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Journal of Pharmaceutical Research and Opinion 1: 7 (2011) 174 – 177. Contents lists available at www.innovativejournal.in JOURNAL OF PHARMACEUTICAL RESEARCH AND OPINION Journal homepage: http://www.innovativejournal.in/index.php/jpro REVIEW CHARLES DARWIN THEORY OF EVOLUTION AND MORDERN GENETIC ENGINEERING Abalaka M.E, Abbey F.K* Department of Microbiology,Federal University of Technology, Minna,Nigeria. ARTICLE INFO ABSTRACT Received 15 Nov 2011 Accepted 09 Dec 2011 Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins(Hall, B. K et al,2008).Organisms could evolve from one form to another as a result of changes in environment and genetic information which results in variations. As variations and adaptive changes continue over a long period of time, these give rise to diversity of form, structure and function in organisms. This is organic evolution(Mayr E. 1982). The theories of evolution attempt a biological explanation of the diversity of form, structure and function among organisms. Charles Darwin (1859) an English naturalist proposed the theory of evolution.(Goldschmidt,1940). He established that all species of life have descended over time from common ancestry, and proposed the scientific theory that this branching pattern of evolution resulted from a process that he called natural selection. He published his theory with compelling evidence for evolution in his 1859 book On the Origin of Species. This theory had limitations which was the underlying mechanism for hereditary. This limitation is further compounded in modern genetic engineering which involves the direct modification of nucleic acid material of an organism. Corresponding Author: Abbey F.K Department of Microbiology, Federal University of Technology, Minna, Nigeria. [email protected] KeyWords: Charles Darwin’s theory, ancestors, DNA ©2011, JPRO, All Right Reserved. INTRODUCTION Charles Darwin’s theory of evolution is the widely held notion that all life is related and has descended from a common ancestor; the birds and the bananas, the fishes and the flowers all related. Darwin’s general theory presumes the development of life from non-life and stresses a purely naturalistic (undirected)”descent with modification”(Charles Darwin,1859). That is complex creatures evolve from more simplistic anscestors naturally over time. In a nutshell, as random genetic mutations occur within an organism’s genetic code, the beneficial mutations are preserved because they aid survival, a process known as natural selection(Haldane,1932). These beneficial mutations are passed on to the next generation. Over time, beneficial mutations accumulate and the results is an entirely different organism(not just a variation of the original but an entirely different creature). While Darwin’s theory of evolution is a relatively young archetype, the evolutionary worldview itself is as old as antiquity. Acient Greek philosophers such as Anaximander postulated the development of life from nonlife and the evolutionary descent of man from animal(Charles Darwin et al,1858). Charles Darwin simply brought something new to the old philosophy, a plausible mechanism called natural selection.(Bowler,2003) Natural selection acts to preserve and accumulate minor advantageous genetic mutations. Suppose a member of species developed a functional advantage(it grew wings and learned to fly),its offspring would inherit that advantage and pass it to their offsprings The disadvantaged members of the same species would gradually die out, leaving only the superior members of the species. Natural selection is the preservation of a functional advantage that enables a species to compete better in the wild. Natural selection is a naturalistic equivalent to domestic breeding.(Fisher,1930) Over the centuries, human breeders have produced dramatic changes in domestic animal populations by selecting individuals to breed. Breeders eliminate undersirable traits gradually over time. Similarly, natural selection eliminates inferior species gradually over time.Darwin’s theory of evolution is a slow and gradual process.(Herbert, 1991) Natural selection is believed to take advantage of slight successive variations; it can never take a great and sudden leap but must advance by short and sure through small steps. Darwin conceded that if it could be demonstrated that any organ existed, which could not possibly have been formed by numerous successive slight modifications, his theory would break down. Such a complex organ would be known as an irreducibly complex system.