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Transgenic Organisms (transgenic + organism)
Selected AbstractsGerm Line Transformation of Mammals by Pronuclear MicroinjectionEXPERIMENTAL PHYSIOLOGY, Issue 6 2000T. Rülicke The most popular approach for generating transgenic mammals is the direct injection of transgenes into one pronucleus of a fertilized oocyte. In the past 15 years microinjection has been successfully applied in laboratory as well as in farm animals. The frequency of transgenic founders, although highly different between the species, is efficient enough to render this technique applicable to a wide range of mammals. The expression levels and patterns of a transgene are initially influenced by the construction of the transgene. However, the overall phenotype of a transgenic organism is influenced by several genetic and environmental factors. Due to the features of this technique not all of the genetic factors can be experimentally controlled by the scientist. In this article we will emphasize some peculiarities which have to be taken into account for the successful performance of transgenesis by pronuclear microinjection [source] Advances in insect biotechnology for human welfareENTOMOLOGICAL RESEARCH, Issue 2008Thomas A. MILLER Abstract Biotechnology is the latest scientific breakthrough in the history of agriculture. Yet despite the promise of developing new tools for pest and disease control, transgenic organisms have encountered a mixed reception by the lay and scientific public alike. Yields are unable to keep pace with rising costs resulting in a decline in traditional farming. Switching to a new organic growing paradigm is occurring in Korea and the United States today. These new approaches ignore traditional tools that were responsible for the increased yields that support the current affluence and allowed us to protect crops while buying time to find more ecologically-friendly methods. The perception that we understand crop diseases and pests is false and those making this assumption risk destabilizing global food production. There are new pests and diseases that are very difficult to control without these traditional non-organic methods. Invasive species continue to arrive at high rates adding to the burden of farming. Global climate change is already causing changes in the pest and disease complexes and is forcing the entomologist and plant pathologist to make drastic changes to adjust to them. [source] Excision of selectable marker genes from transgenic crops as a concern for environmental biosafetyJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2007Satheesh Natarajan Abstract The main task in the development of transgenic plants is the capability to distinguish between plant cells with an integrated transgene and the bulk of non-transformed cells. Selectable marker genes are required to achieve this goal within the transgene, and to select for their expression. These selectable markers are mostly based on genes conferring antibiotic or herbicide resistance. The presence of the marker gene will lead to unpredictable environmental hazards, so on the basis of economic incentives and safety concerns, several methods, such as site-specific recombination, homologous recombination and co-transformation, have been developed to eliminate these genes from the genome after successful transformation has been achieved. Gene transfer without the incorporation of an antibiotic-resistance marker or herbicide-resistance marker in the host genome should convince the public with regard to the field release of transgenic organisms. Moreover, it would obviate the need for different selectable markers in subsequent rounds of gene transfer into the same host. Copyright © 2007 Society of Chemical Industry [source] Regulatory hurdles for transgenic biofuel cropsBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 4 2009David Lee Abstract Policy-makers have described the many potential benefits that biofuels can provide, but there are numerous challenges in realizing this potential. The technical hurdles to producing biofuels economically and on a scale to replace a significant fraction of petroleum-based transportation fuels have been well described, along with the potential environmental concerns. The use of biotechnology can potentially address many of these technical challenges and environmental concerns, but brings significant regulatory obstacles that have not been discussed extensively in the scientific community. This review will give an overview of some of the approaches being developed to produce transgenic biofuel feedstocks, particularly cellulosic ethanol, and the regulatory process in the United States that oversees the introduction of new transgenic plants. We hope to illustrate that the level of regulation for transgenic organisms is not proportional to their potential risk to human health or to the environment, and that while revisions to the regulatory system in the USA are currently under consideration, further modifications are necessary to reflect the risk level of transgenic crops and realize their benefits. © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source] Biotechnology in Aquaculture: Transgenics and PolyploidyCOMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY, Issue 1 2007Rosalee S. Rasmussen ABSTRACT:, Although capture fisheries have experienced slow to stagnant growth in recent years, the world population has been increasing, with subsequent rises in demands for marine-based foods. One possibility for alleviating potential food shortages and price increases is through aquaculture, which has experienced rapid worldwide expansion. A major focus of research in the aquaculture industry is on the use of biotechnology to increase food availability and reduce production costs, specifically through the manipulation of the genes and chromosomes of cultivated species. Examples include transgenic fish with properties such as increased growth rates, feed conversion efficiency, disease resistance, cold tolerance, and improved metabolism of land-based plants. However, use of transgenic organisms in aquaculture is a very controversial topic due to a number of environmental and human health concerns such as escapement and introduction of genetically modified organisms into the food chain. In response, some transgenic research has also been focused on inducing sterility to reduce the risk of transgenic organisms breeding with wild species. A method of chromosome manipulation, referred to as polyploidy, provides the option of creating sterile organisms, some of which also exhibit increased growth rates. This review paper will discuss recent advances in biotechnology research, specifically in regards to the manipulation of genes and chromosomes, for enhanced cultivation of fish and invertebrates. Major environmental and human health concerns will also be addressed. [source] | |||||||||||||