Molecular Biotechnology In Life If you have had a can of soft drink, ate a fruit, or took some head ache medicine this morning - then it's very likely you have used a genetically enhanced product. Genetics is a part of biotechnology that manipulates biological organisms to make products that benefit humankind. Biotechnology is essential in our life, but there are some concerns regarding its safety. Although, biotechnology may pose some danger it is proving to be very beneficial to humankind. The first applications of biotechnology occurred approximately around 5000 BC. Back then people used simple breeding methods.
Chains of plants or animals were crossed to produce greater genetic variety. The hybridized offspring then were selectively bred to produce the desired traits. For example, for about 7000 years, corn has been selectively bred for increased kernel size and additional nutrition value. Also, through selective breeding, cattle and pigs have become the major sources of animal foods for human (Encarta 99). The modern era of biotechnology started in 1953 when British biophysicist Francis Crick and American biochemist James Watson presented their double-stranded model of DNA.
DNA is an extensive, chain-like structure made up of nucleotides, and in a way it looks like a twisted rope ladder (Drlica 27). In 1960 Swiss microbiologist Werner Arber had discovered restriction enzymes. This special kind of enzymes can cut DNA of an organism at precise points. In 1973 American scientists Stanley Cohen and Herbert Boyer removed a specific gene from one bacterium and inserted it into another using restriction enzymes. This achievement served as foundation to recombinant DNA technology, which is commonly called genetic engineering.
Recombinant DNA technology is a transfer of a specifically coded gene of one organism into bacteria. Further, the host bacteria serve as a biologic factory by reproducing the transferred gene. Today biotechnology's applications are used in a variety of areas. It's used in waste management for creation of biodegradable materials, in agriculture for higher yields and quality, in medicine for production of advanced pharmaceuticals, cloning tissues and curing genetic diseases. However there is a down side to genetic engineering.
It deals with dangerous bacteria which could escape the boundaries of a lab and possibly cause epidemics. Moreover, if a transgenic organism escapes, it could eliminate a range of species and thus disrupt natural balance. Since biotechnology is a necessity, some government guidelines were established for strict regulation of recombinant DNA experiments (Encarta 99). Agriculture is the largest business in the world, with assets of approximately $900 billion and about 15 million employees. Back in the 80's, there was a concern, based on population growth rates, that by the turn of the century traditional agriculture would be in a serious trouble (Hanson 68). But due to the revolutionary development of biotechnology during last couple of decades agriculture has drastically advanced.
Sensational achievements were made in both plant cultivation and animal husbandry. The modification of plants has become one of the most important aspects in agriculture. Increased crop yields can be achieved through the increase of land, or increased yield per tract. Land is expensive and should be used efficiently, to do so - large quantities of fertilizer, herbicides, pesticides and frequent irrigation may be necessary. Due to the increase in petroleum cost - prices for nitrogen fertilizers continuously rise.
Herbicides and pesticides are considered to be hazardous and very costly materials. Moreover, recurrent irrigation gradually leads to serious damage of the soil due to the salt accumulation. Eventually, increased amounts of salt in the soil result in large losses of crops (Hanson 69). Biotechnology can incorporate genes that are resistant to environmental stress, viruses, and insects. Such modified plants will be resistant to the same factors as the incorporated gene.
Crop plants could be genetically engineered to manufacture functional insecticides so that they are immanently tolerant to insects. No hazardous and costly pesticides are needed for such plants resulting in very low crop maintenance costs. Moreover, biological insecticides are highly specific for a range of insects and considered to be harmless to humans and other higher animals (Glick and Pasternak 341). Plant viruses very often attack crops and cause significant damage and loss of crops. Recombinant DNA technology offers a few ways to obtain natural virus resistance: viral transmission can be blocked, development of the virus can be blocked, or viral symptoms can be bypassed or resisted (Glick and Pasternak 345). Biotechnology also contributes to the development of plants with higher tolerance to environmental changes.
Plants cannot avoid hazardous environmental conditions such as heat, drought, and UV radiation, so they have developed physiological ways to deal with those stresses. One of the undesirable effects of physiological stress is production of oxygen radicals. Trough the use of recombinant DNA technology some plants are given the ability to tolerate high levels of oxygen radicals, these plants are capable of withstanding a various range of environmental stress (Glick and Pasternak 350). Another important area of biotechnology is improvement of livestock. Many generations of selective matings are required to improve livestock and other domesticated animals genetically for traits such as milk yield, wool characteristics, rate of weight gain, and egg laying frequency. At each successive generation, animals with superior performance characteristics are used as breeding stock.
Eventually, high production animals are developed as more or less pure breeding lines. This combination of mating and selection, although time-consuming and costly, has been exceptionally successful. Today almost all aspects of the biological basis of livestock production can be attributed to this process. However, once an effective genetic line has been established, it becomes difficult to introduce new genetic traits by selective breeding methods (Glick and Pasternak 359). Until recently, the only way to enhance genetic properties of domesticated animals was selective breeding. However, research in new areas of biotechnology lead to the development of new technologies and almost completely replaced traditional methodologies.
Using recombinant DNA technology, scientists are able to insert a specific cloned gene in to the nucleus of fertilized egg of a higher organism. Then the fertilized egg is implanted into a receptive female. Most of the offspring derived from the implanted eggs will have the cloned gene in all their cells. The animals with the transgenic gene in their germ line are bred to establish new superior genetic lines. For example if the injected gene stimulates growth, the animals that received the gene would grow faster and require less food.
Even if consumption of food was cut down by only a few percent - it still would have a profound effect on lowering the cost of production and the price of final product (Glick and Pasternak 361). Another area that benefits from biotechnology is medicine. This particular sector of biotechnology had risen from about $6 billion share of global market in 1983 (Hanson 66) to about $100 billion in 1997 ("The Biotech Boom" 89). McDonald states that "today, there are more than 2,200 drugs that are in development and 234 awaiting approval from FDA" (91). The primary reasons for such rapid development are millions of deaths each year caused by disease, viruses, and ...