History of biotechnology

If we define biotechnology as the application of science or technology to biological systems, as many do, then biotech started 10 000 years ago, when humans first decided to put down roots and modify their surroundings to meet their needs rather than chase the desired environment with the seasons, geography and so on. Human society has manipulated and altered living systems (i.e. applied biotechnology) ever since—particularly in the pursuit of food. Intentional selection of preferred seeds for planting, rather than for consumption, was an early manifestation of biotechnology. Even this early form of agricultural biotechnology left an unexpected human footprint: planting selected seeds meant displacing whatever species were occupying that land before. As humans expanded their number and reach, the influential human footprint grew bigger and broader. Agriculture now constitutes the greatest human impact on Earth, covering over 5 billion hectares of the 13 billion hectares of land available (see www.fao.org). That is 5 billion hectares of displaced or eliminated species, usually replaced with species and genotypes unknown to the Earth of 10 000 years ago.

The term biotechnology can also be applied to many traditional and modern forms of food processing: making bread by combining yeast with crushed wheat, wine from grape squeeze and microbes, beer from hops, barley and yeast. These forms of food production using fermentation technology require human intervention and manipulation of nature to yield the food products most humans have enjoyed for millennia. Almost all other foods and food processes have been altered, modified, or improved by humans over history

(see, for example, McGee, 1984). Today, apart from a few wild berries, some aquatic species that manage to survive overfishing, and some game animals that manage to survive increasingly techno-accelerated hunters, almost none of our common foods can be said to be genetically unmodified by humans (McHughen, 2000).

More modern forms of plant breeding and animal husbandry have generated genetically modified forms of crop varieties and animal breeds. These novel beasts and plants carry traits suited to human cultivation and consumption, not to fitness and survival in the wilderness, as Nature would have. And it is true that human meddling in the genes of plants and animals, even using "natural" means of genetic modification, can and does lead to unintended effects, even mistakes requiring postmarket eradication (NAS, 2004).

In modern parlance, biotechnology generally refers to modern genetic technologies, particularly recombinant DNA (rDNA), also known as genetic engineering. To gain a basic understanding of genetic engineering, one must understand the four basic concepts that serve as the foundation of genetics:

1. All organisms are made of cells and cell products

2. Each cell in an organism contains the same set of genes

3. The genome contains all the genetic information necessary to make an entire organism

4. All organisms share the same genetic language.

These four concepts encompass our knowledge of molecular and cellular genetics dating from the early twentieth century to the 1960s. For genetic engineering, the key is concept number 4. The fact that all organisms share the same genetic language allows a gene from any one organism or species to be read and understood when transferred to any other.

By analogy, consider a gene to be a recipe, and the genome to be the comprehensive encyclopedia of recipes, comprising all of the genetic information in a given organism. There may be 20 000-30 000 genes in the genome of a plant or animal, including humans. Each gene conceptually codes for a particular protein. When a gene consisting of the coded recipe for, say, the protein insulin is copied from the human genome and transferred to bacteria (which ordinarily lack the insulin gene), the bacteria acquire the ability to synthesize human insulin.

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