RECOMBINANT DNA TECHNOLOGY AND ITS APPLICATION
25 likes20,255 views
Recombinant DNA technology has had widespread global impacts. It has applications in medicine like producing insulin, vaccines, and cancer treatments. In agriculture, it has led to herbicide and insect resistant crops as well as efforts to engineer nitrogen-fixing plants. It also has uses in animal husbandry such as producing transgenic animals. Additional applications include DNA fingerprinting for forensics, producing monoclonal antibodies, and developing diagnostic tests and gene therapies. While offering benefits, it also raises ethical issues that require ongoing research and regulation.
RECOMBINANT DNA TECHNOLOGY AND ITS APPLICATION
- 1. GLOBAL IMPACTS OF RECOMBINANT DNA TECHOLOGY GLOBAL IMPACTS OF RECOMBINANT DNA TECHNOLOGY. GIKONYO NDICHU STANLEY. I23/4609/2013. SCHOOL OF BIOLOGICAL SCIENCES. UNIVERSITY OF NAIROBI.
- 2. GLOBAL IMPACTS OF RECOMBINANT DNA TECHOLOGY ABSTRACT In the recent years, about six decades ago, the urge to learn and unravel the mystical question, “What drives life” has increased dramatically. This has led to deep coverage of the morphology of living things from the smallest living bacteria, viral particles to the largest living creatures. The motivating factors have been to curb some human life complications, for example diseases and to increase the understanding of life. This has led to major discovery achievements of the basic unit of life, the cell, and its inner depth of diversity. The discovery in 1953 of the double-stranded, complimentary structure of DNA provided a kind of a rough structure to emerging field of molecular genetics. The elegantly simple structure furnished a model for the designs of experiment which, in tree intervening decades, have led to our current understanding of the genetic code, the biochemical mechanism of the translation of genetic information, and the ways in which genes are regulated. As molecular geneticists directed their efforts from the general properties of DNA to the structure and properties of individual gene, however, they began to encounter tremendous experimental difficulties. The low cellular concentration of genes, the complexity of their nucleotide sequences, and the complexity of the genome into which they are organized organised loomed as possibly insurmountable barriers to the further biochemical study of gene structure and function. The methods known collectively as recombinant DNA techniques (rDNA technology) evolved in this tradition of study gene structure through microbial genetics and the DNA biochemistry. In 1990, the National Institutes of Health (NIH) and the Department of Energy joined with international partners in a quest to sequence all 3 billion letters, or base pairs, in the human genome, which is the complete set of DNA in the human body. This concerted, public effort was the Human Genome Project. The Human Genome Project’s goal was to provide researchers with powerful tools to understand the genetic factors in human disease, paving the way for new strategies for their diagnosis, treatment and prevention and other numerous application. In April 2003, researchers successfully completed the Human Genome Project, under budget and more than two years ahead of schedule. This eased the previous problems encountered by the researches since genomes of many organisms were availed freely for simpler study. Since then the rDNA technology has been enhances in many fields of application. Recombinant DNA technology is one of the most fascinating fields of biotechnology with its numerous applications making many positive impacts worldwide. It has invaded many field, for example, medicine, and it is becoming one of the best solutions to some disturbing problems, for example, genetic diseases like cancer, however, some questions arise about its side effects, for instance, the GM food and organisms, but with continued research it is being perfected to make life of earth better. This technique can be best described as the transfer of a sequence of DNA (gene) from one organism to another. Hence, it is also referred to as “molecular cloning” or “gene cloning” or broadly as “genetic engineering”. This paper will view its application in various
- 3. GLOBAL IMPACTS OF RECOMBINANT DNA TECHOLOGY fields and how it has impacted our world including the social and economic aspects in some applications. Medicine Genetic engineering has resulted in a series of medical products. The first two commercially prepared products from recombinant DNA technology were insulin and human growth hormone, both of which were cultured in the E. coli bacteria. Since then a plethora of products have appeared on the market, including the following abbreviated list, all made in E. coli (a bacteria): A vaccine is usually a harmless version of a bacterium or virus that is injected into an organism to activate the immune system to attack and destroy similar substances in the future. Tumour necrosis factor. Treatment for certain tumour cells Interleukin-2 (IL-2). Cancer treatment, immune deficiency, and HIV infection treatment Prourokinase. Treatment for heart attacks Taxol. Treatment for ovarian cancer Interferon. Treatment for cancer and viral infections In addition, a number of vaccines are now commercially prepared from recombinant hosts. At one time vaccines were made by denaturing the disease and then injecting it into humans with the hope that it would activate their immune system to fight future intrusions by that invader. Unfortunately, the patient sometimes still ended up with the disease. With rDNA technology, only