Volume 7 Number 35 Subjects Discussed In This Issue: Genetic Engineering (Tomatoes and Pigs and Arctic Flounder) [Aimee Yermish] Non-Kosher-Tomatoes [Bob Werman] Pig Tomatoes [Seth L. Ness] Pigness (3) [Joel Kurtz, Yisrael Sundick, Hillel Markowitz] Pigs [Zev Farkas] ---------------------------------------------------------------------- From: <ayermish@...> (Aimee Yermish) Date: Tue, 11 May 93 16:25:17 -0400 Subject: Genetic Engineering (Tomatoes and Pigs and Arctic Flounder) Maybe I can help clear up a few of the questions about genetic engineering. (In real life, I'm a grad student in Cancer Biology, and while I've never engineered a tomato, much less a pig, I am familiar with the techniques and technology, as well as with the basic biology) Eitan's assurance that there is no one gene that makes a pig a pig, that its essential "pigness" is defined by "a complex interaction of countless genes," is right on the money. You can't mutate one pig gene and get a cow. In fact, it's pretty tough to mutate one pig gene and get anything that doesn't *very* strongly resemble a pig (assuming the creature survives to the point where you can see it). Not only that, it's pretty tough to mutate a large number of pig genes and get anything which survives which doesn't very strongly resemble a pig. Even the simplest little things about pigs are governed by a large number of genes, about which we know next to nothing. From the standpoint of a biologist, the idea that there would be one gene which would confer "pigness" is patently ridiculous. Another potentially relevant point which has not yet been mentioned is the issue of homologous genes. Many (if not most) of the genes in a given organism have homologs in related organisms. The more closely related the two organisms (pigs and cows, for instance, are pretty close in the grand scheme of things), the more their genes resemble each other. We humans have genes which are homologous to genes in yeast, believe it or not, and the genes have basically the same functions no matter what organism they're in. Chances are pretty good that the protein encoded by the pig gene actually has a functional homolog in the tomato, but the tomato version is regulated differently or has subtly different activity. If the pig protein were all that wildly different, it might well not be able to interact with the existing tomato proteins, so there wouldn't be any noticeable change in what the tomato looks like to us. (Before you jump on me, yes, the artic flounder gene is probably not required to interact with much of the tomato machinery, so this comment may not apply too tightly) Speaking of that artic flounder, the "essential characteristic quality" which Daniel worries might be transmitted to the tomato, is shared by many cold climate species, and if I recall correctly, that goes for the plants as well. They all have the same problem to solve -- keeping their innards from freezing -- and they do it in remarkably similar ways (many of them probably inherit their solutions from common ancestor species). Why do they pull the genes out of such bizarre animals? Historical accident. That's where they first found a gene that they thought would do the thing they wanted. Bob comments that we are prohibited from touching the carcass of a pig. The tomato which you eat was produced entirely by the tomato plant, eating sunlight and soil nutrients. The seed from which that plant grew was produced entirely by another tomato plant. There was a seed a long time ago which was given a piece of DNA (actually, I suspect that it was given to a plant which was about to produce a seed) which coded for the pig gene, probably modified to make it work better in the tomato environment and/or to make it easier for the investigator to figure out which seeds had picked up the DNA. That DNA was almost undoubtedly produced entirely by a bacterium, which eats various raw chemical junk, usually dead yeast and the like. (there are probably several generations of DNA produced in bacteria at this point, but I'll leave them out for clarity). A long time ago, that piece of the DNA which is derived from the pig was probably isolated from a bacteriophage (a virus which parasitizes bacteria and which is very useful to people looking for genes). The bacteriophage got the DNA from an in vitro (in glass, that is, in a test tube rather than in a living organism) reaction where a researcher took pig RNA and gave it to enzymes which would make a DNA copy of it suitable for further use in lab. Only all the way back here do we get pig RNA that is actually purified from a real, live, oinking pig. I'm not a scholar of halacha, but I would suspect that this many-generations-removed distance is far enough for the tomato to no longer qualify as a pig carcass. As a biologist, I am constantly dismayed by the treatment of genetic engineering ideas in the popular press. There is very little coherent reporting on the subject (or on any scientific subject), and I've often been hard-pressed myself, on listening to these reports, to figure out just what it was they were talking about. I shuddder to think how confusing it must be to people who don't have the training. I'd be happy to explain in more detail any of the topics I've just covered, or any other biological topics on which I feel I can speak with confidence -- just send me private mail and ask. --Aimee ---------------------------------------------------------------------- From: <RWERMAN@...> (Bob Werman) Date: Tue, 11 May 93 06:44:01 -0400 Subject: Non-Kosher-Tomatoes In view of the recent discussion on the kashrut of tomatoes [with genetic material from pigs], I think it of interest to point out that the tomatoe was considered unkosher in part of Poland for several hundred years. That was not a genetic issue but a question of enchanting, it seems. The tomato was universally considered an aphrodesiac in Europe, pomme d'amour, etc; even in Hebrew the name, agvaniya is derived from agavim, love-making. [eyin-gimel-bet] __Bob Werman <rwerman@...