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Category Archives: Genetic Engineering

Genetic Engineering | MSPCA-Angell

Posted: November 10, 2016 at 4:44 pm

The MSPCAbelieves scientists ability to clone animals, to alter the genetic makeup of an animal, and to transfer pieces of genetic material from one species to another raises serious concerns for animals and humans alike.

This pagewill explore issues related to genetic engineering, transgenic animals, and cloned animals. It will examine the implications of genetic engineering on human and animal welfare and will touch on some related moral and ethical concerns that our society has so far failed to completely address.

Definitions

Problems related to the physical and psychological well-being of cloned and transgenic animals, significant ethical concerns about the direct manipulation of genetic material, and questions about the value of life itself must all be carefully weighed against the potential benefits of genetic engineering for disease research, agricultural purposes, vaccine development, pharmaceutical products, and organ transplants.

Genetic engineering is, as yet, an imperfect science that yields imperfect results.

Changes in animal growth and development brought about by genetic engineering and cloning are less predictable, more rapid, and often more debilitating than changes brought about through the traditional process of selective breeding.

This is especially apparent with cloning. Success rates are incredibly low; on average, less than 5% of cloned embryos are born and survive.

Clones are created at a great cost to animals. The clones that are successful, as well as those that do not survive and the surrogates who carry them, suffer greatly.Many of the cloned animals that do survive are plagued by severe health problems.

Offspring suffer from severe birth defects such as Large Offspring Syndrome (LOS), in which the cloned offspring are significantly larger than normal fetuses; hydrops, a typically fatal condition in which the mother or the fetus swells with fluid; respiratory distress; developmental problems; malformed organs; musculoskeletal deformities; or weakened immune systems, to name only a few.

Additionally, surrogates are subjected to repeated invasive procedures to harvest their eggs, implant embryos, or due to the offsprings birth defects surgical intervention to deliver their offspring. All of these problems occur at much higher rates than for offspring produced via traditional breeding methods.

Cloning increases existing animal welfare and environmental concerns related to animal agriculture.

In 1996, the birth of the ewe, Dolly, marked the first successful cloning of a mammal from adult cells. At the time of her birth, the researchers who created Dolly acknowledged the inefficiency of the new technology: it took 277 attempts to create this one sheep, and of these, only 29 early embryos developed, and an even smaller number of these developed into live fetuses. In the end, Dolly was the sole surviving clone. She was euthanized in 2003 at just 6 years of age, about half as old as sheep are expected to live, and with health problems more common in older sheep.

Since Dollys creation, the process of cloning has not demonstrated great improvement in efficiency or rates of success. A 2003 review of cloning in cattle found that less than 5% of cloned embryos transferred into surrogate cows survived; a 2016 study showedno noticeable increase in efficiency, with the success rate being about 1%.

Currently, research is focused on cloning for agricultural purposes. Used alone, or in concert with genetic engineering, the objective is to clone the best stock to reproduce whole herds or flocks with desired uniform characteristics of a specific trait, such as fast growth, leaner meat, or higher milk production. Cloning is often pursued to produce animals that grow faster so they can be slaughtered sooner and to raise more animals in a smaller space.

For example, transgenic fish are engineered to grow larger at a faster rate and cows injected with genetically engineered products to increase their productivity. Another example of this is the use of the genetically engineered drug, bovine growth hormone (BGH or BST) to increase milk production in dairy cows. This has also been associated with increased cases of udder disease, spontaneous abortion, lameness, and shortened lifespan. The use of BGH is controversial; many countries (such as Canada, Japan, Australia, and countries in the EU) do not allow it, and many consumers try to avoid it.A rise in transgenic animals used for agriculture will only exacerbate current animal welfare and environmental concerns with existing intensive farming operations.(For more information on farming and animal welfare, visit the MSPCAs Farm Animal Welfare page.)

Much remains unknown about thepotential environmental impacts of widespread cloning of animals. The creation of genetically identical animals leads to concerns about limited agricultural animal gene pools. The effects of creating uniform herds of animals and the resulting loss of biodiversity, have significant implications for the environment and for the ability of cloned herds to withstand diseases. This could make an impact on the entireagriculture industry and human food chain.

These issues became especiallyconcerning when, in 2008, the Federal Drug Administration not only approved the sale of meat from the offspring of cloned animals, but also did not require that it be labeled as such. There have been few published studies that examine the composition of milk, meat, or eggs from cloned animals or their progeny, including the safety of eating those products. The health problems associated with cloned animals, particularly those that appear healthy but have concealed illnesses or problems that appear unexpectedly later in life, could potentially pose risks to the safety of the food products derived from those animals.

Genetically Engineered Pets

Companion animals have also been cloned. The first cloned cat, CC, was created in 2001. CCs creation marked the beginning of the pet cloning industry, in which pet owners could pay to bank DNA from their companion dogs and cats to be cloned in the future. In 2005, the first cloned dog was created; later, the first commercially cloned dog followed at a cost of $50,000. Many consumers assume that cloning will produce a carbon copy of their beloved pet, but this is not the case. Even though the animals are genetically identical, they often do not resemble each other physically or behaviorally.

To date, the pet cloning industry has not been largely successful. However, efforts to make cloning a successful commercial venture are still being put forth.RBio (formerly RNL Bio), a Korean biotechnology company, planned to create a research center that would produce 1,000 cloned dogs annually by 2013. However, RBio, considered a black market cloner, failed to make any significant strides in itscloning endeavors and seems to have been replaced by other companies, such as South Korean-based Sooam Biotech, now the worlds leader in commercial pet cloning. Since 2006, Sooam has cloned over 800 dogs, in addition to other animals, such as cattle and pigs, for breed preservation and medical research.