the identifiable outside shell of the microorganism is needed, copied, and injected into a harmless host to create the vaccine. This method is likely to be much safer because the actual disease-causing microbe is not transferred to the host. The immune system is activated by specific proteins on the surface of the microorganism. rDNA technology takes that into account and only utilizes identifying surface features for the vaccine. Currently vaccines for the hepatitis B virus, herpes type 2 viruses, and malaria are in development for trial use in the near future. Agriculture Crop plants have been and continue to be the focus of biotechnology as efforts are made to improve yield and profitability by improving crop resistance to insects and certain herbicides and delaying ripening (for better transport and spoilage resistance). The creation of a transgenic plant (genetically modified), one that has received genes from another organism, proved more difficult than animals. Unlike animals, finding a vector for plants proved to be difficult until the isolation of the Ti plasmid (a bacteria organelle), harvested from a tumour-inducing (Ti) bacteria found in the soil. The plasmid is “shot” into a cell, where the plasmid readily attaches to the plant's DNA. Although successful in fruits and vegetables, the Ti plasmid has generated limited success in grain crops. Creating a crop that is resistant to a specific herbicide proved to be a success because the herbicide eliminated weed competition from the crop plant. Researchers discovered herbicide-resistant bacteria, isolated the genes responsible for the condition, and “shot” them into a crop plant, which then proved to be resistant to that herbicide. Similarly, insect-resistant plants are becoming available as researchers discover bacterial enzymes that destroy or immobilize unwanted herbivores, and others that increase nitrogen fixation in the soil for use by plants. Geneticists are on the threshold of a major agricultural breakthrough. All plants need nitrogen to grow. In fact, nitrogen is one of the three most important nutrients a plant requires.
- 4. GLOBAL IMPACTS OF RECOMBINANT DNA TECHOLOGY Although the atmosphere is approximately 78% nitrogen, it is in a form that is unusable to plants. However, a naturally occurring rhizobium bacterium is found in the soil and converts atmospheric nitrogen into a form usable by plants. These nitrogen-fixing bacteria are also found naturally occurring in the legumes of certain plants such as soybeans and peanuts. Because they contain these unusual bacteria, they can grow in nitrogen-deficient soil that prohibits the growth of other crop plants. Researchers hope that by isolating these bacteria, they can identify the DNA segment that codes for nitrogen fixation, remove the segment, and insert it into the DNA of a profitable cash crop! In so doing, the new transgenic crop plants could live in new fringe territories, which are areas normally not suitable for their growth, and grow in current locations without the addition of costly fertilizers! Animal Husbandry Neither the use of animal vaccines nor adding bovine growth hormones to cows to dramatically increase milk production can match the real excitement in animal husbandry: transgenic animals and clones. Transgenic animals model advancements in DNA technology in their development. The mechanism for creating one can be described in three steps: 1. Healthy egg cells are removed from a female of the host animal and fertilized in the laboratory. 2. The desired gene from another species is identified, isolated, and cloned. 3. The cloned genes are injected directly into the eggs, which are then surgically implanted in the host female, where the embryo undergoes a normal development process. It is hoped that this process will provide a cheap and rapid means of generating desired enzymes, other proteins, and increased production of meat, wool, and other animal products through common, natural functions. Ever since 1997 when Dolly was cloned, research and experimentation to clone useful livestock has continued unceasingly. The attractiveness of cloning is the knowledge that the offspring will be genetically identical to the parent as in asexual reproduction. DNA Finger Printing The technique of DNA fingerprinting was developed and established by British geneticist Dr. Alec Jeffreys. Every individual organism is unique in its finger prints. Similarly every individual differs from other in his DNA pattern or design. Finger prints can be altered by surgery but there is no known procedure available to alter the DNA design of an individual. For obtaining the DNA finger prints of an individual, one should look for genes that are highly polymorphic or occur in multiple forms in different individuals. (In other words, genes which are multi allelic in a population) This technique can be applied in various fields such as: (i) In forensic Science to identify the criminals. (ii) To establish the parentage of a child i.e. to establish the biological father or mother of a child in case of a dispute. (iii) To identify an ethnic group or to deduce the evolution of a racial group. Molecular biology: This technique is used to elucidate molecular events in biological processes like cell differentiation, aging and gene mapping etc. Recombinant DNA technology is used in various ways to diagnose diseases. One way of diagnosis is to involve the construction of probes (short single strand DNA or RNA) with radioactive fluorescent marker. These probes are used to test the DXA of prospective genetic disorder carrier parents.
