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Recombinant technologies in micro-organisms being used to produce commercial and medically useful proteins like insulin are fairly common.
However some proteins are still produced commercially in genetically modified animals. Why are animals a better choice than microorganisms, and which are the most common proteins produced this way?
The rationale for the choice of higher organisms as the producing source is based on costs and biological activity.
- Biological activity. In their active forms, various proteins have post-translational modifications (i.e. glycosylation) which are difficult to reproduce in bacteria. Alan's answer is already exhaustive.
Costs. Mammalian cell lines are easier to generate and maintain but suffer from genetic and epigenetic instability (the transgene can be lost or inactivated). Contrarywise, transgenic animals require more investment but once established that the transgene is present in the germline and breed through, the protein can be produced in larger quantities with ~1/10 of the costs required to setup a GMP-bioreactor. This is particularly appealing for small pharmaceutical niches, i.e. drugs targeting rare diseases: if the market is small, farming few goats can be more profitable than building and maintaining sterile bioreactors. Downstream purification facilities are however required for both cellular and animal farms. That's why animal models that produce high levels of the therapeutic protein in secreted matrices (i.e. milk, egg white) are preferred: this facilitates bulk storage of unpurified protein prior to purification.
A good and recent review comparing models and strategies is from Wang et al., Expression Systems and Species Used for Transgenic Animal Bioreactors (doi:10.1155/2013/580463).
To stay updated on recombinant proteins from transgenic farms entering the market, the official reference would probably be the FDA section on Biologics. Two companies actively working on transgenic farms are GTC Biotherapeutics and Synageva.
GTC Biotherapeutics produces human antithrombin alfa (ATryn) in the milk of transgenic goats, for use in patients with hereditary antithrombin deficiency (HD). Quoting the ATryn executive report:
Antithrombin III (recombinant) is a highly purified, well characterized recombinant glycoprotein consisting of432 amino acids, 3 disulphide bridges between cysteine residues and 4-N linked glycosylation sites, identical to human plasma-derived antithrombin. Recombinant human antithrombin is produced in the milk of transgenic goats. For expression of rhAT, the DNA construct contained a goat beta casein promoter with the cDNA coding region for human antithrombin (hAT). The DNA construct was microinjected into fertilized one-cell goat embryos, which were transFerred to female recipients. Kids born from the recipients were tested for presence of the transgene and expression of the human protein. A founder transgenic goat was selected from which subsequent offspring were generated by natural breeding to give rise to a production herd of hAT transgenic goats, which are milked to provide the source material for downstream purification.
Synageva produces Sebelipase alfa (SBC-102) in the egg white of transgenic hens, for use as an enzyme replacement for Lysosomal Acid Lipase (LAL) Deficiency. I think they are in clinical phase 2/3 (not yet on the market). According to their 2012 Annual Report:
Our proprietary vectors allow incorporation of the gene of interest into the genome of normal cells of an avian (Gallus) with selective expression of the resulting protein in the oviduct tissues and secretion into EW. The importance of this cellular environment for therapeutic protein expression is highlighted by the tight consistency of post-translational modification, including glycosylation, seen in proteins manufactured using our platform compared to cell culture produced material. Furthermore, our expression system yields consistent expression levels and quality of protein within production lines and through multiple generations.
ATryn is a human antithrombin produced in the milk of transgenic goats by GTC Biotherapeutics. It has FDA approval and I believe that it is available for prescription in the USA.
Added later, after the emphasis of the question changed somewhat.
Proteins produced in a mammalian system are more likely to have post-translational modifications that are much closer to those found on the human protein. Antithrombin, for example, has four disulphide bonds and four glycosylation sites. Although it is reasonable to assume that the disulphide bonds would be correctly formed in a eukaryotic microorganism, the same isn't true of the glycosylation: microbial glycans differ from mammalian glycans, and these differences could affect the stability of the protein in the mammalian bloodstream, or the response of the mammalian immune system to the protein. Mammalian cells in culture could be used but are, of course, quite fastidious. So the holy grail of recombinant protein production has always been to get the protein secreted into an animal's milk, allowing the use of very cheap feedstocks and the easy harvest of the protein over a period of years, notwithstanding @shigeta's remarks.
Genetically Modified World: Part IIDecades of study into how to manufacture products using genetically modified bacteria (usually <em>E. coli</em>, shown above at high resolution), have made available to us today an astounding array of medical and food creations generated in such modified <em>E. coli</em> we've even coaxed these critters into producing silk and pictures!
When thinking about genetically modified organisms (GMOs), the first things that usually come to mind are GM plants (which were discussed last week) and animals, which overlooks possibly the most important group of all: GM microorganisms.
Through decades of development, the products of these miniscule critters have come to affect our daily lives. They have already become essential to the medical and food processing industries. Perhaps one day, they will also be critical to the agricultural and energy-production businesses, among others.