While South Korean animal cloning expands, the interest in companion animal cloning in the United States continues to remain low. In 2009, the American company BioArts ceased its dog cloning services and ended its partnership with Sooam, stating in a press release that cloning procedures were still underdeveloped and that the cloning market itself was weak and unethical. Companion animal cloning causes concern not only because of the welfare issues inherent in the cloning process, but also because of its potential to contribute to pet overpopulation problem in the US, as millions of animals in shelters wait for homes.

Cloning and Medical Research

Cloning is also used to produce copies of transgenic animals that have been created to mimic certain human diseases. The transgenic animals are created, then cloned, producing a supply of animals for biomedical testing.

A 1980 U.S. Supreme Court decision to permit the patenting of a microorganism that could digest crude oil had a great impact on animal welfare and genetic engineering. Until that time, the U.S. Patent Office had prohibited the patenting of living organisms. However, following the Supreme Court decision, the Patent Office interpreted this ruling to extend to the patenting of all higher life forms, paving the way for a tremendous explosion of corporate investment in genetic engineering research.

In 1988, the first animal patent was issued to Harvard University for the Oncomouse, a transgenic mouse genetically modified to be more prone to develop cancers mimicking human disease. Since then, millions of transgenic mice have been produced. Transgenic rats, rabbits, monkeys, fish, chickens, pigs, sheep, goats, cows, horses, cats, dogs, and other animals have also been created.

Both expected and unexpected results occur in the process of inserting new genetic material into an egg cell. Defective offspring can suffer from chromosomal abnormalities that can cause cancer, fatal bleeding disorders, inability to reproduce, early uterine death, lack of ability to nurse, and such diseases as arthritis, diabetes, liver disease, and kidney disease.

The production of transgenic animals is of concern because genetic engineering is often used to create animals with diseases that cause intense suffering. Among the diseases that can be produced in genetically engineered research mice are diabetes, cancer, cystic fibrosis, sickle-cell anemia, Huntingtons disease, Alzheimers disease, and a rare but severe neurological condition called Lesch-Nyhansyndromethat causes the sufferer to self-mutilate. Animals carrying the genes for these diseases can suffer for long periods of time, both in the laboratory and while they are kept on the shelf by laboratory animal suppliers.

Another reason for the production of transgenic animals is pharming, in which sheep and goats are modified to produce pharmaceuticals in their milk. In 2009, the first drug produced by genetically engineered animals was approved by the FDA. The drug ATryn, used to prevent fatal blood clots in humans, is derived from goats into which a segment of human DNA has been inserted, causing them to produce an anticoagulant protein in their milk. This marks the first time a drug has been manufactured from a herd of animals created specifically to produce a pharmaceutical.

A company has also manufactured a drug produced in the milk of transgenic rabbits to treat a dangerous tissue swelling caused by a human protein deficiency. Yet another pharmaceutical manufacturer, PharmAnthene, was funded by the US Department of Defense to develop genetically engineered goats whose milk produces proteins used in a drug to treat nerve gas poisoning. The FDA also approved a drug whose primary proteins are also found in the milk of genetically engineered goats, who are kept at a farm in Framingham, Massachusetts. Additionally, a herd of cattle was recently developed that produces milk containing proteins that help to treat human emphysema. These animals are essentially used as pharmaceutical-production machines to manufacture only those substances they were genetically modified to produce; they are not used as part of the normal food supply chain for items such as meat or milk.

The transfer of animal tissues from one species to another raises potentially serious health issues for animals and humans alike.

Some animals are also genetically modified to produce tissues and organs to be used for human transplant purposes (xenotransplantation). Much effort is being focused in this area as the demand for human organs for transplantation far exceeds the supply, with pigs the current focus of this research. While efforts to date have been hampered by a pig protein that can cause organ rejection by the recipients immune system, efforts are underway to develop genetically modified swine with a human protein that would mitigate the chance of organ rejection.

Little is known about the ways in which diseases can be spread from one species to another, raising concerns for both animals and people, and calling into question the safety of using transgenic pigs to supply organs for human transplant purposes. Scientists have identified various viruses common in the heart, spleen, and kidneys of pigs that could infect human cells. In addition, new research is shedding light on particles called prions that, along with viruses and bacteria, may transmit fatal diseases between animals and from animals to humans.

Acknowledging the potential for transmission of viruses from animals to humans, the National Institutes of Health, a part of the U.S. Department of Health and Human Services,issued a moratorium in 2015 onxenotransplantation until the risks are better understood, ceasing funding until more research has been carried out. With the science of genetic engineering, the possibilities are endless, but so too are the risks and concerns.

Genetic engineering research has broad ethical and moral ramifications with few established societal guidelines.

While biotechnology has been quietly revolutionizing the science for decades, public debate in the United Statesover the moral, ethical, and physical effects of this research has been insufficient. To quote Colorado State University Philosopher Bernard Rollin, We cannot control technology if we do not understand it, and we cannot understand it without a careful discussion of the moral questions to which it gives rise.

Research into non-animal methods of achieving some of the same goals looks promising.

