Genetic Engineering and DNA Effects - Research Paper Example

Genetic Engineering and DNA Effects Genetic engineering refers to the collection of techniques employed inthe identification, replication, modification and transfer of genetic materials in the tissues and cells of living organisms so as to produce new substances or perform new functions. These techniques came into use for the first time in the 1950s with the discovery of the structure of Deoxyribonucleic Acid, DNA molecules by Francis Crick and James Watson. Genetic engineering occurs in the DNA, the blueprint constituting genes, known for transmitting genetic information in living organisms. This paper evaluates various secondary sources to qualitatively analyze the nature of DNA functioning and how genetic engineering affects it and its operations. With the much debate on ethical issues with regard to genetic engineering, the advantages and disadvantages, together with the social and ethical concerns elicited by the technology would also be evaluated. Indeed, in spite of the ethical implications that arise from practice, genetic engineering plays a vital role in medical science and ensuring positive health outcomes in humans. Introduction Deoxyribonucleic acid, DNA occurs in every living organism and would be specifically located in the nuclei of cells that make up the body. As such, DNA could be considered as among the components making up a body. DNA has a double helix structure with a pair of twisted parallel strands between which would be spotted rungs resembling a ladder. The strands of DNA would be packed in the nuclei to form chromosomes, visible during cell division. In humans, there are 23 pairs of chromosomes, 22 of which pairs resemble in both females and males, referred to as autosomes. The different pair between females and males refers to the sex chromosomes with females and male having XX and XY chromosomes respectively (Starr & McMillan, 2012). DNA, also referred to as the blueprint makes up genes which instruct the formation of protein molecules. Thus, basically, the DNA refers to the hereditary material in the human and other living organisms’ cells. However, Fry (2011) notes that DNA could also occur in the mitochondria, referred to as mitochondrial DNA, mtDNA. The components of DNA found in each strand include Adenine (A), Guanine (G), Cytosine (C) and Thymine (T). These bases repeat in arrays of sequence in the DNA molecule forming genes. The coupling together of these base chemicals form linkages referred to as base pairs responsible for holding together the pairs of spirals making up each DNA molecule and instruct on the development of cells and the tasks to be undertaken. Each base would be attached to a phosphate or sugar molecule (Fry, 2011). The entire genetic sequence of an organism is referred to as genome and would have DNA base pairs in their billions (Starr & McMillan, 2012). Nonetheless, genetic engineering does not involve such individual base pairs but rather larger DNA segments referred to as genes. It rides on the discovery of DNA as transmitters of genetic information. Humans have about 3 billion DNA bases which would occur in varied sequences based on the information to be transmitted. To illustrate this, an example cited by Resnik and Vorhaus (2006) would be considered. Supposing the DNA molecule base sequence T-G-G-C-T-A-C-T carries the information for making insulin, the base sequence would be contained in cells of Langerhans islets located in the pancreas, this being the region for insulin production in mammals. This base sequence would contain the same information regardless of the location. If for instance the base sequence would be inserted into bacteria’s DNA, the bacteria would then manufacture insulin. Though sounding simple, this could be technical in execution. The genetic composition of the cells could be modified to produce new genes having new characters. This describes genetic engineering, also referred to as recombinant DNA technology defined as the alteration of genes of a living organism to yield a genetically modified organism possessing a new genotype (Fry, 2011). During its emergence in the period preceding the 1960s, it referred to any hereditary and reproduction modification of organisms, including selective breeding and artificial insemination. In contrast, the modern day genetic engineering specifically refers to recombinant DNA technology where DNA from a minimum of two sources would be combined and thereafter inserting it into the host organism. The inserted DNA would then replicate and function simultaneously with the host’s DNA (Montaldo, 2006). The synonyms for genetic engineering as cited by Resnik and Vorhaus (2006) include genetic modification, genetic enhancement, germline manipulation, germline therapy, genome manipulation and germline engineering among others. Genetic Engineering The initial step in genetic engineering process as cited by Jones (2011) would be to choose and isolate the genes, commonly growth hormone genes, which would be inserted into the host. Restriction enzymes could be used in isolation, fragmenting DNA and using gel electrophoresis in separating them based on their lengths. Similarly, polymerase chain reaction, PCR could be used in the amplification of gene segment to be then isolated by gel electrophoresis. Well studied genes could be available in genetic libraries whereas known DNA sequence with no gene copies available could be synthesized artificially. The gene to be inserted into the host