I thought you'd find this as interesting as me, the ways science can be reported - the need not to jump to conclusions too soon. Having said that, no way would I trust corpo- rations/multinationals or anybody with financial interest to make decisions for my future health/safety/environment. Eva > > I am impressed -- as ever -- by the amazing way too little information can > be made worse for the reader (and better for the writer and his opinions) > than enough information. Stunned, even, in this case, since I have > first-hand knowledge of the stuff being discussed. > > For instance, the thing described in this article as "Jeff Palmer's" > "genetic parasite" is a DNA sequence of about 2000 base pairs (if I recall, > since I am one of many botanists who actually sequenced part of the damned > thing, back when I was a budding molecular botanist in the summer of 1987) > called a *transposon* or *transposable element*. These are the things that > make leaves of some green plants have white blotches on them, and make what > we call in this country "indian corn" have little red or purple radiant > stripes on the kernels of some varietals. They have an interesting history, > evolutionarily, since they are most likely the origin of viruses (i.e., all > of them), and control expression of whole suites of genes in very > interesting ways. They are what Barbara McClintock got her belated Nobel > prize for. > > All higher (eukaryotic) organisms have transposons. Always have, > apparently. And there's always been some suspicion of horizontal gene > transfer. What I was sequencing during my golden youf was a close relative > of this article's particular transposon, which turned out to be nearly > identical in carrots and in rice -- which are not very closely related, > phylogenetically. 'Tis to say, we pretty much knew that the DNA had got > from one to another way back then, without being directly inherited. > > >A group of researchers in Indiana University of the United States, headed > >by Dr. Jeffrey Palmer, have just reported in the current issue of the > >Proceedings of the National Academy of Sciences USA that a genetic parasite > >belonging to yeast has suddenly jumped into many unrelated species of > >higher plants recently. > > But the **best** thing I like about this article is the word "recently" and > the word "suddenly". Amazing, actually. Know what it means, really? I quote > from the abstract of the article in question: > > "Extrapolating to the over 13,500 genera of angiosperms, we estimate that > this intron has invaded cox1 genes by cross-species horizontal transfer > over 1,000 times during angiosperm evolution. This massive wave of lateral > transfers is of entirely recent occurrence, perhaps triggered by some key > shift in the intron's invasiveness within angiosperms. " > http://www.pnas.org/cgi/content/abstract/95/24/14244?maxtoshow=&HITS=10&hits=10& > RESULTFORMAT=&author1=palmer%2C+j.+g.&searchid=QID_NOT_SET&FIRSTINDEX= > > Check it out -- "during angiosperm evolution". This being a *very long time*. > > >This parasite is a piece of DNA called a group I intron that can splice > >itself in and out of a particular gene in the genome of mitochondria. > >Mitochondria are little power houses of the cell that oxdize food in order > >to turn it into a form of energy that can be used for all living processes. > >Until 1995, this parasite was thought to be confined to yeast and only one > >genus of higher plants out of the 25 surveyed had the parasite. But in a > >new survey of species from 335 genera, 48 were found to have the parasite. > > "Until 1995 this parasite was thought to be confined..." my ass, not to put > too fine a point on it. It wasn't "unknown" -- I know a man who got his > Ph.D. in 1988 for showing how it worked in rice, wheat, and carrots. > Admittedly, that was a version in the coxII gene, but what the hey? Same > idea. > ... > > >· Is it possible that the recent massive horizontal gene transfer from > >yeast to higher plants was triggered by commercial genetic engineering > >biotechnology itself? > > Here, students, we see what is perhaps the best rhetorical use of > incomplete information. Note how we have moved laterally from never saying > what "recently" means to the actual researchers (at least several tens or > hundreds of thousand years) to what the author of this "review" feels it > "should" mean to the now worried reader. Shift and separate. > > >· Genetic engineering makes use of artificial genetic parasites as gene > >carriers, to transfer genes horizontally between unrelated species. These > >artificial parasites are made from parts of the most aggressive naturally > >occurring parasites like the group 1 intron discussed here. > > And this phrase "genetic parasite" is a fascinating coinage in its own > right. While strictly speaking it is absolutely accurate, its X-filesian > connotation gives it a very high score on the rhetorical scale. One could > as well speak of the insidious use of cell-death-inducing "destructor > genes" in creating things like, oh, fingers (the bits of the very little > baby you that used to live between your fingers are no more, alas, thanks > to these perfidious perils of nature). "Transposon" doesn't have nearly the > same inimical air. > > >· We should take this new evidence very, very seriously. There should be an > >immediate moratorium on further releases of transgenic plants, in > >particular those carrying antibiotic resistance genes like the Novartis maize. > > Take-home lesson: The arc from the bow of disposition to the target of > conclusion is often blocked by the presence of too many facts. > > Caveat lector: As some readers will know, I am more usualy filled with > amusement than with vitriol when presented with such bollocks. In this > case, however, knowing the people, the organisms, the science, and the > goddamned DNA in question... well. Nuff said. > > To answer the question: (B) Fodder for the technophobs, I'd say. > > Regards, > Tozier > -------------- ------------------------ > William Tozier [EMAIL PROTECTED] > http://www.santafe.edu/~tozier > Joint Web Editor: Alife Online http://alife.santafe.edu > > "Victory goes to the player who makes the next-to-last mistake." > -- Savielly Grigorievitch Tartakower > > -- > Terry W. Colvin, Sierra Vista, Arizona (USA) < [EMAIL PROTECTED] > > Home Page: < http://www.geocities.com/Area51/Shadowlands/8832 > > Sites: Fortean Times * Northwest Mysteries * Mystic's Cyberpage * > U.S. Message Text Formatting (USMTF) Program > ------------ > Member: Thailand-Laos-Cambodia Brotherhood (TLCB) Mailing List > TLCB Web Site: < http://www.seacoast.com/~jsweet/brotherh/index.html > > Southeast Asia (SEA) service: > Vietnam - Theater Telecommunications Center/HHC, 1st Aviation Brigade > Long Binh, Can Tho, Danang (Jan 71 - Aug 72) > Thailand/Laos > - Telecommunications Center/U.S. Army Support Thailand > (USARSUPTHAI), Camp Samae San (Jan 73 - Aug 73) > - Special Security/Strategic Communications - Thailand > (STRATCOM - Thailand), Phu Mu (Pig Mountain) Signal Site > (Aug 73 - Jan 74) > >
