Global biopharming01 Jun 2007
Planting time has arrived in most of the country -- even here in zone 4 -- so you may be reading those seed packets carefully. This paragraph may catch your attention:
One anti-biotech group even managed to bamboozle some seed companies that cater to home gardeners into signing on to something called the Safe Seed Pledge: "We pledge that we do not knowingly buy or sell genetically engineered seeds or plants." This is fascinating because, with the sole exception of wild berries and wild mushrooms, all the fruits, vegetables and grains in North American and European diets have been genetically modified or engineered by one technique or another. This even includes 'heirloom' varieties of fruits and vegetables. Often, this genetic modification has involved radical changes at the level of DNA, including the movement of genes or even entire chromosomes across natural breeding barriers.
That's from a TCS Daily column by biotechnology analyst Henry Miller. This is a point that constantly amazes me -- do people not realize that it is unnatural to have purple potatoes and zebra-striped tomatoes, and all other manner of garden mutants? That, for the most part, it is unnatural for vegetables (i.e., non-fruit and non-seed plant parts) to be tasty and delicious? Plants don't want you to eat them!
Most of the column is devoted to reviewing some of the misleading parts of a recent report on international biotechnology trends by the Organization for Economic Cooperation and Development. It's a fair critique, but a little dry for light reading. Certainly it's valuable to have critics go through definitions in these international reports, because so much of the conclusions are essentially determined by the assumptions that go into compiling lists. Some countries look different than others, just because their regulatory agencies define things in different ways.
I approach this issue from the perspective of teaching the debate in my genetics course, and also as a way to examine how the debate around human genetic engineering may be framed in the future. After all, franken-people are bound to be a lot more interesting than franken-food.
Not to mention the possibility of Neander-people -- or, dare I suggest, NEANDER-FOOD!
I find the trend toward GMO production of pharmaceuticals to be a very interesting angle in the current biotechnology scene, because of the clear resonance of the issues with human genetic alteration. Both the opposition and promotion of GMOs have both involved heterogeneous groups of interests. Much of the muscle behind both positions has come from agriculture industry groups -- So far, the critics of GMO deployment have been successful when they frame their opposition in terms of risk of introgression into non-GMO crops or wild plants. They have also had success with the "natural food" frame.
A month or so ago, I referred to an article that discussed the potential of introgression by plants genetically engineered to produce pharmaceutical compounds. Quoted in the article, Norman Ellstrand asked, why not modify non-food plants, and thereby eliminate all risk of consumption?
In his article, Miller gives an answer to this question:
Although there is substantial and growing acreage of gene-spliced crops cultivated worldwide each year - 252 million acres in 2006 - more than 90 per cent of it is four large-scale commodity crops; largely because of the huge costs of meeting regulatory requirements, the application of the technology to fruits, vegetables and subsistence crops has been minimal, and disappointing.
In short, it is easier to get approval for altering one of the four major food crops, because they have a research history and are already grown on a immensely large scale. Introducing genetic modification on another kind of plant requires much more work to conform to regulations.
There is also the issue of a less-recognized mode of genetic modification; namely, Simpsons-style:
Currently, dozens of genetically improved varieties that are produced through hybridization, irradiation and other traditional methods of genetic improvement enter the marketplace and food supply each year without any governmental review or special labeling. A technique in use since the 1950s, induced-mutation breeding, involves exposing crop plants to ionizing radiation or toxic chemicals to induce random genetic mutations. These treatments most often kill the plants (or seeds) or cause detrimental genetic changes, but on rare occasions the result is a desirable mutation. For example, a mutation might produce a new trait in the plant that is agronomically useful, such as altered height, more seeds, larger fruit or enhanced resistance to pests.
On a large scale, these random mutations pose more potential of introgressing into wild plants, because they don't carry the baggage of a plasmid, and they might have unknown beneficial side effects on plant fitness. Plus, a strain bearing many random mutations might have some unintended ones along with the one that is strongly selected by subsequent breeding. This kind of induced-mutation breeding is really nothing more than ordinary breeding sped-up a little faster, but then, the only thing making trans-species gene transfer different is that you know in advance that the inserted gene works in some other organism.
In a previous column, Miller argued against legislation being considered to regulate the farming of gene-spliced plants in California. At the same time, he points out the harmful consequences that sometimes result from conventional breeding:
This measure is pointless. In the production of new plant varieties using conventional - that is, pre-gene-splicing - techniques, breeders, farmers and food producers lack knowledge of the exact genetic changes that produced the useful traits. More important, they have no idea what other changes have occurred concomitantly in the plant -- including those that could alter the ability to cause allergic reactions.
Only the molecular, gene-splicing methods allow breeders to identify and fully describe the changes that have been made in the progeny, so perhaps it isn't surprising that only the imprecise, trial-and-error techniques of conventional plant-breeding methods have led to food safety problems. Two conventionally bred varieties each of squash and potato and one of celery were found to contain dangerous levels of endogenous toxins and had to be barred from commercialization. Such mishaps are far less likely when genetic changes are wrought with the more precise and predictable gene-splicing techniques.
The difference is not mainly that the trans-species genes are predictable in effect, but that they are introduced only a few at a time. This is less likely to cause incidental side effects than altering the frequencies of many genes by conventional breeding. The point is that anything that we change may generate bad side effects, and we want to find ways to minimize these. One approach is not to change anything. But since nature changes things for us anyway, maybe best to change with science...