The First GMO: In the early 1970s, Herbert W. Boyer and colleagues (at the University of California, San Francisco, and Stanford University School of Medicine) created what is generally considered to be the first genetically modified organism. That organism was a microorganism, specifically the bacteria Escherichia coli (E. coli). (While we’re most familiar with pathogenic E. coli strains through the headlines they occasionally make, there are actually many strains of E. coli that naturally live in our stomachs as a part of its rich, and essential, micro-flora.) Bacteria like E. coli have relatively simple genetics compared to plants and animals, which is part of why researchers have used them in genetic manipulation studies for decades. Additionally, E. coli reproduce quickly and can be grown in large numbers relatively cheaply.
So how did Boyer and colleagues “modify” the genetics of E. coli? Very simply put, the researchers put the DNA of a gene known to confer antibiotic resistance into the bacteria, and showed that the modified bacteria became resistant to the antibiotic. But, of course, it’s a bit more complicated than this. The antibiotic resistance gene was not sent into the bacteria all alone it was delivered in a package called a “plasmid,” which is a piece of DNA (usually circular) that tells the cell to make more copies of the plasmid—along with any genes that are in it, like the antibiotic resistance gene. Boyer’s team showed that two different plasmids could be cut open and recombined to make a new, unique plasmid. (This is why it is called “recombinant” technology.)
This laid the foundation for a whole new enterprise.
What exactly were the implications of Boyer’s work? That desired proteins could be made by bacteria in vast quantities, without the need for the harsh chemicals and extreme conditions that chemical synthesis often requires. On a single plasmid, researchers could not only put a gene that makes the bacteria become antibiotic resistant, but they could also insert a gene that would make the bacteria manufacture some protein of interest. While bacteria are pretty good at incorporating foreign DNA they’re exposed to, compared to most organisms, such efforts are still nowhere near 100 percent successful. Consequently, to make sure the bacteria have taken up the plasmid researchers want them to take up, they can expose the bacteria to an antibiotic. The ones with the plasmid will live, the others will die. With the desired bacteria selected out, they can be easily, rapidly grown to great numbers and then stimulated (by exposure to a certain protein) to make the desired protein. Because the bacteria have been made to focus all their energies on producing this protein, they often will die as the protein is being harvested, but produce a lot of protein in the process. This strategy has become an essential technique, used routinely in laboratories across the world today for a variety of purposes.
Medical Applications: Many quickly realized the implications of this new recombinant technology. In the mid-1970s, Boyer went on to found Genentech, often considered the first biotechnology company. In 1977, the first human protein created in another organism was produced Genentech made E. coli that could turn out the human protein somatostatin (which regulates hormones in the body, among other functions).
A year later, Genentech succeeded in modifying bacteria to make human insulin, which became the first GMO-produced product on the market in 1982. Insulin is needed to treat patients with type 1 diabetes, and can control the progression of type 2 diabetes in some patients. Insulin specifically stimulates the body to take sugar (specifically glucose) out of the blood stream and put it into different tissues (i.e. the liver, fat tissue, and muscle), where it is stored until needed. When insulin levels are low, or when a person becomes insulin resistant (their tissues no longer respond to normal levels of insulin), then high blood sugar levels can result, which can cause diabetes. Before Genentech created a “recombinant” source of human insulin, all medical insulin was harvested from the pancreases of pigs or cows. In 2007, sales of insulin products estimated around $8 billion globally, and they will almost surely increase with time. (All GM-produced proteins must be chemically pure and safe, by the way, just as any non-GM protein must, to be approved for use.)
In the 1980s, Genentech competed with other biotechnology companies to be first in creating recombinant blood-clotting factors. Why clotting factors? Clotting factors are necessary for people with hemophilia to survive. But in the early 1980s, significant amounts of stored clotting factors that had been derived from human plasma were found to be contaminated with HIV. Genentech won the race its scientists were able to make several clotting factors in the laboratory (e.g. anti-hemophilic factor, or factor VII, and factor IX).
By now, a wide variety of drugs, hormones, and other products have been created in microorganisms for the medical market. This includes erythropoietin (which regulates red blood cell production), interferons (which stimulate the immune system), vaccines (e.g. against the Hepatitis B virus), human growth hormone (hGH), and many more. Most recently in the medical field, bacteria are in clinical trials that may prevent cavities, and other bacteria are being created that may possibly block HIV infection.
It’s What’s for Breakfast! Today, many of the food additives we consume on a daily basis are made by GM microorganisms. To name just a few, the list includes vitamins (B2, C), amino acids that improve flavors (e.g. aspartame), food additives (e.g. xanthan), food preservatives (e.g. nisin), enzymes used in food during specific chemical reactions (e.g. making cheese, breads, certain alcohols, and some sugars), and many more. While some of the microorganisms used may naturally make these products and are only coaxed into producing higher quantities, other microorganisms do not and must have the foreign gene inserted in them to do so.
Release into the Environment: The U.S. Environmental Protection Agency (EPA) approved the first use of genetically modified bacteria in the environment in 1985. In that particular case, researchers had taken bacteria that normally encourage ice formation on plants (specifically Pseudonomas syringae and P. fluorescens) and got rid of a gene that the bacteria needed to do this. Consequently, plants colonized with these modified bacteria do not form frost until around 23 degrees Fahrenheit, saving them from damages brought upon plants by an early frost, or unusually cold weather.