could be modified for effectiveness and better expression. The promoter region in the gene to be inserted would initiate gene transcription and would be used in controlling the level and location of gene expression. The terminator region serves to end the transcription. The selectable marker determines the transformed cells in the new gene and would in most cases bestow antibiotic resistance on the target organism. Recombinant DNA techniques like molecular cloning, ligations and restriction digests would be used to make the constructs (Resnik & Vorhaus, 2006). Other techniques would call for the insertion of a new genetic material at a specific location in the genome of the host or generating mutations at specific genomic loci that could cause endogenous genes to be knocked out. Genetic engineering has also adopted the recombinant DNA technology to improve antibiotic production. Genetic engineering has been observed to provide scientists with the ability for identification of specific genes, their removal and subsequent cloning so as to be used in a different part within the same organism or on a different one completely, referred to as gene splicing by Jones (2011). For example, the cells from bacteria colonies could be altered through genetic engineering to give rise to hormones, proteins or other substances that could be useful in the treatment of human illnesses. Other techniques used in a similar manner include polymerase chain reaction and treatment by use of hybridomas. Early research using simple organisms like viruses, bacteria and plasmids gave information on cloning and engineering genes. It was noted that bacteria produced enzymes referred to as restriction enzymes that cut chains of DNA at specific places. This enabled the application of these enzymes in cutting DNA into segments with a cut out segment, say one that gives instructions causing a disease getting replaced with one that gives instructions for healthy functioning. Enzymes and indeed other metabolic proteins could be gene coded and cloned to give microorganism that produce antibiotics. In progress has been noted to be the research that involves the transfer mediated by the recombinant DNA of acyltransfarase genes in some bacterial species so as to give cephalosporins, extractable by solvents and transformation that would cause direct and efficient synthesis of amikacin antibiotic and utilizing recombinant DNA technology for the improvement of antibiotic tyrosine production (Starr & McMillan, 2012). When a gene, either in part or whole gets incorporated in another person’s genome, the procedure would be referred to as transgenesis. Montaldo (2006) acknowledges the importance of transgenesis in studying gene functioning, the attributes of animals that keep changing so as to synthesize high value proteins, improving disease resistance or productivity in animals and creating human disease models. This process encompasses living organisms resulting from manipulating endogenous genomic DNA. The most common methods in transgenesis include nuclear transfer and DNA microinjection. A specific fusion gene which contains a gene to be expressed and promoter would be cloned and characterized, paving way for the isolation, purification and testing in cell culture which would then be dyed so as to be used in preliminary gene transfer experiments. Importance of Genetic Engineering in Medicine Genetic engineering has been widely used in various fields including agriculture, research, medicine and industrial applications. Focusing on medicine, genetic engineering has been used to produce insulin in mass, growth hormones in humans, human albumin, follistim used in treating infertility, monoclonal antibodies and various drugs. As observed by Fry (2011), vaccination describes a process where killed, inactivated or weak live viruses or the related toxins would be introduced into the human body through immunization. As such, genetically engineered viruses confer immunity on the host but lack the infectious capacity. Protein injection as a form of vaccination has become common in the recent past due to the provision of certain properties, particularly peptide epitopes that occur in proteins required in the immune system. A new approach to this involves DNA mediated immunization referred to as DNA vaccines involving injection of plasmid DNA which encodes an antigenic protein that would be expressed in the human cells, making the human more immune to the looming disease. Human monoclonal antibodies could be attributed to fusing mouse hybridomas together. Pollack (2012) notes that genetic engineering has played a key role in ensuring adequate supply of previously limited products such as insulin available for people with diabetes. It has also been documented that genetic engineering would be used in the creation of animal models of various diseases affecting humans. Most commonly used animal would be the genetically modified mice which have been used in studying and modeling obesity, cancer, diabetes, aging, substance abuse, Parkinson disease and arthritis. Potential cures would be tested on these mice models. The National Human Genome Research Institute gives the example of Schwarzenegger mice bred in laboratories whose bodies were observed to grow rapidly due to being injected with a muscle growing gene (Hanna, 2006). This intends to coax bodies of patients with serious illnesses to recreate tissues that would have been damaged. This could inform the use of the technology in improving the performance