On 17 Nov 98 at 12:00, Margaret Lauterbach wrote: > I stand corrected, Liz. I've had that post for at least three > weeks,a nd should have re-read it. Margaret I'm not sure what you stand corrected about -- I just reformatted the post to make it legible. Please note that this post was written by a publicist, not a scientist. I'm responding to it under the assumption that a publicist got it right. (Ha!) I have one serious reservation without giving the issue much thought -- it's the implicit assumption that the only key to fit in the lock that turns on sterility in these seeds is tetracycline. Apparently, the "terminator" genes are activated by tetracycline as the designers intended. That does not mean that other chemicals, naturally occuring or synthetic, will not turn on the terminator gene. This is a very, very serious issue. Activation of the genes by tetracycline was, apparently, designed as a fail-safe. The guarantee that "terminator technology" won't escape and "destroy life as we know it" is based on the idea that the technology won't work unless activated. If the activator is not found in nature then it doesn't matter if the terminator gene escapes -- without activation it is harmless. The idea is that only something "exotic", i.e. not found in nature, will activate the gene. The problem is that there may be more than one chemical that acts so as to activate the gene. Another chemical with a shape similar to part of a tetracycline molecule could, and probably would, act to activate the gene, too. There are millions of naturally occuring chemicals out there along with hundreds of thousands to millions of synthetic chemicals. It is likely that in the chemical warehouse that is Mother Nature there are dozens of chemicals capable of turning on the terminator gene. In other words, just because tetracycline turns on the terminator gene in no way indicates that 1,3,5-triphenylformazan, or some other chemical, doesn't turn on the terminator gene. This lock could have dozens of keys, some of which are naturally occuring substances. I don't wonder about the experiments that showed tetracycline turns on the gene -- I wonder if they bothered to test more than a dozen of the millions of other chemicals out there to discover if they also turn on the gene. After all -- a tomato contains dozens of chemicals (many of which are toxic). Lemons and oranges have seeds that sit in the natural equivalent of an acid vat. There are alkaline soils and aquifers in the western US and goodness knows what conditions in other places on earth, including temperature and humidity extremes. So millions of chemicals could come into contact with terminator seeds under dozens of different conditions and different pHs for differing periods of time. Talk about the way to run a lottery! I wouldn't really want to bet that the only working key for terminator technology is tetracycline applied at the seed factory. The fail-safe to prevent the spread of the effects of the terminator gene is, by my way of thinking, insufficient on it's surface. As a chemist, based on what little information I've gotten, I couldn't support releasing this technology. Perhaps, instead of the pandering pap about growing food in harsh conditions for starving people -- what we're offered here as a reason for considering this sort of technology -- good old Uncle Sam could come up with a way to get people to practice birth control. That way we could grow plenty of food on the good, arable land that exists in moderate climactic areas. And people could have lots of fun doing the research, too. Heck, call me a lunatic idealist and invite me to dinner with Florence King, but I think there are way more people on this planet than we need (as well as way, way too many people that Ms. King wouldn't want to dine with). We need less people, more biodiversity and more open spaces. Liz chemist in retirement