Researchers soon explored another agricultural area that could greatly benefit from GM bacteria: the creation of improved nitrogen-fixing bacteria to help increase legume growth. Legumes (which include beans, lentils, peanuts, soy, alfalfa, clover, and more) are distinguished by their ability to capture nitrogen from the atmosphere, which they accomplish through a symbiotic relationship with a group of bacteria (rhizobia) that live in their roots. The bacteria Sinorhizobium meliloti, which can colonize multiple types of legumes, has been of particular interest. In some field studies, legumes with genetically modified S. meliloti had improved plant growth.
However, some of these studies have revealed an area of concern for using GM microorganisms: While the introduced bacteria (which is dependent on the legume hosts) was often undetectable after a few weeks or a year, sometimes it persisted in soil for more than two years. There have also been concerns that the genes of persistent GM microorganisms may be transferred to other, native bacteria, or to the organisms that consume the bacteria. Ongoing work is being done to address such issues.
More recently, genetically modified bacteria has been used to clean up the environment. In one such example, researchers have used rhizobia bacteria (specifically our friend S. meliloti again) and modified them to be able to break down a compound related to TNT. When alfalfa seeds were coated with these modified bacteria and planted in soil with the compound, the bacteria could reduce the pollution levels while stimulating plant growth.
In the works …: A variety of creative applications for using genetically modified microorganisms have been explored over the last decade.
In 2005, light-sensitive E. coli were created and used to create a kind of slow-action, high-resolution camera.
An array of yeast strains have been modified that can convert sugars to ethanol (which we currently mostly harvest from corn), which could be a valuable alternative energy source. Similarly, many efforts have been invested in creating gasoline (crude oil) from microorganisms.
Just last week, there was a breakthrough in generating stronger, lighter silk from bacteria. They’ve become more efficient than ever (generating one to two grams of silk per liter of bacteria), but how to efficiently put these silk proteins together into useable threads remains a big problem.
The Future: GM microorganisms have certainly been a boon for the medical and food industries, not to mention general laboratories everywhere. They also hold promise for creative applications and possibly for well-needed alternative energy sources. However, there is still concern over the release of GM microorganisms into the environment in general, more observational studies on the effects of these microorganisms on their new habitats would be beneficial.
Check “Biology Bytes” next week for Part III of this series on the “Genetically Modified World,” where we will explore the amazing array of genetically modified animals that have been created.
British company Oxitec has created genetically modified male mosquitoes that carry a “self-limiting gene”. When they are released into the wild and mate with females their offspring do not reach adulthood, so crucially do not contribute to the spread of the Zika virus. Other researchers are looking at using genetic modification to curb the spread of malaria.
Rosita Isa, a cow genetically modified to produce human-like milk. Photograph: INTA (National Agricultural Technology Institute Argentina)
Scientists in both China and Argentina have genetically engineered cows to produce milk similar in composition to that made by humans. After modifying embryos, an Argentinian cow – Rosita Isa – was born that expressed milk containing proteins present in human milk but lacking in cow milk. However, there are a number of scientific, safety and taste issues that would have to be overcome before this replaces “mother’s milk” for infants.
Gene-edited chicks at the Roslin Institute. Photograph: Courtesy of Valerie White/Norrie Russell/Roslin Institute
Production, safety and efficacy
Drug research is a unique multi-disciplinary process leading to the development of novel therapeutic agents for disease states that have unmet needs. 13 The search for new biopharmaceuticals is driven by a medical need and by the perceived likelihood of technological success, as determined by both therapeutic efficacy and safety parameters. There are several factors to consider for the safety testing of a new biopharmaceuticals. 14 Because of the protein nature of most biopharmaceutical products, few non-allergic adverse reactions other than those attributable to the primary pharmacological activity are anticipated. Nevertheless, both Good Laboratory Practice and Good Manufacturing Practice, as established for other modes of pharmaceutical production, are essential to plant made pharmaceuticals. Before experimental or clinical use is initiated, it is critical to have fully-characterized, contaminant-free materials, as well as appropriate quality assurance so that both the product itself and the therapeutic results will be reproducible. New pharmaceutical agents derived through plant biotechnology must be subjected to the same purity, quality-control, and safety standards as materials derived from bacterial or mammalian cell systems or from other traditional sources such as vaccine production.
Sites used for the cultivation of genetically modified plants have in some cases been disrupted or destroyed by individuals opposed to the use of plant biotechnology, raising additional security concerns. In part, these concerns can be addressed via increased field site monitoring and security, and the use of enclosed environments (greenhouses) for small scale operations. The relatively small scale and favourable economics of biopharmaceutical operations allows the placement of field operations in geopolitical locations selected for optimal security, with subsequent shipping of raw or processed materials.