> rwerman@vms.huji.ac.il Jerusalem ---------------------------------------------------------------------- From: Seth L. Ness <ness@...> Date: Tue, 11 May 93 00:19:12 -0400 Subject: Pig Tomatoes daniel geretz says.. >Is genetic engineering comparable to the formulation of foods; i.e., can >the genetic material which is being put in the tomato be considered an >"ingredient"? If so, then the *source* of the genetic material >definitely should matter, even if it *could* be derived from other >sources or synthesized. (At least this is my understanding with respect >to enzymes and such other items that are routinely put into our food - >the medium/culture in which the enzyme is "grown" does seem to matter, >even if it *could* be manufactured some other way) Thats precisely the point here. The source of the enzyme and the DNA is the tomato, not the pig. the odds that even one atom from a pig is present in any tomato is so unbelievably remote i can't imagine it. Not only *could* it not be derived from a pig, it *is* not derived from a pig. Its derived from carbon dioxide in the air and nitrogen in the soil. If it is the medium/culture that is important then that medium/culture is the tomato. Seth L. Ness Ness Gadol Hayah Sham <ness@...> ---------------------------------------------------------------------- From: <kurtzj@...> (Joel Kurtz) Date: Tue, 11 May 93 15:38:10 EDT Subject: Pigness I would like to offer a response to Dan Shimoff in respect of the adoption of the pig as the representative of an entire class of unkosher animals. The animal fitness requirements enunciated in the Torah are twofold: (1) that it have a cloven hoof, and (2) that it be ruminant. Now, as I understand, pigs are unique among mammals in that they satisfy the first criterion, but not the second. Lest we are misled into believing that somehow pigs are less objectionable than, say, hyraces, tradition has conferred on the pig an extra measure of repugnance. I believe that the Yiddish term "chazer feesel" represents a parody of the "view" that since the hoof of the pig is cloven, then that part of the pig is acceptable. I welcome any and all responses to my thoughts on the pig. Joel Kurtz ---------------------------------------------------------------------- From: Yisrael Sundick <sas34@...> Date: Tue, 11 May 93 16:25:28 -0400 Subject: Re: Pigness I believe, the pig is either the only animal which has cloven hoves but doesn't chew its cud. In other word, it has the outward characteristics of a kosher animal, but fails in the inner characteristics. There is of course a tremendous amount of mussar to be learned from this. There is also a midrash which states that in the time of the moshiach, the pig will become kosher. presumable,it will begin to chew its cud. there was a big deal made a few years ago, when a claim was made of some african pig which did in fact chew its cud. * Yisrael Sundick * Libi beMizrach VeAni * * <sas34@...> * beColumbia * ---------------------------------------------------------------------- From: <H_Markowitz@...> (Hillel Markowitz) Date: Tue, 11 May 93 17:21:24 -0400 Subject: Re: Pigness >Whenever Jews talk of non-kosher animals, the pig is always used. What >makes the pig the quintessential unkosher animal? I don't think this >stems from the Torah, since no one I know thinks to mention a camel, >rabbit or hyrax, those animals mentioned with the pig as animals not to >eat, when talking of non-kosher animals. And, as Bob points out, we >have special restrictions on pigs too (I think there is a prohibition >about raising pigs in the land of Israel). > >Why has the pig been singled out? > >(<shdan@...>) Dan Shimoff I would say because the pig is unique in that the "outer sign" (split hooves) are there and it is only the "inner sign" (maalei geirah - note from other articles may not be literal cud chewing as in a cow) which is missing. I have seen the pig used as a metaphor for hypocrisy and also as a metaphor for the Xian missionaries (with a picture of the pig lieing with it feet outstretche so the hooves are visible). Another reason would be that the pig is a food source in locations where it is grown. Its only purpose is a a food animal as opposed to the camel (transportation) and the rabbit or hyrax (non-domesticated animals and not major food sources). THus when speaking about a nonkosher meat producing animal the pig is the main one to come to mind. Note that this can also be a reason fo not allowing them in Israel. The ONLY purpose is to grow them as a source of nonkosher meat. Hillel Markowitz <H_Markowitz@...> ---------------------------------------------------------------------- From: Zev Farkas <farkas@...> Date: Tue, 11 May 93 10:52:52 -0400 Subject: Pigs A few issues back, someone spoke about a prohibition on touching the carcass of a pig. Is this an actual prohibition, or does it just mean that one who touches the carcass of a pig is "tameh" (ritually impure, for lack of a more precise translation)? Does this apply to leather? How about other animals (horses, camels...)? (If I had a pair, would I have to give up my Hush Puppies?) Also, Jay Shayevitz speaks of porcine heart valves, and says that the preparation technique (marination in formalin, if i remember my cardiology) renders them permissible. I don't see where this is relevant. Surgical valve replacement is certainly not "derekh akhila" (the normal way of eating), and so is not covered by the laws of kashrut. (Similarly, much of the insulin in use comes from pigs and improperly slaughtered kosher animals - even if this were not a life-or death issue, it should be permissible since it is administered by injection, not mouth.) Just to throw another monkey wrench into the machinery: does the use of blood products or biopsy specimens from animals constitute "ever min hakhai" (the limb of a living animal) ? Does this prohibition only apply to eating, or any use? Zev Farkas, PE :) <farkas@...> 718 829 5278 ----------------------------------------------------------------------
End of Volume 7 Issue 35