Genetic Manipulation
Genetic manipulation refers to the deliberate alteration of an organism's genetic material using biotechnology. This process can involve inserting, deleting, or modifying specific genes to produce desired traits or characteristics. In the context of geography, genetic manipulation can be used in agriculture to develop crops with improved resistance to environmental stressors or to enhance productivity.
4 Key excerpts on "Genetic Manipulation"
eBook - ePub- Peter Wheale, René von Schomberg(Authors)
- 2019(Publication Date)
- Routledge(Publisher)
...1 The Social Management of Genetic Engineering: An Introduction Peter Wheale and Ruth M c Nally Many complex technologies pose substantial hazards and risks to individuals, communities, regions, or even to the entire planet. To impose such risks on people without even their tacit consent is undeniably an act of tyranny. (Zimmerman 1995, p. 92.) Genetic engineering is the manipulation of heredity or the hereditary material, and its aim is to alter cells and organisms so that they produce more or different chemicals or perform better or new functions. It is a pre-modern activity in the sense that people have tampered with heredity for as long as they have been cultivating crops and breeding livestock, and are responsible for countless alterations of the inherited properties of life forms on the planet. However, in this century, the science of genetics has transformed the traditional craft of genetic engineering into a modern science-related technology (see Freeman and Soete 1997, p. 15). The basic principles of classical genetics, which were developed between 1910 and 1940, changed the study of inheritance from a descriptive, anecdotal account of various hybrid crosses to a rigorous science. Applications of the principles of classical genetics had a profound effect on crop plant and domestic breeding, as 'rule-of-thumb' breeding procedures were replaced with rational regimes of artificial selection and hybridization, and artificial in vivo mutagenesis was used to generate genetic variation (see, for example, Stent 1971; Maener 1979). Scientific breakthroughs in microbiology, biochemistry and molecular biology since the Second World War comprise what is now often referred to as the 'molecular revolution' in the science of genetics, and it is 'molecular genetics' which underpins recombinant deoxyribo(se)nucleic acid (rDNA) technology...
eBook - ePub- Sandy B. Primrose, Richard Twyman(Authors)
- 2013(Publication Date)
- Wiley-Blackwell(Publisher)
...CHAPTER 1 Gene manipulation in the post-genomics era Introduction Since the beginning of the last century, scientists have been interested in genes. First, they wanted to find out what genes were made of, how they worked, and how they were transmitted from generation to generation with the seemingly mythic ability to control both heredity and variation. Genes were initially thought of in functional terms as hereditary units responsible for the appearance of particular biological characteristics, such as eye or hair color in human beings, but their physical properties were unclear. It was not until the 1940s that genes were shown to be made of DNA, and that a workable physical and functional definition of the gene – a length of DNA encoding a particular protein – was achieved (Box 1.1). Next, scientists wanted to find ways to study the structure, behavior, and activity of genes in more detail. This required the simultaneous development of novel techniques for DNA analysis and manipulation. These developments began in the early 1970s with the first experiments involving the creation and manipulation of recombinant DNA. Thus began the recombinant DNA revolution. Gene manipulation involves the creation and cloning of recombinant DNA The definition of recombinant DNA is any artificially created DNA molecule which brings together DNA sequences that are not usually found together in nature. Gene manipulation refers to any of a variety of sophisticated techniques for the creation of recombinant DNA and, in many cases, its subsequent introduction into living cells. In the developed world there is a precise legal definition of gene manipulation as a result of government legislation to control it...
eBook - ePub- B. W. Higman(Author)
- 2011(Publication Date)
- Wiley-Blackwell(Publisher)
...CHAPTER TWO Genetics and Geography For millions of years, plants and animals evolved through processes of natural selection. As they changed their biological characteristics, and as the earth’s surface and climate experienced dramatic cycles and reshaping, plants and animals changed their geographical locations and dominance through natural migration. By their own means, they found their way from place to place, colonizing and invading, across the globe. The speed with which they could move and their success in achieving dominant status within a niche or region was limited only by their own evolving biological characteristics and by the changing physical conditions in the world around them. Ice and fire, meteor strikes, and massive hurricanes not only created hazards and barriers but also opened opportunities. Different species had different chances. A coconut could float across an ocean and strike root when it washed up on a sandy shore. A crocodile might swim immense distances. Appropriately equipped birds, insects, and seeds might fly or float through the air. But a potato or a breadfruit could not long remain viable in saltwater and a pig needed to feel something solid underfoot. The rules of the game changed with domestication. Only then did human beings begin to play a major role in deciding what would grow where. Only after domestication did the world see a self-conscious “artificial selection” and an active redistribution of plants and animals. Rather than depending on whatever food resources a new place, near or far, might have to offer, migrant groups now carried with them food resources they were familiar with, and had already domesticated, in expectation of planting or raising these plants and animals in new environments. For the first time, biogeographical change followed in the wake of human population movements...
eBook - ePub- Mark Jobling, Edward Hollox, Toomas Kivisild, Chris Tyler-Smith(Authors)
- 2013(Publication Date)
- Garland Science(Publisher)
...This is the case both for statistics applied to a single gene, and for genes identified as outliers in a particular test. Evidence for selection often accumulates slowly, from different studies often in different scientific disciplines, using different statistics and different experimental methods. It is an area where multidisciplinary studies, though difficult in practice, may bear fruit. We discuss specific cases of natural selection for human phenotypes in Chapter 15, and the role of natural selection in disease is considered in Chapters 16 and 17. 6.8 ANALYZING GENETIC DATA IN A GEOGRAPHICAL CONTEXT Until now our consideration of population subdivision has focused solely on a qualitative measure—the population affiliation of a given individual. This neglects some quantitative knowledge about each data point, namely its geo-graphical location. Individuals 1, 2, and 3 may belong to populations A, B, and C respectively; however, if populations A and B are neighbors, whereas C is further away, some information has been overlooked. By incorporating this information we can start to integrate genetic data with information about the landscape from which they were sampled. For example, high levels of differentiation between two nearby populations may result from the presence of a mountain range separating them. By relating genetic data to specific geographical locations we can also attempt to integrate patterns of modern diversity with past geographical processes, for example, sea level changes that resulted in the formation of land bridges. Geographical analyses of genetic data allow us to partially disentangle the relative contributions of history and geography to modern genetic diversity. 34 In the absence of external, nongenetic, information, it can be difficult to discern whether geographical constraints or historical episodes account for observed patterns of genetic diversity...