Transgenic plants have the added safety feature of freedom from human or animal pathogens. 8 Additionally, plant cells are capable of producing complex proteins while largely avoiding the presence of endotoxins in bacterial systems. Endotoxins are often difficult to remove and can contaminate a final product. Thus, there is intrinsic safety and value in using plants as a source of recombinant protein. 15 However, as with all plant-derived pharmaceuticals, appropriate measures must be taken to eliminate undesirable plant-derived proteins or other biomolecules and to control the presence of fungal toxins or of pesticides used in plant production. 11
Safety evaluations must consider possible non-target organ responses as well as the entire gamut of anticipated and unanticipated side-effects as with any bio-pharmaceutical product. Somewhat unique to plant-produced pharmaceuticals are potential effects on non-target species such as butterflies, honeybee, and other wildlife at or near the growing sites. Fortunately, in most instances, the effect on non-target species is limited by the fact that proteins are a normal part of the diet, are readily digested, and are degraded in the environment. Further, many biopharmaceuticals proteins, especially antibodies, are highly species-specific in their effects.
Pharmaceutical production in plants may create the potential for the flow of pharmaceutical materials into the human food chain, especially when food crops are used. This could occur as a result of inadvertent cross-contamination of foodstuffs, through spontaneous growth of genetically engineered plants where they are not desired, or by virtue of pollen flow with some plants (e.g. corn), but not others (e.g. potato). While some have therefore suggested restricting pharmaceutical production to non-food crops such as tobacco, it is the food crops that present the greatest opportunities for efficient production of biopharmaceuticals and that will be most useful for the production of edible vaccines.
Because of the potential for adventitious presence in food, care must be exercised in the production of biopharmaceuticals in food crops. Fortunately, acreage requirements for pharmaceutical production are limited, with metric ton protein production being feasible with >5000 acres of corn. 9 This allows for production under tightly controlled conditions which include production in areas of the country where the crop in question is not routinely grown, the use of physical isolation distances and temporal separation to prevent cross-pollination with food crops, the use of de-tasseling and/or male-sterile traits to control pollen flow, dedicated harvest and storage equipment, and controlled processing separate from all food crops. Unlike commodity crops, plant production of pharmaceuticals should be performed only under tightly controlled conditions similar to those of other pharmaceutical manufacturing and production standards have been developed jointly by industry, USDA, FDA, and international organizations. 12 These standards are enforced in the US through USDA and FDA, and compliance is further encouraged by the desire of producers to avoid potential liability and infractions. FDA required Good Manufacturing Practice necessitates extensive control of field access, harvest, and product disposition.
While production controls are necessary and appropriate, it should be kept in mind that the majority of therapeutic proteins are not anticipated to have any pharmacological activity when ingested, and are thus unlikely to present a safety issue in the event of accidental contamination of foodstuffs. For example, antibodies, insulin, growth hormone, and most other proteins produce few, if any, systemic pharmacological effects by the oral route. This does not preclude the possibility of local effects on the gastro-intestinal tract or the possibility of immunological effects, as seen in the context of oral vaccines, where such an effect is introduced by design. In fact, one plant-derived antibody directed against epithelial cellular adhesion molecules was withdrawn from clinical development as a result of gastro-intestinal side-effects believed to be due to binding to the relevant antigen, which is expressed in the GI tract. 8 This is a result of the antigenic specificity of the antibody, and is not attributable to the plant-derived nature of the molecule. While a case-by-case determination of risk will be necessary when considering proteins for food crop applications, it appears that the majority of proteins would present no great hazard to the public in the event that control technologies should fail to be fully effective.
3. Does conventional plant breeding have effects on health and the environment?
In conventional plant breeding, little attention has been paid to the possible impacts of new plant varieties on food safety or the environment. Nonetheless, this kind of breeding has sometimes caused negative effects on human health. For instance, a cultivated crop variety created by conventional cross breeding can contain excessive levels of naturally occurring toxins.
The introduction of genetically modified plants has raised some concerns that gene transfer could occur in the field between cultivated and wild plants and such concerns also apply to conventional crops. Such transfers have occasionally been reported but are generally not considered a problem. More.
Genetic engineering can be done with plants, animals, or bacteria and other very small organisms. Genetic engineering allows scientists to move desired genes from one plant or animal into another. Genes can also be moved from an animal to a plant or vice versa. Another name for this is genetically modified organisms, or GMOs.
The process to create GE foods is different than selective breeding. This involves selecting plants or animals with desired traits and breeding them. Over time, this results in offspring with those desired traits.
One of the problems with selective breeding is that it can also result in traits that are not desired. Genetic engineering allows scientists to select one specific gene to implant. This avoids introducing other genes with undesirable traits. Genetic engineering also helps speed up the process of creating new foods with desired traits.
The possible benefits of genetic engineering include:
- More nutritious food
- Tastier food
- Disease- and drought-resistant plants that require fewer environmental resources (such as water and fertilizer)
- Less use of pesticides
- Increased supply of food with reduced cost and longer shelf life
- Faster growing plants and animals
- Food with more desirable traits, such as potatoes that produce less of a cancer-causing substance when fried
- Medicinal foods that could be used as vaccines or other medicines
Some people have expressed concerns about GE foods, such as:
- Creation of foods that can cause an allergic or toxic reaction
- Unexpected or harmful genetic changes
- Inadvertent transfer of genes from one GM plant or animal to another plant or animal not intended for genetic modification
- Foods that are less nutritious
These concerns have thus far been unfounded. None of the GE foods used today have caused any of these problems. The US Food and Drug Administration (FDA) assesses all GE foods to make sure they are safe before allowing them to be sold. In addition to the FDA, the US Environmental Protection Agency (EPA) and the US Department of Agriculture (USDA) regulate bioengineered plants and animals. They assess the safety of GE foods to humans, animals, plants, and the environment.
