CureZone   Log On   Join
Genetically Modified Foods and Organisms Forum
Forum Description
Last Message  27 months ago

This forum is dedicated to the discussion and debate on Genetically Modified Foods and Organisms

A genetically modified organism (GMO) is an organism whose genetic material has been altered using techniques in genetics generally known as recombinant DNA technology. Recombinant DNA technology is the ability to combine DNA molecules from different sources into one molecule in a test tube. Thus, the expression of certain traits, the phenotype of the organism, or the proteins it produces, can be altered through the modification of its genes.

The term generally does not cover organisms whose genetic makeup has been altered by conventional cross breeding or by "mutagenesis" breeding, as these methods predate the discovery of the recombinant DNA techniques. Technically speaking, however, such techniques are by definition genetic modification.

The general principle of producing a GMO is to add genetic material into an organism's genome to generate both new and useful traits. The origins of this genetic engineering were a series of sequential scientific advances from the discovery of DNA to the production of the first recombinant bacteria (E .coli) expressing a frog gene in 1973.[1] This led to concerns in the scientific community about the possible risks from genetic engineering and led to biologists meeting at the Asilomar Conference in Pacific Grove, California. The recommendations laid out from this conference were that government oversight of recombinant DNA research should be established until the technology was deemed safe.[2][3] Herbert Boyer then founded the first company to use recombinant DNA technology, Genentech, and in 1978 the company announced that it had produced a strain of E. coli that could produce the human protein insulin.[4]

In 1986, field tests of a bacterium genetically engineered to protect plants from frost damage (ice-minus bacteria) at a small biotechnology company called Advanced Genetic Sciences of Oakland, California, were repeatedly delayed by opponents of biotechnology. Also in 1986, a proposed field test of a microbe genetically engineered for a pest resistance protein by Monsanto was dropped.[1]

Uses of GMOs
Examples of GMOs are diverse, and include transgenic experimental animals such as mice, several fish species, transgenic plants, or various microscopic organisms altered for the purposes of genetic research or for the production of pharmaceuticals. The term "genetically modified organism" does not necessarily imply, but does include, transgenic substitution of genes from another species, and research is actively being conducted in this field. For example, genes for fluorescent proteins can be co-expressed with complex proteins in cultured cells to facilitate study by biologists, and modified organisms are used in researching the mechanisms of cancer and other diseases.

Increasingly large numbers of pharmaceuticals are produced using GMOs. Researchers are also working towards creating genetically modified organisms that are useful for the industrial market and envrionmentally friendly. Tests are being done to create cotton plants with pre-dyed fibers, soy bean and canola plants that produce a cleaner oil stable enough to be used in manufacturing, and plants that produce materials used for strong, biodegradable plastics.

GloFish: the first genetically modified animal to be sold as a pet.
Transgenic animals
Transgenic animals are animals produced with externally introduced genes. Transgenic animals can be used in many fields and as models to test the effect of certain genes on health. They can be used to produce "enhanced" versions of an animal. They can also be used as bioreactors: animals that produce an extra substance we want. Imagine having a transgenic cow that is modified to produce insulin in large quantities in its milk. This insulin can then be purified from the cows milk and used to treat people with diabetes mellitus.

An example are transgenic flies, which are flies produced with externally introduced genes. Transgenic flies can be used in many fields and as models to test the effect of certain genes on health and development, similar to the usage of transgenic animals. As the fly genome is in general simpler than that of vertebrates, the effect of introducing an external gene is usually more pronounced than in vertebrates.

Controversy over GMOs
See also: Genetically modified food controversies
Genetic modification (GM) is the subject of controversy in its own right [2]. Some see the science itself as intolerable meddling with "natural" order, while others recognize the inability of modern science to fully comprehend all of the potential negative ramifications of gene manipulation.

While some would like to see it banned, others push simply for required labeling of genetically modified food. Other controversies include the definition of patent and property pertaining to products of genetic engineering and the possibility of unforeseen global side effects as a result of modified organisms proliferating. The basic ethical issues involved in genetic research are discussed in the article on genetic engineering.

In 2004, Mendocino County, California became the first county in the United States to ban the production of GMOs. The measure passed with a 57% majority. In 2005, a standing committee of the government of Prince Edward Island in Canada began work to assess a proposal to ban the production of GMOs in the province. PEI has already banned GM potatoes, which account for most of its crop. In California, Trinity and Marin counties have also imposed bans on GM crops, while ordinances to do so were unsuccessful in Butte, San Luis Obispo, Humboldt, and Sonoma counties. Supervisors in the agriculturally-rich counties of Fresno, Kern, Kings, Solano, Sutter, and Tulare have passed resolutions supporting the practice [3].

Currently, there is little international consensus regarding the acceptability and effective role of modified "complete" organisms such as plants or animals. A great deal of the modern research that is illuminating complex biochemical processes and disease mechanisms makes vast use of genetic engineering.

