A GM crop of greed
Last week, the British government announced that it would approve a strain of genetically modified maize, but would not allow the planting of similarly modified oilseed rape or sugar beet. The decision was said to be based on environmental considerations. The maize promoted biodiversity, the rape and beet reduced it.
For biodiversity, read weeds. The environmental damage at issue is exactly the same as the damage you do with a hoe in a flower bed. Weeds were well controlled in the trials of GM rape and beet. But the field with GM maize displayed more "biodiversity" than its non-GM counterpart - there were species in it the farmer had not intended to be there. This was because a more powerful, and soon to be restricted, herbicide was used on the non-GM maize.
I am not kidding. I wish I were. These experiments could not conceivably have produced data to support or allay public worries about GM crops. There is no reason for anyone to have changed their mind about GM after hearing these results, and no evidence that anyone did.
The background is a loss of public confidence in the commitment and competence of government to promote food safety. This problem is most acute in Britain, where official statements about "mad cow" disease and foot- and-mouth disease were subsequently found to be unjustified and untrue. Rebuilding trust will be a slow process. It will not be achieved through specious experiments. At best, the GM trials were a comprehensive waste of time and money; at worst, a sham to allow ministers to claim scientific support for political expediency.
Humans rightly feel uneasy about playing God in the creation of new species. But the juicy steak, the nourishing wheat grain, the loyal dog and the affectionate cat never existed in a state of nature. They are the product of generations of selective breeding and hybridisation. The development of new strains of hybrid corn - the green revolution - has been the single most important factor reducing world poverty in the past 50 years. We have engaged in genetic manipulation since agriculture was invented.
Through selection, hybridisation and GM you can create new varieties that are dangerous and life-threatening, or you can create varieties that are better and safer to eat. The search for generalisations about the consequences of GM for health and the environment is as foolish as asking whether scientific research is good for health and the environment.
If government policy is cynical and foolish, the same is true of the groups that campaign against GM. They have largely abandoned attempts to present specific arguments about adverse consequences of GM crops - wisely so, since there is no evidence of such adverse consequences. It is easier, or at least less intellectually demanding, to chant slogans and trample fields planted with GM crops and to profess concern about pollution - the contamination of natural products through the spread of GM. But the analogy is false: GM is a technique, not an additive that scientists mix into our food. Opponents of GM exploit public ignorance to stimulate vague unease that has no substantive basis.
And yet the actions of the companies that promote GM are, if possible, even more cynical and foolish. Throughout history, people have embraced new technology when it has offered better products or lower prices. But the GM seeds for which approval is sought are not nicer to eat, safer to use or cheaper to buy. They have been modified to encourage farmers to use other products made by the same companies. Why should a sceptical public support GM when the businesses promoting it are not only the principal beneficiaries but also probably the only ones?
Genetics is the most exciting of today's new technologies and has the potential to revolutionise nutrition and medicine. As with all scientific developments, there is potential for both good and harm. Maximising the benefit requires thoughtful regulation, informed debate and visionary businesses. Instead, we are patronised by a discredited government department, misled by campaign groups that are more interested in publicity than in the truth and let down by companies whose self-interest is so obvious and so short-term that it has proved self-defeating. May biodiversity choke them all.
转基因长出的贪婪
上周，英国政府宣布批准种植一种转基因玉米，但不允许种植类似的转基因油菜或甜菜。据称，这一决定是以环境考虑为依据的：被批准种植的玉米有助于生物多样性，而油菜和甜菜不利于生物多样性。
这里所说的"生物多样性"，只不过是指杂草。因此，所谓的环境损害，与你我用锄头在花床里造成的损害无异。在转基因油菜和甜菜的试验中，杂草得到有效控制。但转基因玉米的试验田比"非转基因玉米"显示出更大的"生物多样性"，也就是说，试验田里生长着并非由农民播种的物种。究其原因，无非是因为种植非转基因玉米的田里，使用了将要受到限制的强力除草剂。
我可不是在开玩笑，虽然我希望是在说笑。这些实验根本不可能产生可靠数据，加深或者缓解公众对于转基因农作物的忧虑。听到这些结果之后，没有任何人有理由改变对转基因农作物的看法，事实上也没有证据表明有谁改变了看法。
这里的背景是，公众对于政府保障食品安全的承诺与能力丧失了信心。这个问题在英国最为严重：有关"疯牛病"和口蹄疫的官方声明，后来都被证明缺乏科学根据和与事实不符。重建信任需要一个缓慢的过程，不可能通过似是而非的实验来实现。从最好的方面说，转基因农作物的试验浪费了大量时间和金钱；从最坏的方面说，这些试验简直是瞎胡闹，让部长们为了眼前的政治利益宣称得到了科学依据。
对于扮演创世主角色创造新的物种，人类普遍感到不安，这是情有可原的。可是，自然界从来不曾存在鲜美多汁的牛排、营养丰富的麦粒、忠实的宠物狗、以及柔情万种的宠物猫。它们是一代又一代选择性繁殖和杂交的产物。杂交玉米新品种的开发(即所谓"绿色革命")，是近50年来对全球扶贫作出最大贡献的因素。说穿了，从农业发明开始，人类就一直在进行基因操作。
通过选择、杂交和转基因，人们既有可能创造出危险及有害的新作物，也有可能创造出更好、食用更安全的作物。企图就转基因对健康和环境的影响作出普遍适用的简单评价是愚蠢的，这就好象质问科学研究是否有益于健康和环境。
如果说政府的政策既自利又愚蠢，反对转基因的团体又何尝不是如此。这些团体大多已经不再具体罗列转基因农作物产生的不良后果(这无疑是明智的，因为此种不良后果的证据并不存在)。更方便的做法(至少是不那么伤脑筋的做法)，是喊口号、践踏种植了转基因农作物的田地，以及表述他们对污染问题(转基因作物的扩散对自然界动植物造成的污染)的关切。但这里的比喻是站不住脚的：转基因是一种技术，不是科学家们掺杂到我们的食品里的添加剂。反对转基因的团体利用公众的无知，在毫无实质依据的情况下掀起莫名的不安情绪。
至于推广转基因的企业，它们的行为可能就更自利和愚蠢了。古往今来，人们接受新技术是因为新技术能提供更好的产品或更低的价格。但申请种植许可的转基因农作物种子，无论在味道、安全性或价位上都不具有优势。之所以要改良基因，是为了鼓励农民们采用由同一公司生产的其他产品。假如推广转基因的企业不仅是主要受益人，而且是惟一的受益人，本来就持怀疑态度的公众还有什么理由要支持转基因呢？
遗传学是当今最扣人心弦的新技术，并有可能在营养和医药领域带来革命性进展。与其他科学开发活动一样，基因科学的潜在用途有好也有坏。要实现其效益的最大化，就需要有周全的法规、理智的辩论，以及富有远见的企业。而现在，我们被一个失信的政府部门鄙视，被对自身形象比对真理更在意的激进团体误导，还被那些自私动机如此显然、如此急功近利以至于自己拆台的企业辜负。但愿有朝一日，"生物多样性"风长，把它们都盖上。