Researchers in the U.S. and elsewhere have found ways togenetically engineer cereal grains to produce human proteins. One example of this, developed in the early 2000s, is a strain of rice that can produce a human protein used to treat cystic fibrosis. Wheat, corn, and barley may also be able to be used in similar ways at dramatically lower financial and ethical costs than genetically engineering animals for this purpose.

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Genetic Engineering | MSPCA-Angell

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What is genetic engineering? – Definition from WhatIs.com

Posted: November 10, 2016 at 4:44 pm

Genetic engineering is the deliberate, controlled manipulation of the genes in an organism with the intent of making that organism better in some way. This is usually done independently of the natural reproductive process. The result is a so-called genetically modified organism (GMO). To date, most of the effort in genetic engineering has been focused on agriculture.

Proponents of genetic engineering claim that it has numerous benefits, including the production of food-bearing plants that are resistant to extreme weather and adverse climates, insect infestations, disease, molds, and fungi. In addition, it may be possible to reduce the amount of plowing necessary in the farming process, thereby saving energy and minimizing soil erosion. A major motivation is the hope of producing abundant food at low cost to reduce world hunger, both directly (by feeding GMOs to human beings) and indirectly (by feeding GMOs to livestock and fish, which can in turn be fed to humans).

Genetic engineering carries potential dangers, such as the creation of new allergens and toxins, the evolution of new weeds and other noxious vegetation, harm to wildlife, and the creation of environments favorable to the proliferation of molds and fungi (ironically, in light of the purported advantage in that respect). Some scientists have expressed concern that new disease organisms and increased antibiotic resistance could result from the use of GMOs in the food chain.

The darkest aspect of genetic engineering is the possibility that a government or institution might undertake to enhance human beings by means of genetic engineering. Some see the possibility of using this technology to create biological weapons.

Genetic engineering is also known as genetic modification.

This was last updated in May 2007

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Genetic Engineering – The New York Times

Posted: November 10, 2016 at 4:44 pm

Latest Articles

A cotton farmer in India says they have greatly increased his yield. The Union of Concerned Scientists urges better crop management methods instead.

Higher yields with less pesticides was the sales pitch for genetically modified seeds. But that has not proved to be the outcome in the United States.

By DANNY HAKIM

A new survey shows distrust of scientists, a suspicion about claims of progress and discomfort with the idea of meddling with human abilities.

By GINA KOLATA

The bill would require companies to indicate that foods have genetically engineered ingredients, but disagreement remains over how that would be done.

By STEPHANIE STROM

The study was testing the use of genetically engineered cells as a treatment for cancer, which had shown promising earlier results.

The bill would set a national standard for labeling G.M.O. foods, though critics say the system would not be tough enough.

By STEPHANIE STROM

A proposed law would make it unnecessarily difficult to check a label, by requiring the scanning of electronic codes in the store.

By THE EDITORIAL BOARD

As of Friday, nearly all food labels in the state must disclose when products include genetically engineered ingredients.

By STEPHANIE STROM

The worlds top scientists say opponents of genetically modified foods are standing in the way of nutrition for people around the world.

By NIRAJ CHOKSHI

A technique to change or eliminate entire populations of organisms could be used against virus-carrying mosquitoes. It could also have unintended consequences.

By AMY HARMON

Residents there heard a proposal Monday from an M.I.T. scientist to use genetically engineered mice to stop the spread of the tick-borne disease.

By AMY HARMON

A common bacterium contains molecules that target RNA, not DNA. If it can be harnessed for use in humans, the process may lead to new forms of bioengineering.

By CARL ZIMMER

The formal announcement of the plans, which leaked last month, seeks to raise $100 million this year. The total price tag could exceed $1 billion.

By ANDREW POLLACK

One of the scientists credited with starting the gene editing revolution discusses her landmark discovery and how science has driven her.

By GINA KOLATA

Ritual, a start-up, is introducing a multivitamin that is vegan, mostly free of genetically engineered ingredients and tailored to todays diets.

By STEPHANIE STROM

The transaction, if consummated, would create an industry giant whose products include pain medications, genetically modified crops and pesticides.

By MICHAEL J. de la MERCED and CHAD BRAY

Without disclosing details, Monsanto said its board was reviewing a proposal that would create a giant with a combined annual revenue of $67 billion.

By MICHAEL J. de la MERCED

The report from the National Academies of Sciences, Engineering and Medicine is not expected to end the highly polarized debate over the technology.

By ANDREW POLLACK

Bioengineered food products are safe. So why do we try to hide the facts about them?

By JASON KELLY

The project poses ethical issues about whether humans could be created without parents.

By ANDREW POLLACK

A cotton farmer in India says they have greatly increased his yield. The Union of Concerned Scientists urges better crop management methods instead.

Higher yields with less pesticides was the sales pitch for genetically modified seeds. But that has not proved to be the outcome in the United States.

By DANNY HAKIM

A new survey shows distrust of scientists, a suspicion about claims of progress and discomfort with the idea of meddling with human abilities.

By GINA KOLATA

The bill would require companies to indicate that foods have genetically engineered ingredients, but disagreement remains over how that would be done.

By STEPHANIE STROM

The study was testing the use of genetically engineered cells as a treatment for cancer, which had shown promising earlier results.

The bill would set a national standard for labeling G.M.O. foods, though critics say the system would not be tough enough.

By STEPHANIE STROM

A proposed law would make it unnecessarily difficult to check a label, by requiring the scanning of electronic codes in the store.