The practice of genetic modification as a scientific technique is not restricted in the United States. Individual genetically modified crops (such as soybeans) are studied before being brought to market, but generally only by the companies providing the modification. This "test by those being tested" practice is common in the United States, where many in the FDA are ex-employees of Monsanto, the largest gene-manipulation firm. Most countries in Europe, Japan, Mexico (among others) have taken the opposite position, stating that genetic modification has not been proven safe, and therefore that they will not accept genetically modified food from the United States or any other country. This issue has been brought before the World Trade Organization, which determined that not allowing GMOs into the country creates an unnecessary obstacle to international trade. Consequently, genetic modification within agriculture is an issue of some strong debate in the United States, the European Union, and some other countries.

Some critics have raised the concern that conventionally bred crop plants can be cross-pollinated (bred) from the pollen of modified plants. Pollen can be dispersed over large areas by wind, animals, and insects. Recent research with creeping bentgrass has lent support to the concern when modified genes were found in normal grass up to 21 km (13 miles) away from the source, and also within close relatives of the same genus (Agrostis) [4]. GM proponents point out that outcrossing, as this process is known as, is not new. The same thing happens with any new open-pollinated crop variety—newly introduced traits can potentially cross out into neighbouring crop plants of the same species and, in some cases, to closely related wild relatives. Defenders of GM technology point out that each GM crop is assessed on a case by case basis to determine if there is any risk associated with the outcrossing of the GM trait into wild plant populations. The fact that a GM plant may outcross with a related wild relative is not, in itself, a risk unless such an occurrence has consequences. If, for example, a herbicide resistance trait was to cross into a wild relative of a crop plant it can be predicted that this would not have any consequences except in areas where herbicides are sprayed, such as a farm. In such a setting the farmer can manage this risk by rotating herbicides. If patented genes are outcrossed, even accidentally, to other commercial fields and a person deliberately selects the outcrossed plants for subsequent planting then the patent holder has the right to control the use of those crops. This was supported in Canadian law in the case of Monsanto Canada Inc. v. Schmeiser. The documentary The Future of Food covers the GMO and Monsanto controversy in more depth.

An often cited controversy is a hypothetical Technology Protection technology (dubbed terminator by non-governmental organization). This yet-to-be-commercialised technology would allow the production of first generation crops that would not generate seeds in the second generation because the plants yield sterile seeds. The patent for this so-called "terminator" gene technology is owned by Delta and Pine Land and the United States Department of Agriculture. Delta and Pine Land was bought by Monsanto in August 2006. In addition to the commercial protection of proprietary technology in selfpollinating crops such as soybean (a generally contentious issue) another purpose of the terminator gene is to prevent the escape of genetically modified traits from crosspollinating crops into wild-type species by sterilizing any resultant hybrids. The terminator gene technology created a backlash amongst those who felt the technology would prevent re-use of seed by farmers growing such terminator varieties in the developing world and was ostensibly a means to exercise patent claims. Use of the terminator technology would also prevent "volunteers", or crops that grow from unharvested seed, a major concern that arose during the Starlink debacle.

In popular culture
Genetically modified characters, whether as heroes, villains, or backdrop, feature prominently in many works of fiction, in particular science fiction and cyberpunk, where it is used as a plot device to explain differences in a character or setting, such as explaining increased longevity or eradication of disease in a fictional civilization.

The videogame character Shadow the Hedgehog was originally a science experiment who was fused with the DNA of Black Doom, causing him to have the genes of aliens as well as hedgehogs. This however, was not revealed until the game Shadow the Hedgehog.

The plot of the 1982 movie Blade Runner revolved around a group of gentically enhanced, artificially constructed replicants, who possessed superior physical and mental capabilities and were used as slaves.

The 1978 movie Plague (aka M3: The Gemini Strain) depicted the hypothetical consequences of an accidental release of a modified bacterium (M3) from a research laboratory into Canadian society and eventually as far away as London [5].

In the Maximum Ride books by James Patterson, the main characters are human/bird transgenics.

In Red Dwarf, mankind turns to GELFs, Genetically Engineered LifeForms, after the robot revolution leaves them with nothing.

Michael Crichton's novel Next is heavily based around the concept of transgenics.

The TV series Dark Angel features transgenic supersoldiers who were enhanced with animal DNA.

The computer game Deus Ex contains two transgenic species: karkians and greasels, which appear to be shark/dogs and lizard/chickens, respectively.

In the Warhammer 40,000 universe, the armies of the galaxy-spanning Imperium of Man make use of genetically-modified Space Marines.

In the XBox 360 Game Crackdown, you play as a genetically engineered soldier, to take out three different gangs.

Genetic engineering, recombinant DNA technology, genetic modification (GM) and gene splicing are terms that are applied to the manipulation of genes, generally implying that the process is outside the organism's natural reproductive process. It involves the isolation, manipulation and reintroduction of DNA into cells or model organisms, usually to express a protein. The aim is to introduce new characteristics or attributes physiologically or physically, such as making a crop resistant to herbicide, introducing a novel trait or enhancing existing ones, or producing a new protein or enzyme. Successful endeavours include the manufacture of human insulin by bacteria, the manufacture of erythropoietin in Chinese hamster ovary cells, and the production of new types of experimental mice such as the OncoMouse (cancer mouse) for research.