What GMO crops are grown and sold in the United States?
Only a few types of GMO crops are grown in the United States, but some of these GMOs make up a large percentage of the crop grown (e.g., soybeans, corn, sugar beets, canola, and cotton).
In 2018, GMO soybeans made up 94% of all soybeans planted, GMO cotton made up 94% of all cotton planted, and 92% of corn planted was GMO corn.
In 2013, GMO canola made up 95% of canola planted while GMO sugar beets made up 99.9% of all sugar beets harvested.
Most GMO plants are used to make ingredients that are then used in other food products, for example, cornstarch made from GMO corn or sugar made from GMO sugar beets.
Corn is the most commonly grown crop in the United States, and most of it is GMO. Most GMO corn is created to resist insect pests or tolerate herbicides. Bacillus thuringiensis (Bt) corn is a GMO corn that produces proteins that are toxic to certain insect pests but not to humans, pets, livestock, or other animals. These are the same types of proteins that organic farmers use to control insect pests, and they do not harm other, beneficial insects such as ladybugs. GMO Bt corn reduces the need for spraying insecticides while still preventing insect damage. While a lot of GMO corn goes into processed foods and drinks, most of it is used to feed livestock, like cows, and poultry, like chickens.
Most soy grown in the United States is GMO soy. Most GMO soy is used for food for animals, predominantly poultry and livestock, and making soybean oil. It is also used as ingredients (lecithin, emulsifiers, and proteins) in processed foods.
GMO cotton was created to be resistant to bollworms and helped revive the Alabama cotton industry. GMO cotton not only provides a reliable source of cotton for the textile industry, it is also used to make cottonseed oil, which is used in packaged foods and in many restaurants for frying. GMO cottonseed meal and hulls are also used in food for animals.
Some GMO potatoes were developed to resist insect pests and disease. In addition, some GMO potato varieties have been developed to resist bruising and browning that can occur when potatoes are packaged, stored, and transported, or even cut in your kitchen. While browning does not change the quality of the potato, it often leads to food being unnecessarily thrown away because people mistakenly believe browned food is spoiled.
By the 1990s, ringspot virus disease had nearly wiped out Hawaii’s papaya crop, and in the process almost destroyed the papaya industry in Hawaii. A GMO papaya, named the Rainbow papaya, was created to resist ringspot virus. This GMO saved papaya farming on the Hawaiian Islands.
GMO summer squash is resistant to some plant viruses. Squash was one of the first GMOs on the market, but it is not widely grown.
GMO canola is used mostly to make cooking oil and margarine. Canola seed meal can also be used in food for animals. Canola oil is used in many packaged foods to improve food consistency. Most GMO canola is resistant to herbicides and helps farmers to more easily control weeds in their fields.
GMO alfalfa is primarily used to feed cattle—mostly dairy cows. Most GMO alfalfa is resistant to herbicides, allowing farmers to spray the crops to protect them against destructive weeds that can reduce alfalfa production and lower the nutritional quality of the hay.
A few varieties of GMO apples were developed to resist browning after being cut. This helps cut down on food waste, as many consumers think brown apples are spoiled.
Sugar beets are used to make granulated sugar. More than half the granulated sugar packaged for grocery store shelves is made from GMO sugar beets. Because GMO sugar beets are resistant to herbicides, growing GMO sugar beets helps farmers control weeds in their fields.
Genetically Modified organisms (GMOs) uses, advantages and disadvantages
Genetically modified organisms (GMOs) are the form of scientific farming where the chemicals are pumped to the crops to increase the product sizes and yield , Although this method is highly debated and it has become increasingly common in everyday foods .
Advantages of GMOs
Genetically Modified organisms ( GMOs ) are the effective ways to provide the farmers a larger profit, while making them spend less time on the resources, They are economically beneficial because they are used to repel the pests that prevents the need for the pesticides to be used that means more savings .
GMOs are known to decrease the food prices due to the advanced crops and lower cost that can lead to cheaper food, It will certainly help the families that can not afford to buy the food they need for everyday consumption, so, The starvation will be prevented .
GMO process includes adding new genetic material into the organism’s genome , GMOs reduce the prices for the consumers , They are more nourishing to the body & they are proven to be effective , GMOs crops are safe for the human consumption and they are safer compared to the traditional crops .
Genetically modified organisms
GMO crops increases the genetic alterations knowledge and it makes the genes in the crops more advantageous for the human consumption and production, The plants will be temperature resistant or produce higher yields, It offers greater genetic diversity in different regions where the climate limits the productivity .
GMO crops planted add the nutritional value to the crops that lack necessary vitamins and nutrients, GMOs offers increased flavor and nutrition, Along with the resistances to the insects and the disease , They will help the malnourished populations receive more nutrients from their diet .