By THE EDITORIAL BOARD

As of Friday, nearly all food labels in the state must disclose when products include genetically engineered ingredients.

By STEPHANIE STROM

The worlds top scientists say opponents of genetically modified foods are standing in the way of nutrition for people around the world.

By NIRAJ CHOKSHI

A technique to change or eliminate entire populations of organisms could be used against virus-carrying mosquitoes. It could also have unintended consequences.

By AMY HARMON

Residents there heard a proposal Monday from an M.I.T. scientist to use genetically engineered mice to stop the spread of the tick-borne disease.

By AMY HARMON

A common bacterium contains molecules that target RNA, not DNA. If it can be harnessed for use in humans, the process may lead to new forms of bioengineering.

By CARL ZIMMER

The formal announcement of the plans, which leaked last month, seeks to raise $100 million this year. The total price tag could exceed $1 billion.

By ANDREW POLLACK

One of the scientists credited with starting the gene editing revolution discusses her landmark discovery and how science has driven her.

By GINA KOLATA

Ritual, a start-up, is introducing a multivitamin that is vegan, mostly free of genetically engineered ingredients and tailored to todays diets.

By STEPHANIE STROM

The transaction, if consummated, would create an industry giant whose products include pain medications, genetically modified crops and pesticides.

By MICHAEL J. de la MERCED and CHAD BRAY

Without disclosing details, Monsanto said its board was reviewing a proposal that would create a giant with a combined annual revenue of $67 billion.

By MICHAEL J. de la MERCED

The report from the National Academies of Sciences, Engineering and Medicine is not expected to end the highly polarized debate over the technology.

By ANDREW POLLACK

Bioengineered food products are safe. So why do we try to hide the facts about them?

By JASON KELLY

The project poses ethical issues about whether humans could be created without parents.

By ANDREW POLLACK

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Genetic Engineering - The New York Times

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Pros and Cons of Genetic Engineering | HRFnd

Posted: November 10, 2016 at 4:44 pm

Manipulation of genes in natural organisms, such as plants, animals, and even humans, is considered genetic engineering. This is done using a variety of different techniques like molecular cloning. These processes can cause dramatic changes in the natural makeup and characteristic of the organism. There are benefits and risks associated with genetic engineering, just like most other scientific practices.

Genetic engineering offers benefits such as:

1. Better Flavor, Growth Rate and Nutrition Crops like potatoes, soybeans and tomatoes are now sometimes genetically engineered in order to improve size, crop yield, and nutritional values of the plants. These genetically engineered crops also possess the ability to grow in lands that would normally not be suitable for cultivation.

2. Pest-resistant Crops and Extended Shelf Life Engineered seeds can resist pests and having a better chance at survival in harsh weather. Biotechnology could be in increasing the shelf life of many foods.

3. Genetic Alteration to Supply New Foods Genetic engineering can also be used in producing completely new substances like proteins or other nutrients in food. This may up the benefits they have for medical uses.

4. Modification of the Human DNA Genes that are responsible for unique and desirable qualities in the human DNA can be exposed and introduced into the genes of another person. This changes the structural elements of a persons DNA. The effects of this are not know.

The following are the issues that genetic engineering can trigger:

1. May Hamper Nutritional Value Genetic engineering on food also includes the infectivity of genes in root crops. These crops might supersede the natural weeds. These can be dangerous for the natural plants. Unpleasant genetic mutations could result to an increased allergy occurrence of the crop. Some people believe that this science on foods can hamper the nutrients contained by the crops although their appearance and taste were enhanced.

2. May Introduce Risky Pathogens Horizontal gene shift could give increase to other pathogens. While it increases the immunity against diseases among the plants, the resistant genes can be transmitted to harmful pathogens.

3. May Result to Genetic Problems Gene therapy on humans can end to some side effects. While relieving one problem, the treatment may cause the onset of another issue. As a single cell is liable for various characteristics, the cell isolation process will be responsible for one trait will be complicated.

4. Unfavorable to Genetic Diversity Genetic engineering can affect the diversity among the individuals. Cloning might be unfavorable to individualism. Furthermore, such process might not be affordable for poor. Hence, it makes the gene therapy impossible for an average person.

Genetic engineering might work excellently but after all, it is a kind of process that manipulates the natural. This is altering something which has not been created originally by humans. What can you say about this?

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Genetic Engineering and GM Crops – Pocket K | ISAAA.org

Posted: November 10, 2016 at 4:44 pm

Over the last 50 years, the field of genetic engineering has developed rapidly due to the greater understanding of deoxyribonucleic acid (DNA) as the chemical double helix code from which genes are made. The term genetic engineering is used to describe the process by which the genetic makeup of an organism can be altered using recombinant DNA technology. This involves the use of laboratory tools to insert, alter, or cut out pieces of DNA that contain one or more genes of interest.

Developing plant varieties expressing good agronomic characteristics is the ultimate goal of plant breeders. With conventional plant breeding, however, there is little or no guarantee of obtaining any particular gene combination from the millions of crosses generated. Undesirable genes can be transferred along with desirable genes; or, while one desirable gene is gained, another is lost because the genes of both parents are mixed together and re-assorted more or less randomly in the offspring. These problems limit the improvements that plant breeders can achieve.

In contrast, genetic engineering allows the direct transfer of one or just a few genes of interest, between either closely or distantly related organisms to obtain the desired agronomic trait (Figure 1). Not all genetic engineering techniques involve inserting DNA from other organisms. Plants may also be modified by removing or switching off their own particular genes.

