Traditional biotechnology refers to a number of ancient ways of using living organisms to make new products or modify existing ones. In its broadest definition, traditional biotechnology can be traced back to human's transition from hunter-gatherer to farmer. As farmers, humans collected wild plants and cultivated them and the best yielding strains were selected for growing the following seasons.
As humans discovered more plant varieties and traits or characteristics, they gradually became adept at breeding specific plant varieties over several years and sometimes generations, to obtain desired traits such as disease resistance, better taste and higher yield. With the domestication of animals, ancient farmers applied the same breeding techniques to obtain desired traits among animals over generations.
Centuries ago, people accidentally discovered how to make use of natural processes that occur all the time within living cells. Although they had no scientific explanation for the processes, they applied the results they saw to their domestic lives. They discovered, for example, that food matures in a way that changes its taste and content, and makes it less perishable. Hence, through a process later called fermentation, flour dough becomes leavened in the making of bread, grape juice becomes wine, and milk stored in bags made from camels' stomachs turns into cheese.
Through trial and error and later through advances in technology, people learned to control these processes and make large quantities of biotechnology products. Advances in science enabled the transfer of these mostly domestic techniques into industrial applications and the discovery of new techniques. Examples of traditional biotechnology techniques include selective breeding, hybridization and fermentation.
Modern biotechnology refers to a number of techniques that involve the intentional manipulation of genes, cells and living tissue in a predictable and controlled manner to generate changes in the genetic make-up of an organism or produce new tissue. Examples of these techniques include: recombinant DNA techniques (rDNA or genetic engineering), tissue culture and mutagenesis.
Modern biotechnology began with the 1953 discovery of the structure of deoxyribonucleic acid (DNA) and the way genetic information is passed from generation to generation. This discovery was made possible by the earlier discovery of genes (discrete, independent units that transmit traits from parents to offspring) by Gregor Mendel. These discoveries laid the groundwork for the transition from traditional to modern biotechnology. They made it possible to produce desired changes in an organism through the direct manipulation of its genes in a controlled and less time-consuming fashion in comparison to traditional biotechnology techniques. These discoveries, coupled with advances in technology and science (such as biochemistry and physiology), opened up the possibilities for new applications of biotechnology which were unknown with traditional forms.