We have made pesticide resistant plants so that the farmers can use the right kinds of the pesticides to get rid of the insects and not inhibit the plant growth , there will be fewer insects and pests to eat the crops and the crops will grow without being bothered by the pesticides .
Genetically Modified Crops offer the stable & efficient way to sustain enough crops to feed the growing population of the people in the world, GMOs keep the food affordable , when more crops are yielded, the prices can be much lower .
Genetically modified foods ( GMOs ) have a longer shelf life , So , they will last and stay fresh during the transportation and the storage , The crops are more productive and have a larger yield , They will be more resistant & they will stay ripe for long periods, more GMO crops can be grown on relatively small parcels of land .
GMOs increase the resistance to the pests, the weeds and the disease, The crops are more capable of thriving in the regions with poor soil or adverse climates, they require less herbicides & pesticides, So, They will be more environment friendly.
GMOs can be dangerous to some insects that are important to our ecosystem because the new genes of crops can be deadly to some insects such as the butterflies which are not actually dangerous to the crops , The critics claim that GMOs can cause particular disease or illnesses .
The genetically modified crops can damage the environment , They may cause the threat to the environment , This is because it is not the natural way to plant and cultivate the crops , Possible greed or self-indulgence of the manufacturers and the companies of GMOs , This is due to the profit which can be acquired .
GMO strains have the potential to change the agriculture , GMOs cause unwanted residual effects, They can leave the unwanted residual substances which can stay in the soil for extended periods of time, Genetically modified foods have the unnatural tastes compared with the ordinary foods due to the substances that were added to their composition .
GMOs threaten the crop diversity, GM genes can spread to the other organic farm crops and threaten the crop diversity in the agriculture, And if the crop diversity decreases, it will have the direct impact on our entire ecosystem .
The pollen from the genetically modified plants is contaminated & will have the same resistance properties as the crops, When this pollen is around the other plants, they cross pollinate, GMO foods can encourage the authorities to implement higher tariffs to the merchants , who will be selling them .
Some genetically modified foods have the antibiotic features which are built into them, making them resistant or immune to the viruses or the diseases, these antibiotic markers will persist in our body and they will render actual antibiotic medications less effective .
The resent genetically modified foods can pose significant allergy risks to the people, The genetic modification adds the proteins that are not indigenous to the original animal or plant which may cause new allergic reactions in our body .
Some organisms in the ecosystem can be harmed, When we remove a certain pest that is harmful to the crops, we can remove the food source for a certain species, genetically modified crops can cause toxic to some organisms that can lead to their reduced numbers or even extinction.
GMO foods contain the substances that may cause the diseases & the death to many species , The humans , mice and butterflies can not survive with these foods, GMO can create new diseases, they are modified using viruses and bacteria and it can threat the human health.
The genetically modified foods may escape into the wild, The genes from the commercial crops that are resistant to the herbicides may cross into the wild weed population, So, They create super-weeds that have become impossible to kill.
Some countries can use the genetic engineering of foods as a weapon against their enemies, these products can kill a lot of individuals in the world by using the harmful diseases, Genetically modified food can be a costly and lengthy process.
GENETICALLY MODIFIED ORGANISMS
For centuries, humans have altered plants and animals by selective reproduction (breeding, hybridizing). As a result, we have a wide range of domestic animals and plants grown for food and for a variety of non-food uses (such as for fibers and decorative purposes and as a source of fuel). These efforts to adjust the characteristics of organisms in nature do not involve direct genetic modification by humans, but involve human actions working with existing natural processes for selection of traits. These traits are in the genes, so there are some differences in the genes of the original and modified versions of the plants and animals.
Direct genetic modification is a relatively new process based on a set of technologies that alter the genetic makeup of living organisms, including animals, plants, bacteria, or fungi by inserting genes rather than using cross-breeding and selection techniques. The purpose of the modification of the genes is to derive certain benefits. Genetic modification is accomplished by inserting one or more genes from one organism into a different organism (for example, from bacteria into a plant or from one species of plant into another). Combining genes from different organisms is known as recombinant DNA technology ("gene splicing"), and the resulting organism is said to be "genetically modified," "genetically engineered," or "transgenic." The end product we use may be part of the genetically modified organism itself (e.g., the beans of the soy plant) or something produced by the modified organism (for example, a drug produced by fermentation using modified bacteria or fungi).
PROCESS AND PRODUCTION
Insulin production is started by the inoculation of a vessel of culture medium with a genetically modified E. coli bacterium. The E. coli have had a human gene spliced into their DNA compelling them to produce human insulin. The insulin is harvested by lysing the dead bacteria and then separating out the pre-insulin from the rest by centrifugation and filtration. The pre-insulin has then to be "folded" into its active tertiary structure by treatment in a refolding vessel with buffers of various concentrations. After enzymatic cleavage of this product and chromatographic separation, the insulin product is crystallized, deep frozen (under clean room conditions), and is then ready for fill and finish.