Source: Agricultural Biotechnology (A Lot More than Just GM Crops). http://www.isaaa.org/resources/publications/agricultural_biotechnology/download/.

Genes are molecules of DNA that code for distinct traits or characteristics. For instance, a particular gene sequence is responsible for the color of a flower or a plants ability to fight a disease or thrive in extreme environment.

The sharing of DNA among living forms is well documented as a natural phenomenon. For thousands of years, genes have moved from one organism to another. For example, Agrobacterium tumefaciens, a soil bacterium known as natures own genetic engineer, has the natural ability to genetically engineer plants. It causes crown gall disease in a wide range of broad-leaved plants, such as apple, pear, peach, cherry, almond, raspberry, and roses. The disease gains its name from the large tumor-like swellings (galls) that typically occur at the crown of the plant, just above soil level. Basically, the bacterium transfers part of its DNA to the plant, and this DNA integrates into the plants genome, causing the production of tumors and associated changes in plant metabolism.

Genetic engineering techniques are used only when all other techniques have been exhausted, i.e. when the trait to be introduced is not present in the germplasm of the crop; the trait is very difficult to improve by conventional breeding methods; and when it will take a very long time to introduce and/or improve such trait in the crop by conventional breeding methods (see Figure 2). Crops developed through genetic engineering are commonly known as transgenic crops or genetically modified (GM) crops.

Modern plant breeding is a multi-disciplinary and coordinated process where a large number of tools and elements of conventional breeding techniques, bioinformatics, molecular genetics, molecular biology, and genetic engineering are utilized and integrated.

Figure 2: Modern Plant Breeding

Source: DANIDA, 2002.

Although there are many diverse and complex techniques involved in genetic engineering, its basic principles are reasonably simple. There are five major steps in the development of a genetically engineered crop. But for every step, it is very important to know the biochemical and physiological mechanisms of action, regulation of gene expression, and safety of the gene and the gene product to be utilized. Even before a genetically engineered crop is made available for commercial use, it has to pass through rigorous safety and risk assessment procedures.

The first step is the extraction of DNA from the organism known to have the trait of interest. The second step is gene cloning, which will isolate the gene of interest from the entire extracted DNA, followed by mass-production of the cloned gene in a host cell. Once it is cloned, the gene of interest is designed and packaged so that it can be controlled and properly expressed once inside the host plant. The modified gene will then be mass-produced in a host cell in order to make thousands of copies. When the gene package is ready, it can then be introduced into the cells of the plant being modified through a process called transformation. The most common methods used to introduce the gene package into plant cells include biolistic transformation (using a gene gun) or Agrobacterium-mediated transformation. Once the inserted gene is stable, inherited, and expressed in subsequent generations, then the plant is considered a transgenic. Backcross breeding is the final step in the genetic engineering process, where the transgenic crop is crossed with a variety that possesses important agronomic traits, and selected in order to obtain high quality plants that express the inserted gene in a desired manner.

The length of time in developing transgenic plant depends upon the gene, crop species, available resources, and regulatory approval. It may take 6-15 years before a new transgenic hybrid is ready for commercial release.

Transgenic crops have been planted in different countries for twenty years, starting from 1996 to 2015. About 179.7 million hectares was planted in 2015 to transgenic crops with high market value, such as herbicide tolerant soybean, maize, cotton, and canola; insect resistant maize, cotton, potato, and rice; and virus resistant squash and papaya. With genetic engineering, more than one trait can be incorporated or stacked into a plant. Transgenic crops with combined traits are also available commercially. These include herbicide tolerant and insect resistant maize, soybean and cotton.

To date, commercial GM crops have delivered benefits in crop production, but there are also a number of products in the pipeline which will make more direct contributions to food quality, environmental benefits, pharmaceutical production, and non-food crops. Examples of these products include: rice with higher levels of iron and beta-carotene (an important micronutrient which is converted to vitamin A in the body); long life banana that ripens faster on the tree and can therefore be harvested earlier; tomatoes with high levels of flavonols, which are powerful antioxidants; arsenic-tolerant plants; edible vaccines from fruit and vegetables; and low lignin trees for paper making.

*August 2016

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Human Genetic Engineering – Popular Issues

Posted: October 29, 2016 at 6:45 am

Human Genetic Engineering - A Hot Issue! Human genetic engineering is a hot topic in the legislative and executive branches of the U.S. government. Time will tell how committed the United States will be regarding the absolute ban on human cloning.

Human Genetic Engineering - Position of the U.S. Government Human genetic engineering has made its way to Capitol Hill. On July 31, 2001, the House of Representatives passed a bill which would ban human cloning, not only for reproduction, but for medical research purposes as well. The Human Cloning Prohibition Act of 2001, sponsored by Rep. Weldon (R-fL) and co-sponsored by over 100 Representatives, passed by a bipartisan vote of 265-to-162. The Act makes it unlawful to: "1) perform or attempt to perform human cloning, 2) participate in an attempt to perform cloning, or 3) ship or receive the product of human cloning for any purpose." The Act also imposes penalties of up to 10 years imprisonment and no less than $1,000,000 for breaking the law. The same bill, sponsored by Sen. Brownback (R-kS), is currently being debated in the Senate.

The White House also opposes "any and all attempts to clone a human being; [they] oppose the use of human somatic cell nuclear transfer cloning techniques either to assist human reproduction or to develop cell or tissue-based therapies."

