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close this bookBiotechnology and the Future of World Agriculture (GRAIN, 1991)
close this folderThe tools
View the document(introduction...)
View the documentCutting and pasting
View the documentAbout language and limitations
View the documentCulturing cells and tissues
View the documentControlling the process
View the documentA new threshold?

About language and limitations

The US biotechnology company Genex, in its 1982 annual report, used an interesting analogy to explain what genetic engineering is all about:

DNA can be thought of as a language, the language in which all nature's genetic information is written. As with any language, it is desirable to be able to read, write and edit the language of DNA. Rapid methods for determining the substructure of DNA, developed a half a dozen years ago, correspond to reading DNA. These methods now make it possible to determine the complete structure of a gene in a few weeks. New and still rapidly evolving methodologies for chemical synthesis of DNA molecules make it possible to write in the language of DNA much more rapidly than was possible only a couple of years ago. Finally, and most important, genetic engineering techniques themselves make it possible to edit the language of DNA. It is by this editing process that the naturally occurring text can be rearranged for the benefit of the experimenter. (3)


Time needed for the synthesis of a gene

The biotechnologist as a desk-top publisher - the comparison is an intriguing one. As electronic desk-top publishing made giant leaps forward when computers and software became available, the cutting and pasting of the hereditary material became possible with molecular techniques to read and gene-machines to write DNA sequences. Graph 3.1 shows how fast the technology has developed. In the late 1970s, the synthesizing of a simple gene could take several months, a process which, through automation, is being rapidly standardized. But the desk-top publishing analogy also serves to show the tremendous difficulties still faced by genetic engineers. Ever sat in front of a computer, staring at the message 'disk error, please exit!', thus losing several hours of work? The average word-processor user, like myself, has little understanding of exactly how a computer and its software do its work. You type letters on the keyboard and they appear on the screen. The level of understanding that the biotechnologist has of living organisms is similar. Genetic material can be read, written and edited, but the understanding of how and why genes express themselves, how they really function in a living being and what is their precise role in the overall picture, is largely a mystery.

In part the question is simply to refine the technology, further to deepen the understanding of genetics. But the problem also lies with the limited focus of molecular biology itself. A quote from Edward Yoxens's excellent though by now somewhat outdated book, The Gene Business, might be appropriate:

For molecular biologists, life is what genes do. For them genes are the key to life, and one need look no further than this for the central problems of biology. In their hands biology has become a kind of flatland in which the only activity is the processing and transmission of genetic information . . . I prefer to think of molecular biology as the expression of a Meccano view of nature. With a fairly simple conceptual kit and with a limited number of elements, molecular biologists have been able to represent living nature with a series of increasingly complex mechanical models. They have spent years figuring out what pieces there are in nature's Meccano set, and how they fit together. Some of the more theoretically inclined have examined the very principles of construction, the rules of order and geometry built into the Meccano parts. And now, finally, since the early 1970s they have figured out how to start bolting pieces together, making new models that are not even in the instruction books. (4)

While discussing biotechnology it is tempting to focus predominantly on genetic engineering - recombinant DNA technology - as being the most challenging and dramatic. It is, however, important to stress that recombinant DNA technology is only one of the instruments in the biotechnology tool kit. Biotechnology is a very broad term, for which many different definitions have been given. One widely used description of biotechnology includes 'any technique that uses living organisms (or parts of organisms) to make or modify products, to improve plants and animals, or to develop micro-organisms for specific uses'. (5) This, indeed, includes the whole spectrum of new and old biotechnologies from simple plant-breeding to high-tech gene transfer. Generally referred to as the new biotechnologies, are the basic techniques that have been developed and/or perfected in the past two or three decades. Apart from recombinant DNA techniques, they include tissue culture, cell fusion, enzyme and fermentation technology and embryo transfer. None of them make much sense on their own. It is the integrated use of all these different technologies that make the new biotechnologies so powerful and commercially interesting.


Table 3.1 Milestones in biotechnology