(Darwin et al,1858) An irreducibly complex system is one composed of multiple parts all of which are 174 Abbey et. al/ Charles Darwin Theory of Evolution And Mordern Genetic Engineering necessary for the system to function. (Owen, et al,2006 )Richard. Even if one part is missing, the system will fail to function. Every individual part is integral. Thus, such a system could not have evolved slowly piece by piece.On the other hand,Genetic engineering also called genetic modification is the direct human manipulation of an organism’s genome using modern DNA technology. (Resnik et al,2006) It involves the introduction of foreign DNA into the organism of interest which does not require the use of classical genetic methods.(Shukla et al,2009) an organism that is generated through the introduction of recombinant DNA is considered to be genetically modified. Bacteria were the first organism to be modified in 1973 and then mice in 1974.The commonest form of genetic engineering involves the insertion of new genetic material at an unspecified location in the genome of the host. This is done by the isolation and copying of the genetic material of intrest by use of molecular cloning techniques to yield a sequence of DNA which contains the required genetic elements or expression and this construct is then inserted into the host organism(David et al,2006) Genetic engineering methods have been applied in numerous areas including research, biotechnology and medicine. Medicines such as insulin and some human growth hormones are now produced by bacteria. Genetically engineered plants and animals are capable of producing drugs which are cheaper. Genetically engineering does not include traditional animal and plant breeding, invitro fertilization, Induction of polyploidy, mutagenesis and cell fusion techniques that do not use recombinant nucleic acid or genetically modified organisms in the process (The European Parliament and the council of the European Union,2001). If genetic material is added to a host, the resulting organism is said to be transgenic. If genetic material is added from same specie or specie that can naturally breed with the host is employed, the resulting organism is said to be cisgenic. Humans have altered the genome of species for thousands of years via artificial selection and most recently mutagenesis. genetic engineering as a direct modification of nucleic acid material started in the 1970’s.the term genetic engineering was first coined by jack Williamson in his novel published in 1951(Stableford,2004) a year before the role of DNA was confirmed by Alfred Hrasley and Martha chase.Paul berg created the first recombinant DNA by combining DNA from monkey virus sv40 with that of lambda virus. the first transgenic organism by the insertion of antibiotic resistant genes into the plasmid of an e. Coli bacterium. The first trails of genetically engineered plants occurred in France and the USA in 1986.tobacco plants were engineered to be resistant to herbicides(Jackson D.A,1972) In 2010,at J.craig venter institute,scientist announced that they have created the first synthetic bacterial genome and added it to a cell containing no DNA. During the process of genetic engineering, the gene to be inserted into the genetically modified organism must be chosen and isolated. This involves multiplying the gene through polymerase chain reaction (PCR).The gene to be inserted must be combined with other genetic elements to make the modification successful. this is called construct. Most construct contain a promoter and a terminator region as well as a selectable marker gene. Transcription is initiated by the promoter region and can be used to control the location and level of gene expression. The constructs are made using techniques such as restriction digest, ligations and molecular cloning. The most common form of genetic engineering involves inserting new genetic material at random within the host genome(Savage et al,2007) some techniques allow new genetic material to be inserted at specific location in the host genome or generate mutations at specific loci. During the process of genetic engineering, not all cells are transformed. a selective marker is used to differentiate transformed from non-transformed cells. The finding that a recombinant organism contains inserted genes is not sufficient that the genes will be expressed in an appropriate manner in the intended tissues of the recombinant organism. Further analysis uses techniques like PCR,Southern hybridization,and DNA sequencing which serve to determine the chromosomal location and the copy number of the inserted gene. CHARLES DARWIN’S THEORY OF EVOLUTION