Human Genetic Engineering - The Problems There are many arguments against human genetic engineering, including the established safety issues, the loss of identity and individuality, and human diversity. With therapeutic cloning, not only do the above issues apply, but you add all the moral and religious issues related to the willful killing of human embryos. Maybe the greatest concern of all is that man would become simply another man-made thing. As with any other man-made thing, the designer "stands above [its design], not as an equal but as a superior, transcending it by his will and creative prowess." The cloned child will be dehumanized. (See, Leon Kass, Preventing a Brave New World: Why we should ban human cloning now, New Republic Online, May 21, 2001.)

Human Genetic Engineering - A Final Thought Human genetic engineering leads to man usurping God as the almighty creator and designer of life. No longer will a child be considered a blessing from God, but rather, a product manufactured by a scientist. Man will be a created being of man. However, man was always intended to be a created being of God, in His absolute love, wisdom and glory.

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Explore More: Genetic Engineering – iptv.org

Posted: October 29, 2016 at 6:45 am

Watch the full show online! Visit the Explore More Genetic Engineering video page...

Would you want to clone your pet? Would you change your child's eye color? Do you care if your strawberry contains a gene for fish?

Explore More: Genetic Engineering tells you the story, gives you the facts, and then takes a closer look to help you unravel the core issues. Take a look at and interact with the content. Discuss what you learn with other people, form your own opinion on the subjects, but always keep an open mind.

As you go through this site, think about how genetic engineering is changing the way we live. This is a fascinating area that deserves our attention. Decisions and choices we make in our lifetime will affect how and why genetic engineering is used.

Investigate Explore More Teacher Resources WebQuests, Web links, lesson plans, teaching strategies, discussion questions, standards, and project goals help you leverage Explore More content to help student achievement and motivation. Get your students thinking with this useful collection of tools and tips! Find out more.

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Recent Articles | Genetic Engineering | The Scientist …

Posted: October 20, 2016 at 1:44 am

Most Recent

Tweaks to a transformation protocol in 1986 cemented the little plant's mighty role in plant genetics research.

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Other government authorities have yet to evaluate a proposal aimed at reducing populations of Zika-carrying insects in Florida.

3 Comments

Researchers engineer bacteria that deliver an anti-tumor toxin in mice before self-destructing.

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A National Academiesled analysis evaluates the impacts of genetically engineered cropsand calls for updated regulations.

1 Comment

Researchers use a gene editor to introduce an allele that eliminates the horned traitand thus, the need for an expensive and painful process of dehorningin dairy cows.

2 Comments

Monkeys genetically engineered with multiple copies of an autism-linked human gene display some autism-like behaviors, scientists show.

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Genetically modified bacteria that dont survive unless given an unnatural amino acid could serve as a new control measure to protect wild organisms and ecosystems against accidental release.

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By Kerry Grens | December 24, 2015

The Scientists choice of major improvements in imaging, optogenetics, single-cell analyses, and CRISPR

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By Kerry Grens | December 21, 2015

The first two bulls genetically engineered to lack horns arrived at the University of California, Davis, for breeding.

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By Kate Yandell | December 7, 2015

Kill switches ensure that genetically engineered bacteria survive only in certain environmental conditions.

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UNL’s AgBiosafety for Educators

Posted: September 28, 2016 at 5:46 pm

What is genetic engineering? Genetic engineering is the process of manually adding new DNA to an organism. The goal is to add one or more new traits that are not already found in that organism. Examples of genetically engineered (transgenic) organisms currently on the market include plants with resistance to some insects, plants that can tolerate herbicides, and crops with modified oil content.

Understanding Genetic Engineering: Basic Biology To understand how genetic engineering works, there are a few key biology concepts that must be understood.

Small segments of DNA are called genes. Each gene holds the instructions for how to produce a single protein. This can be compared to a recipe for making a food dish. A recipe is a set of instructions for making a single dish.

An organism may have thousands of genes. The set of all genes in an organism is called a genome. A genome can be compared to a cookbook of recipes that makes that organism what it is. Every cell of every living organism has a cookbook.

CONCEPT #2: Why are proteins important? Proteins do the work in cells. They can be part of structures (such as cell walls, organelles, etc). They can regulate reactions that take place in the cell. Or they can serve as enzymes, which speed-up reactions. Everything you see in an organism is either made of proteins or the result of a protein action.

How is genetic engineering done? Genetic engineering, also called transformation, works by physically removing a gene from one organism and inserting it into another, giving it the ability to express the trait encoded by that gene. It is like taking a single recipe out of a cookbook and placing it into another cookbook.

1) First, find an organism that naturally contains the desired trait.

2) The DNA is extracted from that organism. This is like taking out the entire cookbook.

3) The one desired gene (recipe) must be located and copied from thousands of genes that were extracted. This is called gene cloning.

4) The gene may be modified slightly to work in a more desirable way once inside the recipient organism.

5) The new gene(s), called a transgene is delivered into cells of the recipient organism. This is called transformation. The most common transformation technique uses a bacteria that naturally genetically engineer plants with its own DNA. The transgene is inserted into the bacteria, which then delivers it into cells of the organism being engineered. Another technique, called the gene gun method, shoots microscopic gold particles coated with copies of the transgene into cells of the recipient organism. With either technique, genetic engineers have no control over where or if the transgene inserts into the genome. As a result, it takes hundreds of attempts to achieve just a few transgenic organisms.