of athletes without detection. Genetically modified pigs have also been used particularly in organ transplantation from pigs to humans. Finally, Resnik and Vorhaus (2006) appreciate the role of genetic engineering in gene therapy where defective genes in humans would be replaced with functional copies, commonly occurring in somatic or germline tissue. The gene inserted into germline tissue could be passed down to the host’s descendants. Gene therapy has found wide application among patients of immune deficiency with trials being undertaken on other disorders of the genes. Pollack (2012) gives the example of Glybera, a European therapy used in treating lipoprotein lipase deficiency whose patients suffered genetic mutation preventing them from producing the enzyme needed for the break-down of fat carrying particles circulating in the bloodstream particularly after meals. Limitations and Ethical and Social Concerns of Genetic Engineering Despite these important roles that genetic engineering plays, gene therapy has been noted to be a dangerous procedure. According to Resnik and Vorhaus (2006), the virus being introduced into the host’s genes, in spite of the silencing of the virulence factors, could pose some negative outcomes including loss of life. Various deaths have indeed been reported with gene therapy including the famous one in 1999 for Jesse Gelsinger (Montaldo, 2006). Similarly, the gene being introduced could also end up landing on an unintended spot causing harm that would be expressed in various unusual ways. Considering its cost, genetic engineering techniques require a lot of money with governments spending massive resources annually in research and development of the technology. Montaldo (2006) acknowledges the ethical dilemma created by genetic engineering, noting that it undermines the social equality principle and creates the problem of unfair advantage to be enjoyed by the individuals with enhanced capacities. Various religious and philosophical objections have also been raised connoting that such processes seem to exalt man above God. The proponents of these philosophies argue that interference with the random offering by nature as wrong. These social and ethical arguments would be noted to generally center on augmentation of functions which would be considered as normal without any interference as opposed to focusing on the resultant improved traits that would alleviate deficiencies or reduce the risk of diseases. There has been also been argument on the potential commercial value that could be realized from genetically engineered substances. The founders of the technology enjoyed huge payments from governments then. The ethical concern that now arises argues on the right of these individuals in making personal financial benefits from the techniques (Montaldo, 2006). In addition, there has been increased concern on what genetic engineering could cause. The debate revolves around, among others, the probability of the altered bacteria creating synthetic forms of substances like insulin to create new forms of bacteria that could be harmful to human health. Despite these concerns, there continues to be massive advancement in genetic engineering techniques. Conclusion Genes play a critical role in influencing health and disease and also in shaping behavior and traits in humans. Researchers have increasingly used genetic technology to determine the contributions of the various genotypes, simultaneously discovering different potential applications of the technology. Genetic engineering would be applied in the identification, replication, modification and transfer of genetic material found in cells or tissues. The techniques involved would use molecular genetics to directly manipulate DNA so as to express the desired genes. These techniques alter the base sequence of DNA so as to give the desired outcome and include recombinant DNA technology, cloning, gene slicing and transgenesis. This alteration of the natural state has elicited social and ethical concerns on the possibility of negative outcome in humans, but genetic engineering remains critical in medicine because it propagates mass production of insulin, creation of animal models of human diseases and its role in gene therapy. Indeed, genetic engineering plays a critical role in ensuring positive outcome in practices in medicine and human health. References Fry, M. (2011). Essential biochemistry for medicine (2nd ed.). Hoboken: John Wiley & Sons. Hanna, K. E. (2006, April). Genetic Enhancement. Bethesda, MD: National Human Genome Research Institute. Retrieved 15 February 2013 from http://www.genome.gov/10004767 Jones, D. (2011). Genetic engineering of a mouse. Yale Journal of Biology and Medicine, 84, 117 – 124. Montaldo, H. (2006). Genetic engineering applications in animal breeding. Electronic Journal of Biotechnology, 9(2), 157 – 170. Pollack, A. (2012, July 20). European agency recommends approval of a gene therapy. The New York Times. Retrieved 15 February 2013 from www.nytimes.com Resnik, D. B. & Vorhaus, D. B. (2006). Genetic modification and genetic determinism. Philosophy, Ethics, and Humanities in Medicine, 1(9). Retrieved 15 February 2013 from http://www.peh-med.com/content/1/1/9 Starr, C. & McMillan, B. (2012). Human biology (9th ed.). Belmont: Cengage Learning. Zachariah, S. M. & Pappachen, L. K. (2009). A study of genetic engineering techniques in biotechnology based pharmaceuticals. The Journal of Nanotechnology, 3(1). 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