AND MORDERN GENETIC ENGINEERING Darwin’s theory of evolution is a theory in crises in the light of the advances made in molecular biology, genetic engineering, genetics and biochemistry over the last fifty years( Michael Denton,1996).We know that there are infact tens of thousands of irreducibly complex systems on the cellular level. Specified complexity pervades the microscopic biological world. And we don’t need microscope to observe irreducible complexity. The eye, ear and the heart are all examples of irreducible complexity, though they were not recognized as such in Darwin’s day. Darwin came to understand that any population consists of individuals that are slightly different from one another. Those individuals that have a variation that gives them an advantage in staying alive long enough to reproduce are the ones that pass on their traits more frequently to the next generation. Subsequently, these traits become more and more common and the population evolves. Darwin called this ‘Descent with modification’ Darwin did not believe that the environment was producing variation. He correctly thought that the variation already existed and that nature just selected for the most suitable beak shape and against less useful ones. By the late 1860’s Darwin came to describe this process as survival of the fittest. This is very different from Larmarks incorrect idea that the environment altered the shape of individuals and that these acquired changes were then inherited. An example of evolution arising from natural selection was discovered among peppered moths living near the English industrial cities. These insects have varieties that vary in wing and body coloration from light to dark. During the 19th century, sooty smoke from coal burning furnaces killed lichen on trees and darkened the bark. When moths landed on these trees and other blackened surfaces, the dark coloured ones were harder to spot by birds who ate them and, subsequently, they more often lived long to reproduce over generations. Charles Darwin’s theory hinges on his belief that new organisms are formed as a result of evolutionary changes occurring as a result of adaptation for survival, recent advances in genetics outside genetic engineering shows that the basis of hereditary is the gene which contains genetic materials(DNA).while genetics and genetic engineering is based on genes and DNA (genetic materials),charles Darwin theory of evolution has no basis on genetic materials. charles Darwin based his theory on the fact that complex forms evolve from non complex forms over time. His theories were based on natural selection which acts to accumulate and transform minor advantageous genetic mutations. Charles Darwin’s theory of evolution is a gradual and slow process. on the other 175 Abbey et. al/ Charles Darwin Theory of Evolution And Mordern Genetic Engineering hand, modern genetic engineering is considered a fast system which alters the underlying genetic material to produce modifications in the new organism. Heritable traits are known to be passed from one generation to the next via DNA, a molecule that encodes genetic information.( Ernesto et al,2006)DNA is a long polymer composed of four types of bases. The sequence of bases along a particular DNA molecule specifies the genetic information, in a manner similar to a sequence of letters spelling out a sentence. Before a cell divides, the DNA is copied, so that each of the resulting two cells will inherit the DNA sequence. Portions of a DNA molecule that specify a single functional unit are called genes; different genes have different sequences of bases. Within cells, the long strands of DNA form condensed structures called chromosomes. The specific location of a DNA sequence within a chromosome is known as a locus. If the DNA sequence at a locus varies between individuals, the different forms of this sequence are called alleles. DNA sequences can change through mutations, producing new alleles. If a mutation occurs within a gene, the new allele may affect the trait that the gene controls, altering the phenotype of the organism. However, while this simple correspondence between an allele and a trait works in some cases, most traits are more complex and are controlled by multiple interacting genes. Recent findings have confirmed important examples of heritable changes that cannot be explained by changes to the sequence of nucleotides in the DNA. These phenomena are classed as epigenetic inheritance systems.DNA methylation marking chromatin, self-sustaining metabolic loops, gene silencing by RNA interference and the three dimensional conformation of proteins (such as prions) are areas where epigenetic inheritance systems have been discovered at the organismic level. Modern genetic engineering modifies the basis for heritable traits(DNA) to produced modified organisms and this heritable traits have been proven over time to be reponsible for transmission of inheritance.