At almost every public lecture I give, someone asks me my opinion on genetic modification—whatever be the topic of the lecture. Genetic modification (GM) has the power to save lives through its use in medicine, such as the production of insulin for diabetics or the treatment of genetic disorders. The current outcry comes when it is used to produce food.
Some of these public concerns reflect real problems, but others are fuelled by misinformation and overdramatisation.
There is nothing new about crop modification; plant breeders have been doing it since agriculture began. The wonderful range of apples or potatoes we now enjoy is the result of crossing different varieties. Cabbages, Brussels sprouts, cauliflower, kohlrabi, kale and broccoli all originated from one botanical species.
Modern molecular biology has enabled us to go much further. We can now isolate the gene for a particular characteristic of an organism and transfer it to another species. It is this practice of transforming a plant with alien genes—perhaps from an animal or bacterium—that is causing all the controversy.
There are three main concerns.
Scientists can now take a gene for resistance to a particular herbicide and transfer it to a crop: when these plants are sprayed with weed-killer, the weeds are destroyed while the crop is unharmed. A prime concern is the harmful effect this could have on the biodiversity of farmland, where so many insects, birds and other animals depend upon “weed” species.
Another fear is that alien genes from a GM plant could escape into a wild population of a related species. Since plants are fertilized by pollen that is carried through their, often for great distances, this is entirely possible. A wild species modified in this way with pesticide resistance could become a “super-weed”, while a species that becomes unnaturally resistant to animals that feed on it could disrupt the food chain.
The third worry concerns a proposal to produce seeds for cereals that cannot germinate to produce next year’s seeds. This “terminator technology” would be of obvious advantage to seed companies, since farms would be forced to buy new weed annually.
But the same technology could be devastating to some farmers in the developing world who depend upon saving some seeds for next year’s crop. Fortunately this technology is not yet in use and there has been strong pressure to abandon it.
I would not hesitate to eat a GM vegetable—it is most unlikely that the current modifications are harmful to the consumer, despite what we read in the press. However, the introduction of animal genes into food plants presents considerable ethical difficulties to vegetarinsarians and member of religious that forbid the eating of certain animals.
This is one of the reasons people are demanding that tall genetically modified food products be clearly labeled. The public have a fight to know what they are eating and a fight to choose.
I believe that in my own nation GM is well regulated, but this cannot be said for some other countries. One of the problems is that at the moment this technology is commercially motivated. Because the compositions developing GM food want to introduce it as quickly as possible, in my opinion, it is being rushed into without adequate research or precautions.
Genetic’ modification is here to stay, and there is no doubt it will save lives. But, like so many other scientific discoveries, such as splitting the atom, it can be seriously misused. Instead of condemning the technique, we, should ensure it is used wisely. We need to evaluate each application carefully, from environmental and ethical standpoints, and we must urge governments and companies to use it for good rather than for greed.

【正确答案】

几乎每次公开演讲时,无论演讲题目是什么,都会有人问我对转基因技术的态度。“转基因”功能强大:运用在医药上,它可以拯救生命。例如,制造治疗糖尿病的胰岛素,以及治疗基因紊乱。但是日前,在我们打算将转基因技术应用于食品生产时,却遭到了一些人的强烈反对。
公众的担忧反映出许多现实存在的问题,但也有些强烈的不满是由于错误的信息和过分渲染而造成的。
农作物的转化已不是新鲜事,有史以来,农民们就已经一直在进行着嫁接。我们现在食用的各种苹果和马铃薯就是不同种类的交叉品。卷心菜、汤菜、花椰菜、芥蓝、甘蓝、西兰花在植物学中都属于同一物种。
现代分子生物学使得我们更进一步。如今,我们可以把某一生物的独特基因分离出来,转移到另一物种中去。而正是这个通过植入外来基因——可能是动物或细菌的基因,来改变植物的做法引起了普遍争议。
人们的担心主要来自以下三个方面。
科学家们可以取一种抵抗除草剂的基因移植到农作物中去。当洒上除草剂时,杂草被杀死,而农作物可以不受损害。令人担心的是,这样做会损害到庄稼地里物种的多样性——因为许多昆虫,鸟类及其他动物是以这些“杂草”为生的。
另一个担心是,转基因农作物中的外来基因可以形成许多相关物种。由于植物是由空气传播花粉来繁殖的,花粉在长距离的飞行过程中就可能引起新物种的生成。当一个野生品种被这种含有抗杀虫剂的外来基因转变时,就有可能会成为“超级野草”。如果一个物种具有抵抗以它为食的动物的能力,就违反了自然法则,也会破坏食物链。
第三点令人担忧的是有可能为下一年无法繁殖的谷物制造种子。此项“终结者技术”当然对种子公司大有好处,这样农民们就被迫得每年买种子。
但是同样的技术对发展中国家的某些农民来说却是灾难性的。他们每年都需要储存庄稼的种子以备来年耕种。幸好这项技术还没有应用到实践中,它面临着来自反对者的巨大的压力。
我会毫不犹豫地食用转基因蔬菜。不管报纸杂志怎么说,现代的基因转换都不大可能伤害消费者。然而,在素食主义者和那些因为信仰而禁食某些动物的宗教人士看来,把动物基因引入到食用植物的做法存在很大的伦理问题。
这也是人们为何要求清楚地标明所有转基因食品的原因之一。公众有权知道他们吃的什么,他们有权选择吃还是不吃。
我相信在我们国家,转基因食品已经受到了严格的规范,但是其他国家并不一定如此。问题之一是,当今这项技术是以商业利益为动机的。因为商家们要尽可能快地开发转基因食品,依我看,这项技术在没有进行充分研究和采取预防措施的情况下发展得过快。
转基因将继续存在,无疑它还能拯救生命。但是正如分裂原子等许多其他的科学发现一样,它也可能被过度滥用。我们不该谴责技术本身,而是应该确保其被明智地利用。我们需要从环境和伦理角度来对每项应用进行仔细评估。我们必须督促政府及商家确保人们从中受益,而不是为了满足他们的贪心。

【答案解析】