6) Once a transgenic organism has been created, traditional breeding is used to improve the characteristics of the final product. So genetic engineering does not eliminate the need for traditional breeding. It is simply a way to add new traits to the pool.

How does genetic engineering compare to traditional breeding? Although the goal of both genetic engineering and traditional plant breeding is to improve an organisms traits, there are some key differences between them.

While genetic engineering manually moves genes from one organism to another, traditional breeding moves genes through mating, or crossing, the organisms in hopes of obtaining offspring with the desired combination of traits.

genetic engineering

Using the recipe analogy, traditional breeding is like taking two cookbooks and combining every other recipe from each into one cookbook. The product is a new cookbook with half of the recipes from each original book. Therefore, half of the genes in the offspring of a cross come from each parent.

Traditional breeding is effective in improving traits, however, when compared with genetic engineering, it does have disadvantages. Since breeding relies on the ability to mate two organisms to move genes, trait improvement is basically limited to those traits that already exist within that species. Genetic engineering, on the other hand, physically removes the genes from one organism and places them into the other. This eliminates the need for mating and allows the movement of genes between organisms of any species. Therefore, the potential traits that can be used are virtually unlimited.

Breeding is also less precise than genetic engineering. In breeding, half of the genes from each parent are passed on to the offspring. This may include many undesirable genes for traits that are not wanted in the new organism. Genetic engineering, however, allows for the movement of a single, or a few, genes.

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Genetic Engineering – BiologyMad

Posted: September 28, 2016 at 5:46 pm

Genetic Engineering

Genetic engineering, also known as recombinant DNA technology, means altering the genes in a living organism to produce a Genetically Modified Organism (GMO) with a new genotype. Various kinds of genetic modification are possible: inserting a foreign gene from one species into another, forming a transgenic organism; altering an existing gene so that its product is changed; or changing gene expression so that it is translated more often or not at all.

Genetic engineering is a very young discipline, and is only possible due to the development of techniques from the 1960s onwards. Watson and Crick have made these techniques possible from our greater understanding of DNA and how it functions following the discovery of its structure in 1953. Although the final goal of genetic engineering is usually the expression of a gene in a host, in fact most of the techniques and time in genetic engineering are spent isolating a gene and then cloning it. This table lists the techniques that we shall look at in detail.

1

cDNA

To make a DNA copy of mRNA

2

To cut DNA at specific points, making small fragments

3

DNA Ligase

To join DNA fragments together

4

Vectors

To carry DNA into cells and ensure replication

5

Plasmids

Common kind of vector

6

Gene Transfer

To deliver a gene to a living cells

7

Genetic Markers

To identify cells that have been transformed

8

To make exact copies of bacterial colonies on an agar plate

9

PCR

To amplify very small samples of DNA

10

DNA probes

To identify and label a piece of DNA containing a certain sequence

11

Shotgun *

To find a particular gene in a whole genome

12

Antisense genes *

To stop the expression of a gene in a cell

13

Gene Synthesis

To make a gene from scratch

14

Electrophoresis

To separate fragments of DNA

* Additional information that is not directly included in AS Biology. However it can help to consolidate other techniques.

Complementary DNA (cDNA) is DNA made from mRNA. This makes use of the enzyme reverse transcriptase, which does the reverse of transcription: it synthesises DNA from an RNA template. It is produced naturally by a group of viruses called the retroviruses (which include HIV), and it helps them to invade cells. In genetic engineering reverse transcriptase is used to make an artificial gene of cDNA as shown in this diagram.

Complementary DNA has helped to solve different problems in genetic engineering:

It makes genes much easier to find. There are some 70 000 genes in the human genome, and finding one gene out of this many is a very difficult (though not impossible) task. However a given cell only expresses a few genes, so only makes a few different kinds of mRNA molecule. For example the b cells of the pancreas make insulin, so make lots of mRNA molecules coding for insulin. This mRNA can be isolated from these cells and used to make cDNA of the insulin gene.

These are enzymes that cut DNA at specific sites. They are properly called restriction endonucleases because they cut the bonds in the middle of the polynucleotide chain. Some restriction enzymes cut straight across both chains, forming blunt ends, but most enzymes make a staggered cut in the two strands, forming sticky ends.

The cut ends are sticky because they have short stretches of single-stranded DNA with complementary sequences. These sticky ends will stick (or anneal) to another piece of DNA by complementary base pairing, but only if they have both been cut with the same restriction enzyme. Restriction enzymes are highly specific, and will only cut DNA at specific base sequences, 4-8 base pairs long, called recognition sequences.

Restriction enzymes are produced naturally by bacteria as a defence against viruses (they restrict viral growth), but they are enormously useful in genetic engineering for cutting DNA at precise places ("molecular scissors"). Short lengths of DNA cut out by restriction enzymes are called restriction fragments. There are thousands of different restriction enzymes known, with over a hundred different recognition sequences. Restriction enzymes are named after the bacteria species they came from, so EcoR1 is from E. coli strain R, and HindIII is from Haemophilis influenzae.

This enzyme repairs broken DNA by joining two nucleotides in a DNA strand. It is commonly used in genetic engineering to do the reverse of a restriction enzyme, i.e. to join together complementary restriction fragments.

The sticky ends allow two complementary restriction fragments to anneal, but only by weak hydrogen bonds, which can quite easily be broken, say by gentle heating. The backbone is still incomplete.

