Saturday, 19 September 2015

GM debate : ignorance of reality is no defence.

And now we have a bunch of gene spliced pollen floating around the countryside fertilising next years seed corn.

To prevent stray pollen the Rothamsted scientists have surrounded the trial plots with 10 metres of barley and three metres of conventional wheat.
No cereals or grasses are grown within 20 metres of the border. Wheat pollen is heavy and travels at most 12 metres.

These precautions @fizzgog are totally inadequate to prevent contamination. They have been conceived within the wrong paradigm, they are designed to reduce the statistical likelihood of a single pollen grain passing to a food crop but where you are dealing with billions of pollen grains in a real world situation, a small statistical chance for one grain becomes a statistical inevitability for many many thousands.

It bears comparison with the reason that the Nazis did not develope the nuclear bomb, they believed the statistical likelihood of a single neutron collision required that it travel through many meters of plutonium, what they didn't consider was what the allies understood, which is that not all the neutrons need to collide to generate a self sustaining fission chain reaction. Only a smaller proportion need to collide, a statistical inevitability where billions are involved. Their huge error meant they believed a nuke had to be made of tonnes of material and so they did not persue the idea when in fact the critical mass for plutonium 239 is about 11 kg.

These field trial precautions fall foul of the same kind of mistaken interpretation of statistics. The contamination of the food crop with genespliced pollen was inevitable using these protocols, it has already happened.

Consider the case where there is a local eddy which can pick up much heavier objects than a breeze and transport them to altitude thus moving them far further than laboratory based experiments predict. This is due to the low pressure tube which forms at the middle of any vortex and sucks in medium like a vacuum cleaner. They dont have to big, even a dust devil would shift pollen a lot further than 12m and a strong turbulent persistant wind will tear the lab based statistics for pollen distribution to shreds as turbulence creates multiple chaotic vortices. Its absolutely unconscionable to expose the UK countryside to experimental windborn GM pollen.

Not even one grain of pollen should be allowed to escape. Genetic contamination does not require that a whole field be pollinated, it requires only that one seed planted for next years crop be fertilised by this years genespliced pollen.

flyingfox (aka boolybooly)
The article above is predicated on a straw man argument. Many GM critics are highly qualified and well informed biologists. The people doing GM work are not all of the same caliber and have been hired by profit motivated companies flush with finance to play with forces they do not seem to understand. 
The design of this experiment was negligent and unsafe and has ensured that modified genetic material will have escaped into the environment and will now become part of the wheat crop in the UK whether it was successful or not, whether it was safe to eat or not, we will soon be eating it.

Critical Party

I assume that the critic "scientists" you're referring to are people like Seralini, Carmen, and Seneff? People that have been thoroughly lambasted for poor science by regulatory agencies across the board. 
Also, your second paragraph is hilarious. Your knowledge of how genetics works is clearly completely nonexistent.

I am afraid you have that backwards, it is you who does not understand. I am not trying to slap you down or anything but FYI and because you brought it up I have studied evolution and genetics at a reputable academic institution :) please feel free to troll away if it makes you feel good.
If ignorance is no defence in law, it certainly will not protect us from reality. The experimental design ensured that wind borne pollen has escaped, it does not take a field full of GM wheat for next year's wheat crop to be contaminated, it takes only one pollen grain to fertilise one seed and for that seed to be planted among next year's crop for the genetic modification to become established in the food crop gene pool. The theory of evolution by natural selection depends on the possibility that mutations happen only once but can be inherited by an entire species due to the process of gene fixation. This is because where one individual organism reproduces it can create more than one offspring eg the many seeds (and pollen grains) of a wheat plant seed head. Where offspring inherit an advantage they will reproduce better than competitors without that advantage, but even where a genetic difference confers no advantage the frequency of GM chromosomes will still persist in the gene pool alongside competitor non GM chromosomes and can potentially increase due to a process termed "genetic drift". We know this already.
However the conception of this experiment has been criticised on the basis that aphids respond to changes in pheromone concentration, so are not deterred by an even and constant spread of the chemical across an entire field ie they become habituated to a constant concentration and only respond to a sudden increase signalling an alarm. Where contaminating seed grows in an environment where it is one plant among many without the modification it might potentially be granted an advantage not evident in the experiment precisely because it is present in small numbers within a host crop, creating localised maxima of pheromone concentration so that an aphid arriving at a GM plant will encounter a relative rise in alarm pheromone and be repelled to nearby plants without the pheromone, which means that there may be a selection pressure which will raise the frequency of the contaminating GM genotype to an equilibrium point within the gene pool where it no longer confers an advantage because too many neighbours have the same pheromone. Such a gene would never reach fixation in a monoculture crop but would never be extinguished either because where it became rarer it would become advantageous again and so would always be present.
The point is we don't know whether this can happen but the lab experiments suggest it is a possibility. But that is the point, ignorance is no defence in reality. These field experiments should never have gone ahead in the open without proper laboratory background research into the phenomena they are trying to exploit. In this case the failure shows the experimentation had not been done adequately.
But there are also other real world reasons for caution which are being completely ignored by open air experimentation. All GM product should be treated as biohazard until food trials have been conducted to ensure pleiotropic effects or the reawakening of epigenetically suppressed genes has not allowed any carefully bred out plant defences or other toxity to result. They should certainly not be allowed to contaminate food crops. I fear it will take a disaster on the scale of an industrial accident for biotech companies to take genetic safety seriously.
These companies are playing biological roulette with your daily bread. With this trial the damage has already been done and we will just have to cross our fingers and hope for the best. There is nothing else we can do except ensure that local wheat farms for a 5km radius do not allow their wheat to be used for seed next year.

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