The first reported recombination of genetic material was in 1973, so this technology is just over 30 years old. One of the first applications was the production of insulin by bacteria (insulin to be used for treating diabetics was previously derived from pig pancreas) the recombinant insulin product was approved by the FDA in 1982. The bacteria used for this purpose is a strain of E. coli , a common organism (it is a major bacteria in the human intestinal tract), into which the human insulin gene is inserted. The advantage of this technology is that the product matches human insulin exactly and it is cheaper to produce the pig product is more likely to cause allergic reactions.
A few years later, in 1988, the first field tests of a genetically modified food plant were undertaken in Canada this was for the canola plant that yields a very desirable vegetable oil (lowest in saturated fat high in cholesterol-lowering mono-unsaturated fat best large-scale plant source of omega-3 fatty acids). The genetic modification increased the yield and decreased the need for fertilizers, lowering the price. But, it wasn't until 10 years ago, in 1996, that commercial production of genetically modified (GM or GMO) crops was undertaken: these involved not only canola, but also corn, potatoes, and cotton.
The primary focus of the research on genetic modification involves locating genes that can produce the desired results-such as those conferring insect resistance, reducing sensitivity to herbicides, increasing the amount of desired nutrients, or preventing fruits from rotting as quickly as usual. This difficult process is becoming easier with technologies that permit rapid gene sequencing and with sophisticated computer programs that can match up genetic patterns with their protein products.
An example of genetic modification is the introduction of a gene from the soil bacterium Bacillus thurigiensis into the genes of a crop plant the selected gene codes for a protein that is toxic to certain insects. The genetically modified plants then produce the protein, making them resistant to pests like the European Corn Borer or Cotton Boll Worm (the genes also protect potatoes and rice from destructive insects). By using this technology, the yield of plants is higher (since fewer are damaged by insects) and the use of insecticides against these pests can be reduced. Other pest-resistant GM crops on the market today have been engineered to contain genes that confer resistance to specific plant viruses.
Another example of genetic modification for food use is associated with the production of cheese. Traditionally, an enzyme preparation called rennet is added to milk. Rennet is isolated from the lining of calf stomachs it contains the enzyme chymosin, which causes milk protein (casein) to clump together into a solid gel, making hard cheese, like cheddar cheese. By the 1960s, the amount of rennet was insufficient to meet the increasing world-wide demand for cheese. So, cheese manufacturers turned to getting the enzyme from the stomachs of other animals or obtaining a similar enzyme from certain fungal strains (used for "rennetless" cheese that vegetarians preferred). Genetic engineering is the solution that worked the best. Bacteria were modified by inserting a gene that codes for producing chymosin identical to the enzyme obtained from calf it produces a better quality cheese than that produced using non-calf rennets. The technology was worked out in 1981 using bacteria, but relying instead on genetically modified food yeasts was soon found to be more productive. In 1988, chymosin was the first enzyme from a genetically-modified source to gain approval for use in food compared to the calf chymosin, its activity is more predictable and it has fewer impurities. Also, vegetarians have approved of these cheese products.
One of the best known of the GM food crops is the "roundup ready" soybean, introduced into commerce in 1997. These were developed by Monsanto, the same company that had produced the GM canola and that manufactures the herbicide (weed killer) called "Roundup," a form of glyphosphate. This genetic modification allows soybean farmers to get rid of weeds with Roundup while the soybeans are not adversely affected by it. Otherwise, soybean crop yields would be lowered by the growth of weeds, or less desirable chemicals would need to be used to control competition by weeds (glyphosphate is not carcinogenic, does not affect reproduction and development of animals, does not accumulate in the body, and is not acutely toxic in its dilute form). Today, 85% of the soybeans grown in the U.S. are GM soybeans. As the graph (below) displays, starting with that 1997 introduction, GM crop production took off.
Other crops grown commercially or field-tested include a sweet potato resistant to a virus that could decimate most of the African harvest rice with increased iron and vitamins that may alleviate chronic malnutrition in Asian countries and a variety of plants able to survive weather extremes. There are over 100 species of plants in the testing phase for potential commercial use of their genetic modifications.
While these GM crops are becoming increasingly relied upon, they still represent only a small fraction of all farming activity. In 2003, about 167 million acres (67.7 million hectares) were devoted to transgenic crops this is out of 1.5 billion total hectares, or about 4.5% of the world cropland. These crops were grown by about 7 million farmers in 18 countries, but mostly in the U.S., Argentina, Canada, Brazil, China, and South Africa. The main crops were the ones already mentioned, being herbicide-resistant and insect-resistant soybeans, corn, cotton, and canola.
In 2003, countries that grew 99% of the global transgenic crops were: the United States (63%), Argentina (21%), Canada (6%), Brazil (4%), and China (4%), and South Africa (1%) see the graph below, listing the acreage in millions for the countries indicated. Although growth of this enterprise will eventually plateau in industrialized countries, it will increase for decades in developing countries. It has been predicted that during the next few years we will see an exponential progress in GM product development as researchers gain access to genetic information and resources beyond the more limited scope of individual projects undertaken thus far.
