NOTES IN BIOTECHNOLOGY
Compiled by: N.R. Bautista
Comparing Traditional and Modern Biotechnology Modern Biotechnology 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 (r DNA or genetic engineering), tissue culture and mutagenesis. Traditional Biotechnology 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 huntergatherer to farmer. As farmers, humans collected wild plants and cultivated them and the best yielding strains were selected for growing the following seasons. Traditional Biotechnology 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 am ong 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 ��������� ������ ��� ����������� �������������
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discovery of new techniques. Examples of traditional biotechnology techniques include selective breeding, hybridization and fermentation. Modern Biotechnology 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. How is Modern Biotechnology Traditional Biotechnology?
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Modern Knowledge
Before the discovery of genes and DNA, genetic changes in organisms (including plants) were carried out at the organism level. For example, a plant with the desirable trait was cross-bred with other plants in the hope that through cross-pollination, the desirable traits would be transferred to the offspring of the parent plants. In modern biotechnology, achieving desired traits in an organism is done mostly at the gene level. Hence, the gene responsible for the desired trait is identified, transferred and inserted into the organism at the cell level, to produce genetic changes. Also, in other modern techniques of biotechnology such as mutagenesis, past knowledge of causes of mutations, known as mutagens, (such as exposure to radiation or temperature extremes) has been harnessed to generate intentional changes in the genetic make-up of a cell or plant tissue. For example, mutation breeding is a biotechnology technique commonly used to develop plants with novel traits. In mutation breeding, plant tissues are exposed to powerful mutagens in hopes of causing beneficial changes in the genetic make-up of the plant cells and then exposed to the conditions under which the plants would have to grow (such as pesticides, limited amounts of water and so forth). Those plants which experienced beneficial mutations survive the exposure to the conditions and are bred and developed into plant lines.
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Applications of Biotechnology
Modern biotechnology has many more applications than traditional biotechnology. Traditional biotechnology focused mainly on food and agriculture through techniques such as selective breeding and fermentation. Science and technology advances have broadened the scope in which biotechnology can be applied to include the environment (bioremediation and bio-filtration), human and animal health (development of vaccines and drugs, gene therapy, diagnostics), energy (production of bio-fuels), forestry (production of bio-pesticides and genetically modified tree seedlings) and other areas. Techniques of Biotechnology
Advances in science and technology have led to the development of new types of biotechnology techniques that did not exist in traditional biotechnology. For instance, modern biotechnology includes such techniques as recombinant DNA techniques (also known as genetic engineering), mutagenesis breeding, hybridoma technology and tissue culture. Most of the techniques used in modern biotechnology have been developed as a result of the increased knowledge of genetics and microorganisms. For example, in the traditional biotechnology technique of selective breeding, only plants that were similar (of the same species) were cross-bred. However, through recombinant DNA technology in modern biotechnology, genes can be transferred between unrelated species, for example between bacteria and humans. Therefore, modern techniques of biotechnology have widened the gene pool from which genes with desired traits can be obtained for transfer into organisms lacking those traits. Also, modern techniques such as recombinant DNA techniques and mutagenesis have made it possible to develop novel products in larger amounts than was possible in traditional biotechnology. For instance, in rDNA technology, genes with useful (desirable) traits from plants and animals are transferred into microorganisms, such as yeasts and bacteria, that are easy to grow in large quantities. This technique is used in producing genetically modified bacteria to produce humulin, human insulin used to treat diabetes. Since the discovery of insulin in 1921, humans have relied on the use of animal insulin to treat human diabetes. However, some diabetic patients have had adverse reactions to it. There was also concern about the possible decline in the production of animal-derived insulin. Hence, researchers formulated a way of synthesizing humulin by inserting the insulin gene into bacterial cells to produce insulin that is chemically identical to its natural counterpart. The right form of insulin can now be obtained in much larger quantities than before. Time and Precision
The discovery of the structure of the DNA molecule and the way genetic information is passed from generation to generation has made the transfer of genes and therefore desired traits between organisms using modern biotechnology more precise and less time consuming than traditional biotechnology. Although it is not guaranteed that every cell used in the process incorporates the transferred gene, the probability of cells incorporating the ��������� ������ ��� ����������� �������������
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desired gene is much higher using modern biotechnology techniques than with traditional biotechnology. In addition, using traditional techniques it took many generations and was a lot more time consuming to produce plants and animals with desired traits, since those techniques were mostly based on trial and error. Knowledge of the actual genes being transferred, coupled with modern technology, has significantly reduced the time it takes to obtain the same results in traditional biotechnology. Bibliography Biotechnology in Agriculture. {www.probiotech.fsnet.co.uk/index.htm} Myths and Facts About Food Biotechnology. {www.ificinfo.health.org/foodbiotech/mythsfacts.htm} Australian Biotechnology Association: Biotechnology in animal agriculture - No. 4. {www.aba.asn.au/pages/leaf4.htm} Access Excellence: About Biotech - Overview and Brief History. {www.accessexcellence.org/AB/BC/Overview_and_Brief_History.html} A Glimpse of Biotechnology: Food without the "Birds and the bees." {www.probiotech.fsnet.co.uk/index.htm} Biotechnology Background. {www.american.edu/projects/mandala/TED/SOYBEAN.HTM} Australian Biotechnology Association: Biotechnology in plant agriculture - more or less. No. 3. {www.aba.asn.au/pages/leaf3.html} Defining Modern Biotechnology With Beer, Bread and Cheese? BIOFUTURES March16, 2000, Naomi Sunderland. {www.brisinst.org.au/resources/Naomi_biodef.html} Biotechnology - EUFIC reviews and brochures: The Origins of food biotechnology {www.eufic.org/gb/tech/pag/tech01a.htm} Northern California Biotechnology Center: What is Biotechnology? {www.smcccd.cc.ca.us/smcccd/skyline/NCBC/aboutbiotech.html}
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