems, but these tend to be the same kinds of problems that come out of normal epigenetic diseases.
The fact that they are there implies that the process isn't all it's cracked up to be, yet, and to me, that means we shouldn't be discussing the details of weather they are safe yet...

Larry Moran said...

the doc says,

It's known that embryos arising from nuclear transfer suffer huge epigenetic problems ...

Gimme a break.

We're talking about successfully cloned animals here. You know, the kind that look perfectly normal and can reproduce.

Do you honestly believe that these animals have "huge epigenetic problems" that pose a health risk? That's just nonsense.

The Doc said...

At no point did I state that they are known to cause health risks. Kindly don't add your interpretation to my words.

I stated that the process of cloning is not completely understood, and subtle changes in metabolic profiles is known to be associated, post cooking, with chemicals that are known carcinogens.

I then implied that BECAUSE THIS IS NOT UNDERSTOOD, it is premature to declare them totally safe.

I got some thalidomide for you. I hear it's great for a whole pile-o-problems. I've tested it for a few things, but who knows... it's totally safe.

Bayman said...

doc says,
I stated that the process of cloning is not completely understood, and subtle changes in metabolic profiles is known to be associated, post cooking, with chemicals that are known carcinogens.

I'm not sure I follow the parallel you're trying to make here between nuclear transfer and chemistry. Essentially the only **possible** difference we're talking about here is a different pattern of covalent modifications the to chromatin-associated DNA or protein in cloned meat. And even if the pattern is indeed different, the total quantity of each modified species in the cell is highly unlikely to differ significantly. So, I see no possible way the overall chemistry of cloned meat can differ from non-cloned meat. Getting meat from a clone is nothing at all like cooking it or lacing it with thalidomide.

BECAUSE THIS IS NOT UNDERSTOOD, it is premature to declare them totally safe.

Do you COMPLETELY understand the biology of everything you eat? Did paleolithic humans for that matter?

Food safety is not about knowing everything there is to know so you can somehow completely eliminate risks that you can't even imagine. In fact, both of these things are impossible. It's about common sense and minimizing risk.

You are quite right that it has not been categorically proven that cloned meat is completely safe. That standard shouldn't be the gauge you use to decide whether it's acceptable to eat, because it's impossible to achieve. Instead, you have to take everything you know about the technology and ask what is, theoretically, the space of all possible things that could go wrong here? It's totally irrational to decide to do or not do something because of a risk you
can't describe. It's like the monster under your bed that only comes out in the dark...

The Doc said...

My point was that I am suspicious (maybe needlessly) of a technology which is not yet as tried-and-true as some claim. There are differences between clones and 'normals', and this implies that more work should be done.

Again, I didn't explicitly state that I thought they were unsafe. My comments were to the effect that there are reasons to believe that they might not be, and these reasons are not "because it's a clone, and it's just not natural". It's not a case of a monster under the bed... it's a case of believing that this new technology should prove itself.

I agree, proving something completely safe is impossible. Has ANY testing been done to show that clones are safe?

A brief search of PubMed turned up a paper commenting on a difference in fatty acid composition between cloned and non-cloned cattle, and initial difference in immune responses to immunisations.
(Theriogenology. 2007 Jan 1;67(1):134-41. Epub 2006 Nov 7. - amongst some other papers) It's worth noting that this is not mentioned in the Nature Biotechnology paper on the risk assessment of cloned meat (Nat Biotechnol. 2007 Jan;25(1):77-83.).

While neither of these is going to kill you, it does indicate that there CAN be a change in chemical makeup.

Again... I've not said it IS dangerous, but that there are reasons to be cautious.

JGarlough said...

For me it's about variety & choice. In much the same way that I do not want a MacBurger every day for breakfast, lunch and dinner; I do not want to eat G A R EFFICIENCY 7295 clones every time I eat beef.

Supermarkets often label the breed or producer; my local butchers always know the breed and often know the farmer; and when my father gives me beef he knows the animal's breed, name, age, weight, health, and disposition.

Currently, I feel that's enough information for me to be able to choose what I want to ingest.

Whether or not cloning is safe/ethical/efficient, I would still like to know how the meat in the food I eat is produced.

Anonymous said...

OK, we had a reference to a good discussion on the biosafety of the GE corn ( I really don't agree that this pdf was very informative. In fact, I can truthfully tell you that there is radon in your drinking water and that radon can cause cancer. Both statements are quite likely to be true but not very informative because generally the levels of radon in drinking water are quite low. So I wouldn't expect you to stop drinking water, reduce your intake or even move to a community that has drinking water with "40% less radon". Now back to the GE corn which was described in this pdf to have high levels of lysine which upon cooking will lead to high levels of toxic carcinogenic byproducts. Now that sounds almost as nasty as that radon! What might happen if some of this corn made its way into our food supply?"...even small quantities of such substances pose food safety
risks..". Well the GE corn actually has only 40% more lysine than regular corn. Now unlike cattle, we have a lot of choice in our diet, so the chances of any of us getting stuck in front of a trough with nothing but cooked GE corn to eat seems remote and if it did happen I would be more concerned about my immediate quality of life as opposed to my increased risk of cancer! Also, if I were to apply the "logic" of this article fully, then shouldn't we all try to reduce our intake of lysine?

I do agree that new GM products need to be carefully regulated with a lot of lateral thinking about potential hazards and consequences, but articles like this are just designed to elicit fear by taking facts and presenting them out of context.

Now I have to decide whether to enjoy those baked beans for dinner tonight. Beans are a good source of lysine, and they are cooked so they will be toxic. Probably the greater concern will be the inevitable toxicity my colleagues will face tomorrow morning if I over indulge :)

The Doc said...

Not that I have to defend that group, but the link I provided was a lay summary/press release.

Here's the real report:

Again, I'm not saying that Clones are dangerous eating. I'm saying that dismissing any risk off hand is not, possibly, the most appropriate thing.

Bayman said...

I'm saying that dismissing any risk off hand is not, possibly, the most appropriate thing.

I'll certainly agree to that.

So Doc, would you agree with me that a categorical ban on the use of nuclear transfer technology in agriculture would be unnecessarily restrictive? And that it's ok for cloned meat to enter the food supply so long a consumers are made aware of its origins and so long as it meets normal food safety standards and regulations?

The Doc said...


Completely. Bans are rarely the best way to achieve anything. I'd also like to ensure that there is a good independent body (i.e. not the FDA) who were keeping a good eye on the field.

I also don't think that the possible risks from cloned food are worth worrying about... versus all the other things which people do and which will kill them.