Reply #103: no, I don't agree with that, but I'll be happy to clarify....

[mike_c]

Actually, I have no objection whatsoever with labeling cloned foods-- although at present, the only foods that would bear such a label are most fruits and vegetables, whether fresh or prepared. Will you not be eating anymore of those, either? That's your choice of course, and I'll support you either way.

I think the real issue has to do with exactly the same sort of hysteria we've seen throughout this thread. Turn the argument around and consider it from another perspective, if you will. If you PRODUCED cloned meat, how would you react if consumers avoided it unreasonably? If they refused to buy it because they were afraid to eat it, even if there was no reason to fear it. In that case, the LABEL becomes the only impediment to consumption, not some underlying condition that requires labeling to insure consumer protection. The only persons with potential to be harmed are the farmers and the food production industry.

Stated another way-- food causes obesity, so should all food be labeled with a cautionary statement that eating it will make you fat? That's ridiculous because such a label would cause economic harm without actually solving any problem because there isn't really a problem to solve.

I do agree with you that consumers deserve the choice, and that everyone should know as much as possible about their food supply. But again, we presume they will use that information reasonably, not hysterically. If there is a known high probability that labeling will do harm to the producers without solving any real problems for consumers, is it reasonable to demand labeling just so that consumers can indulge their irrational fears?

You must admit that much of this stems from poorly informed consumers who react to buzz words like "cloning" or "genetic modification" without having any clear idea about what those things are. Some in this thread have suggested that cloned organisms might cause cancer-- what OF all those cloned fruits and vegetables we've eaten for thousands of years?-- or that they "screw with your genetics." These sorts of responses are knee-jerk at best. They demonstrate a shocking level of biological illiteracy, yet they are probably just what awaits any product labeled "cloned" at the supermarket, including the apples and oranges we've eaten for generations without harm.

OK, some specific replies:

But you have absolutely no way of knowing that the meat is safe.

First, I likewise have no reason to suspect that it's not, but more important, I do indeed have every reason to believe that it's safe. Clones grow just like any other organism, by cell division and self assembly, and they have exactly the same system integrity checks working along the way at levels from the biochemical to the organismal. Cloning is just another form of reproduction-- after that event, everything proceeds normally. I can say with absolute assurance that the tissue of cloned organisms is not different from the tissues of organisms propagated sexually, or at least that there is nothing implicit in clonal reproduction that makes it any different.

I am, however, amazed to find out that scientists thousands of years ago were able to extract plant DNA from a mature plant, insert it into a plant embryo, and grow an exact replica of the original plant. I guess I thought the technology to extract DNA was a modern one.

Is that just snark, or were you really unaware that plants are frequently reproduced clonally? Your subsequent comments about cuttings make me suspect the former, so I'll assume you know the difference between totipotent cells and non-totipotent cells. Totipotency is the only reason plant clones propagate easily from tissue samples and most animal clones do not (there are animal exceptions, we just don't eat them). Anyway, in animal cloning it's a somatic cell nucleus that's "extracted," not naked DNA (although that would not make any real difference anyway). Extracting the nucleus is mainly just a matter of being able to manipulate small, soft objects under a microscope-- that's the bulk of the technology, just handling tiny, fragile objects. The DNA itself was created by the donor cell in the usual manner, completely and utterly naturally. That process is performed as a substitute for the totipotency exhibited by plant cells-- again, nothing particularly "new" in a conceptual sense, just improved ways to physically handle tiny things. However, there is no fundamental difference between "sticking a cow's tail in the soil" and replacing an ovum's nucleus-- the end result is that a new organism assembles itself from a small number of starting cells. We can't do the former because plant cells are totipotent and animal cells aren't. BTW, the reasons for that make a fascinating evolutionary discussion, but are OT here.

And the reason food animals have shorter lives is because we slaughter them when they are young, before they have a chance to develop age related illnesses like cancers, mad cow, etc. From what I understand, cloned animals age prematurely.

Your first statement was precisely my point: it makes little difference whether cloned food animals have shorter life spans because they're going to be slaughtered early anyway. As for the second, that is a developmental biology issue and an animal husbandry issue that I don't think has much to do with the suitability of cloned organsims for food. Current evidence suggests it has much to do with gene expression when a fully determined, non-totipotent nucleus is "reset" in the ovum, i.e. that the resetting is perhaps imperfect or incomplete (there are some other possibilities as well). Again, IF the animal completes its normal self assembly process, it should be no less suitable for consumption than any other animal slaughtered at the same physiological age.

And if a cloned animal ages differently from a normal one, how many other undetected differences are there which could theoretically be health concerns?

Bear with me here, because the first part of my answer will make alarms ring.

How many? The possibilities are nearly endless. There could be MANY undetected differences that could be possible health concerns. However, just about all of those would be health concerns for the animal long before they could ever impact humans by entering the food chain. Just about anything that that could originate in an animal's metabolic machinery that will affect OUR health will affect most other mammals as well, including the one expressing the aberrant biochemistry. Sure, they might still go undetected, but most COULD be detected, and many would be hard to miss. And again, the animal still has to self assemble all the way from a single cell, so if it's successful, the chances are overwhelmingly that it is safe to eat.