Technologies for genetically modifying foods offer dramatic promise for meeting some areas of greatest challenge for the 21st century. Like all new technologies, they also pose some risks, both known and unknown. Controversies surrounding GM foods and crops commonly focus on human and environmental safety, labeling and consumer choice, intellectual property rights, ethics, food security, poverty reduction, and environmental conservation (see last page for a summary: "GM Foods: Benefits and Controversies").
10 Genetically Modified Animals You Might Not Know
Enviropig, also known as Frankenswine, is a type of pig which was genetically modified: it contains DNA from the mouse and E. Coli. So it can process and digest phosphorus better, and then it is unnecessary to feed them with additional phosphorus. This kind of pig is created for the current issue that normal pig manure contains high levels of phosphorus, so if it is used as fertilizer, this chemical gets into the water, leading to algae blooms and oxygen depletion as well as death of marine life. The enviropig won't need to be fed with phosphorus, so their manure has quite low level of it, thus they won't do harm to the marine animals.
When it comes to natural goods, flexible and strong spider silk is incredibly valuable. If we were able to make it on a larger scale, it would be useful for parachute cords, artificial ligaments, and everything in between. Nexia Biotechnologies announced in 2000 the creation of one of the genetically engineered animals to fix this problem. They engineered a goat which produces the protein found in spiders' webs in its milk. To do this, they inserted a dragline silk gene from spiders into goats. You can use the silk milk produced by the goats to create Biosteel, a web-like material.
AquaBounty made their contribution to the world' genetically modified animals in the form of a fast-growing salmon. This fish is actually able to grow twice as fast as typical fish, despite having the same odor, color, texture, and flavor of standard salmon. These Atlantic salmon were genetically engineered to add the growth hormone of Chinook salmon so they can produce the necessary growth hormone throughout the entire year. The hormone stays activated thanks to a gene of ocean pout, a fish that is eel-like. There are still debates, however, as to whether this fish is safe to eat. If the FDA approves them, they would not need a label indicating that these are genetically modified.
Cows are known for their high production of methane, the second largest factor for the greenhouse effect. Cows naturally produce methane due to their digestion process, specifically a bacterium that results from the cow diet of grass and hay, both of which are high in cellulose. Agriculture research scientists from the University of Alberta worked to identify this bacterium that is responsible for methane. Afterwards, they created cattle with 25 percent less production of methane compared to average cows.
Some mosquitoes were engineered as a way to fight malaria. This disease causes a million deaths annually as well as infecting additional 300 million people. These malaria fighting mosquitoes are able to resist the plasmodium parasite, which means that it is almost impossible for them to become infected with the disease. The thing, however, is that plasmodium parasites can evolve quickly, leading to some people wondering if we would be better off by killing mosquitoes.
To deal with this option, some scientists created sudden-death mosquitos which pass the relevant gene to their offspring. This gene means that the baby mosquitoes would die (naturally of old age) before reaching sexual maturity. The issue, however, is that without mosquitoes, the entire ecosystem would be affected with facing extinction of bats and other predators.
Glittering Gold Seahorses
You can actually buy a glittering gold seahorse if you really want to. Vietnamese scientists created this, the first of genetically modified animals originating from Vietnam. Scientists used the gene shooting method to insert a mixture of jellyfish proteins and gold dust into the eggs of a seahorse. While gold seahorses are pretty, gene shooting has many other implications, such as treating diabetes and other incurable diseases by replacement of problematic DNA within the body.
Mostly Male Tilapia
Over the years, tilapia have undergone genetic modifications to let them mature much faster, survive on a smaller quantity of food, and grow larger. Tilapia farmers, however, want to take this a step further and make male tilapia more common than female ones. This is because females "mouthbrood", which means they hold their eggs in their mouths over an extended period of time. During this time, they won't eat anything so they don't accidentally swallow the eggs, resulting in smaller fish. Because of mouthbrooding, tilapia farmers rather have males on their farms.
Scientists in Israel are responsible for this prototype, which is a featherless chicken. They are significantly cheaper to raise, more environmentally friendly, and don't require plucking, which saves time. The scientists say they bred a species which has naked neck with a standard broiler chicken. There are, however, some drawbacks. The feathers on chickens help protect them from harsh weather, parasites, and even overzealous cocks during mating.
The glow-in-the-dark rabbit is one of the genetically modified animals that stemmed from art. Eduard Kac uses genetic engineering for creating works of art that are alive. In May 2000, he introduced Alba, an albino rabbit that will glow fluorescent when in blue light, known as his "GFP bunny." The idea to create Alba has a public debate concerning animals with modified genes for research. He then took Alba home to be his pet. To create Alba, a French research institute injected fluorescent jellyfish protein in a rabbit egg which was fertilized. They never agreed for Kac to take Alba home and there were animal rights debates, but Alba died before the issue could be resolved.
The glow-in-the-dark cat was developed as a way to fight feline immunodeficiency virus (FIV), which is related to HIV and typically affects feral cats. American and Japanese scientists in 2011 inserted genes in cats to help resist FIV. In order to mark the cells more easily, they also inserted a green fluorescent protein and both genes transferred to feline eggs. This let the scientists examine how this resistant gene developed within the cats by examination under a microscope. The cats are always normal during the day, but sometimes glow at night.