( Resnik,et al,2006) On the other hand, Charles Darwin’s theory has no basis on any of the recent advances in genetics. Genetic engineering gives us the advantage of producing the organism of choice while Charles Darwin’s evolution produces the organism of choice of the environment since environmental and adaptation requirements are determinants of survivors. He could not explain his theory in a way consistent with known genetic mechanisms. CONCLUSION Modern genetic engineering is based on known genetic mechanisms for the production of modified organisms as a result of changes in the genetic materials of the modified organism and is in contrast with Charles Darwin’s theory of evolution which described changes in organisms without a change in the genetic materials. Genetic engineering though is an artificial scientific method but Charles Darwin proposed his theory as a purely naturalistic method.Charles Darwin’s theory does not also match modern genetic principles because of some irreducible complexes described in the text above. REFERENCES Bowler, Peter J. (2003). Evolution: The History of an Idea (3rd ed.). University of California Press. ISBN 0-52023693-9. Charles Darwin, "On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life," 1859, p. 155. Charles Darwin, "On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life," 1859, p. 162. Darwin, C. & Wallace, A. (1858) On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection. Proceedings of Linnean Society 3 (July): 45-62. David M. Suter, Michel Dubois-Dauphin, Karl-Heinz Krause (2006). "Genetic engineering of embryonic stem cells". Swiss Med Wkly 136 (27-28): 413–415. PMID 16897894 Ernesto Andrianantoandro, Subhayu Basu, David K Kariga & Ron Weiss (16 May 2006). "Synthetic biology: new engineering rules for an emerging discipline". Molecular Systems Biology 2 (2006.0028): 2006.0028. doi:10.1038/msb4100073. PMC 1681505. PMID 16738572. Fisher, R. A. 1930. The Genetical Theory of Natural Selection, Clarendon Press. ISBN 0-19-850440-3 Goldschmidt R. 1940. The material basis of evolution. Yale. Haldane, J.B.S. 1932. The Causes of Evolution, Longman, Green; Princeton University Press reprint, ISBN 0-69102442-1 Fisher, R. A. 1930. The Genetical Theory of Natural Selection, Clarendon Press. ISBN 0-19-850440-3 Hall, B. K.; Hallgrímsson, B., eds (2008). Strickberger's Evolution (4th ed.). Jones & Bartlett. pp. 762. ISBN 0763700665. http://www.jblearning.com/catalog/9780763700669/ Herbert, (1991). "Charles Darwin as a prospective geological author". British Journal for the History of Science (24): 159–192. http://darwinonline.org.uk/content/frameset?viewtype=text&itemID=A 342&pageseq=1. Retrieved 24 October 2008. Jackson, DA; Symons, RH; Berg, P (October 1, 1972). "Biochemical Method for Inserting New Genetic Information into DNA of Simian Virus 40: Circular SV40 DNA Molecules Containing Lambda Phage Genes and the Galactose Operon of Escherichia coli". PNAS 69 (10): 2904– 2909. doi:10.1073/pnas.69.10.2904. PMC 389671. PMID 4342968. Michael Behe, "Darwin's Black Box," 1996. Michael Denton, "Evolution: A Theory in Crisis," 1996, p. 250. Owen, Richard (2006). Paul, C. R.. ed. Fossil Mammalia Part 1. The zoology of the voyage of H.M.S. Beagle. London: Smith Elder and Co. Savage, Neil (Wednesday, August 01, 2007). "Making Gasoline from Bacteria: A biotech startup wants to coax fuels from engineered microbes". Technology Review. http://www.technologyreview.com/biztech/19128/. Retrieved 9/7/2010. Shukla VK, Doyon Y, Miller JC, et al. (May 2009). "Precise genome modification in the crop species Zea mays using zinc-finger nucleases". Nature 459 (7245): 437–41. Bibcode 2009Natur.459..437S. doi:10.1038/nature07992. PMID 19404259. Resnik, David B., and Daniel B. Vorhaus. "Genetic modification and genetic determinism." Philosophy, Ethics, and Humanities in Medicine (2006): 1-11. Stableford, Brian M. (2004). Historical dictionary of science fiction literature. p. 133. ISBN 9780810849389 176 Abbey et. al/ Charles Darwin Theory of Evolution And Mordern Genetic Engineering The European Parliament and the council of the European Union (12 March 2001). Directive on the release of genetically modified organisms (GMOs) Directive 2001/18/EC ANNEX I A. Official Journal of the European Communities. p. page 17. 177