Since a protein sequence is specified by a segment of DNA called a gene, novel versions of that protein can be produced by changing the DNA sequence of the gene. There are a number of ways through which this could be achieved. After isolating a section of DNA that includes the gene, the gene or required portion of the gene is cut out. After modification of the sequence if necessary, it may be introduced (spliced) into a different DNA segment or into a vector for transformation into living cells. Daniel Nathans and Hamilton Smith received the 1978 Nobel Prize in physiology or medicine for their isolation of restriction endonucleases, which are able to cut DNA at specific sites. Together with ligase, which can join fragments of DNA together, restriction enzymes formed the initial basis of recombinant DNA technology.

Conservative groups in the United States have argued genetic engineering is wrong and is "doing the work of God"[citation needed], but most scientists believe that genetic engineering is essential to help future discoveries[citation needed]. Professor Stephen Hawking defended the genetic enhancing of our species in order to compete with Artificial intelligence.[1]

The first genetically engineered drug was human insulin, approved by the USA's FDA in 1982. Another early application of genetic engineering was to create human growth hormone as replacement for a drug that was previously extracted from human cadavers. In 1986 the FDA approved the first genetically engineered vaccine for humans, for hepatitis B. Since these early uses of the technology in medicine, the use of GE has expanded to supply many drugs and vaccines.

One of the best known applications of genetic engineering is the creation of genetically modified organisms (GMOs).

There are potentially momentous biotechnological applications of GM, for example oral vaccines produced naturally in fruit, at very low cost.

A radical ambition of some groups is human enhancement via genetics, eventually by molecular engineering. See also: transhumanism.

[edit] Genetic engineering and research
Although there has been a tremendous[1] revolution in the biological sciences in the past twenty years, there is still a great deal that remains to be discovered. The completion of the sequencing of the human genome, as well as the genomes of most agriculturally and scientifically important plants and animals, has increased the possibilities of genetic research immeasurably. Expedient and inexpensive access to comprehensive genetic data has become a reality with billions of sequenced nucleotides already online and annotated.

Now that the rapid sequencing of arbitrarily large genomes has become a simple, if not trivial affair, a much greater challenge will be elucidating function of the extraordinarily complex web of interacting proteins, dubbed the proteome, that constitutes and powers all living things. Genetic modification permits alteration of the primary structure of proteins and has therefore become a powerful tool in analyzing structure-function relationships in protein research. The use of the term "genetic engineering" to describe the experimental genetic modification of whole organisms, however, suggests a level of precision and an understanding of developmental biological principles beyond what has been achieved. Nonetheless, research progress has been made using a wide variety of techniques, including:

Loss of function, such as in a knockout experiment, in which an organism is engineered to lack the activity of one or more genes. This allows the experimenter to analyze the defects caused by this mutation, and can be considerably useful in unearthing the function of a gene. It is used especially frequently in developmental biology. A knockout experiment involves the creation and manipulation of a DNA construct in vitro, which, in a simple knockout, consists of a copy of the desired gene which has been slightly altered such as to cripple its function. The construct is then taken up by embryonic stem cells, where the engineered copy of the gene replaces the organism's own gene. These stem cells are injected into blastocysts, which are implanted into surrogate mothers. Another method, useful in organisms such as Drosophila (fruit fly), is to induce mutations in a large population and then screen the progeny for the desired mutation. A similar process can be used in both plants and prokaryotes.
Gain of function experiments, the logical counterpart of knockouts. These are sometimes performed in conjunction with knockout experiments to more finely establish the function of the desired gene. The process is much the same as that in knockout engineering, except that the construct is designed to increase the function of the gene, usually by providing extra copies of the gene or inducing synthesis of the protein more frequently.
'Tracking' experiments, which seek to gain information about the localization and interaction of the desired protein. One way to do this is to replace the wild-type gene with a 'fusion' gene, which is a juxtaposition of the wild-type gene with a reporting element such as Green Fluorescent Protein (GFP) that will allow easy visualization of the products of the genetic modification. While this is a useful technique, the manipulation can destroy the function of the gene, creating secondary effects and possibly calling into question the results of the experiment. More sophisticated techniques are now in development that can track protein products without mitigating their function, such as the addition of small sequences which will serve as binding motifs to monoclonal antibodies.

Forum Link1:
Forum Link2:


Add This Forum To Your Favorites!

Filter Messages:
order by


Donate to CureZone

Contact Us - About - Sponsors - Stats

Link Exchange - Add URL - How To Exchange Links?

Terms of Service - Privacy Policy - Spam Policy - Disclaimer - Guidelines & Rules

CureZone Newsletter is distributed in partnership with

Copyright 2021

0.4375 sec from