- 5. GLOBAL IMPACTS OF RECOMBINANT DNA TECHOLOGY Their chances of producing afflicted child can be predicted. Such probes are also routinely used for identification of infectious agents, for instance, food poisoning Salmonella, pus forming Staphylococcus, hepatitis virus, IIIV etc. Another way is the production of monoclonal antibodies or MAB Monoclonal antibodies Antibodies are specific proteins produced by the immune system in response to presence of a specific antigen. Monoclonal antibodies can be produced using hybridoma technology. Hybridoma technology is used to fuse a normal antibody producing lymphocytes (B-cells or plasma cells) with myelonema cells (a kind of tumour cells) giving a hybridoma. Hybridoma has the potential to grow indefinitely in culture and hence can be a source of unending supply of antibody of choice. Since antibody produced by a hybridoma is biochemically pure, it is called monoclonal antibody. Monoclonal antibodies are used to develop effective vaccines against human, animal and plant diseases. Diagnosis of infection disease. Modern medical practice depends on laboratory tests for the specific and correct diagnosis of many diseases. Recombinant DNA technology allows for the production of highly specific diagnosis tests. Some of the common infectious diseases are cholera, small pox, measles meningitis, hepatitis, etc. These diseases lead the serious damage to the human health. Infectious diseases diagnosis mainly depends upon isolation and identification of pathogens, which may take several days. Development of diagnostic kits to identify pathogenic organisms by knowing the organism-specific DNA sequence has provided rapid, specific and correct diagnosis. In this way, advancement in biotechnology has made easy early, correct and quick diagnosis of infectious diseases. Various diagnostic kits have been developed for AIDS, cancer, foot and mouth diseases, tuberculosis, etc. Different biotechnological tools used in diagnosis of infectious diseases biotechnology tools used in diagnosis of infectious diseases and prenatal diseases are ELISA (enzyme-linked immunosorbent assay), PCR (polymerised chain reaction) based technique, RIA (radioimmunoassay) Essays, etc. Gene Therapy Gene therapy in humans is another possible use of rDNA technology. In this process, the gene is added to a virus and then inserted into human cells. Because viruses link up with the DNA strands of the host, the new gene is therefore expressed in the person. (In this type of therapy, the virus has been modified so it does not cause disease.) In cancer patients, genes can be inserted to correct abnormal genes, to introduce a "suicide gene" into the cancer cells or to increase the patient's immunity. It is useful to couples before marriage to know if some partners have defective genes and how they can be corrected to avoid having offspring inherit some unsuitable characteristic. In-Utero Gene Therapy Another way that rDNA technology can be used is in gene therapy on a foetus. The advantage to using gene therapy in utero is that the foetus has a much higher stem cell count, making it easier to correct genetic abnormalities, such as cystic fibrosis. It may also be used in cases where the foetus is not making a certain protein or enzyme. In-utero gene therapy is done by injecting a virus with the new DNA into the amniotic fluid, which the foetus then takes in by breathing. Conclusion. The applications of rDNA technology are limitless with new ones arising from the continued molecular biology. It is used in nearly all field, some of which are medicine,
- 6. GLOBAL IMPACTS OF RECOMBINANT DNA TECHOLOGY industries, pharmaceutical, agriculture, diagnostics and forensic science among many. It has cheapened life by making disease treatment, food production and production in industries easier. By making some diseases curable and improving conditions of those living with diseases such as AIDS better, social life in the society and the world at large is enhances. Animal and human protection against diseases and plant protection against pest and diseases achieved through these techniques makes life better and promotes harmony among living things. Although rDNA technology provides many benefits and advantages, several ethical considerations and controversies are associated with this technology. Many people believe that altering human DNA is immoral and constitutes "playing God." In addition, because this is a fairly new technology, there are questions about the long-term health effects of consuming genetically altered plants and animals. Some of this concerned are promised to be solved by continued research and well utilization of the knowledge by scientist. The use and application of rDNA technology is regulated by global organizations such as Environmental Protection agency (EPA), Food and Drug Administration (FDA) and Office of Science and Technology (OSTP) which ensure that the knowledge is used for the correct and safe purposes. References. S. Mahesh, A.B. Vedamurthy. (2004). Biotechnology-4 Including Recombinant DNA Technology, Environmental Biotechnology and Animal Cell Culture. New Delhi: New Age International Publishers. Q. Ashton Acton. (2013). Advances in Biotechnology Research and Application. Atlanta, Georgia: ScholarlyEditions. O.S. Reddi. (2000). Recombinant DNA Technology, A Laboratory Manual. Mumbai: Allied Publishers Limited. Maureen Malone. (2013). Application of Recombinant DNA Technology. Retrieved from eHow website: http://www.ehow.com/print/about_6165534_application-recombinant-dna-technology.html