DNA ligase completes the DNA backbone by forming covalent bonds. Restriction enzymes and DNA ligase can therefore be used together to join lengths of DNA from different sources.

In biology a vector is something that carries things between species. For example the mosquito is a disease vector because it carries the malaria parasite into humans. In genetic engineering a vector is a length of DNA that carries the gene we want into a host cell. A vector is needed because a length of DNA containing a gene on its own wont actually do anything inside a host cell. Since it is not part of the cells normal genome it wont be replicated when the cell divides, it wont be expressed, and in fact it will probably be broken down pretty quickly. A vector gets round these problems by having these properties:

It is big enough to hold the gene we want (plus a few others), but not too big.

It is circular (or more accurately a closed loop), so that it is less likely to be broken down (particularly in prokaryotic cells where DNA is always circular).

It contains control sequences, such as a replication origin and a transcription promoter, so that the gene will be replicated, expressed, or incorporated into the cells normal genome.

It contain marker genes, so that cells containing the vector can be identified.

Many different vectors have been made for different purposes in genetic engineering by modifying naturally-occurring DNA molecules, and these are now available off the shelf. For example a cloning vector contains sequences that cause the gene to be copied (perhaps many times) inside a cell, but not expressed. An expression vector contains sequences causing the gene to be expressed inside a cell, preferably in response to an external stimulus, such as a particular chemical in the medium. Different kinds of vector are also available for different lengths of DNA insert:

Type of vector

Max length of DNA insert

10 kbp

Virus or phage

30 kbp

Bacterial Artificial Chromosome (BAC)

500 kbp

Plasmids are by far the most common kind of vector, so we shall look at how they are used in some detail. Plasmids are short circular bits of DNA found naturally in bacterial cells. A typical plasmid contains 3-5 genes and there are usually around 10 copies of a plasmid in a bacterial cell. Plasmids are copied separately from the main bacterial DNA when the cell divides, so the plasmid genes are passed on to all daughter cells. They are also used naturally for exchange of genes between bacterial cells (the nearest they get to sex), so bacterial cells will readily take up a plasmid. Because they are so small, they are easy to handle in a test tube, and foreign genes can quite easily be incorporated into them using restriction enzymes and DNA ligase.

One of the most common plasmids used is the R-plasmid (or pBR322). This plasmid contains a replication origin, several recognition sequences for different restriction enzymes (with names like PstI and EcoRI), and two marker genes, which confer resistance to different antibiotics (ampicillin and tetracycline).

The diagram below shows how DNA fragments can be incorporated into a plasmid using restriction and ligase enzymes. The restriction enzyme used here (PstI) cuts the plasmid in the middle of one of the markergenes (well see why this is useful later). The foreign DNA anneals with the plasmid and is joined covalently by DNA ligase to form a hybrid vector (in other words a mixture or hybrid of bacterial and foreign DNA). Several other products are also formed: some plasmids will simply re-anneal with themselves to re-form the original plasmid, and some DNA fragments will join together to form chains or circles. Theses different products cannot easily be separated, but it doesnt matter, as the marker genes can be used later to identify the correct hybrid vector.

Vectors containing the genes we want must be incorporated into living cells so that they can be replicated or expressed. The cells receiving the vector are called host cells, and once they have successfully incorporated the vector they are said to be transformed. Vectors are large molecules which do not readily cross cell membranes, so the membranes must be made permeable in some way. There are different ways of doing this depending on the type of host cell.

Heat Shock. Cells are incubated with the vector in a solution containing calcium ions at 0C. The temperature is then suddenly raised to about 40C. This heat shock causes some of the cells to take up the vector, though no one knows why. This works well for bacterial and animal cells.

Electroporation. Cells are subjected to a high-voltage pulse, which temporarily disrupts the membrane and allows the vector to enter the cell. This is the most efficient method of delivering genes to bacterial cells.

Viruses. The vector is first incorporated into a virus, which is then used to infect cells, carrying the foreign gene along with its own genetic material. Since viruses rely on getting their DNA into host cells for their survival they have evolved many successful methods, and so are an obvious choice for gene delivery. The virus must first be genetically engineered to make it safe, so that it cant reproduce itself or make toxins. Three viruses are commonly used:

1. Bacteriophages (or phages) are viruses that infect bacteria. They are a very effective way of delivering large genes into bacteria cells in culture.

2. Adenoviruses are human viruses that causes respiratory diseases including the common cold. Their genetic material is double-stranded DNA, and they are ideal for delivering genes to living patients in gene therapy. Their DNA is not incorporated into the hosts chromosomes, so it is not replicated, but their genes are expressed.

The adenovirus is genetically altered so that its coat proteins are not synthesised, so new virus particles cannot be assembled and the host cell is not killed.

3. Retroviruses are a group of human viruses that include HIV. They are enclosed in a lipid membrane and their genetic material is double-stranded RNA. On infection this RNA is copied to DNA and the DNA is incorporated into the hosts chromosome. This means that the foreign genes are replicated into every daughter cell.

After a certain time, the dormant DNA is switched on, and the genes are expressed in all the host cells.

Plant Tumours. This method has been used successfully to transform plant cells, which are perhaps the hardest to do. The gene is first inserted into the Ti plasmid of the soil bacterium Agrobacterium tumefaciens, and then plants are infected with the bacterium. The bacterium inserts the Ti plasmid into the plant cells' chromosomal DNA and causes a "crown gall" tumour. These tumour cells can be cultured in the laboratory and whole new plants grown from them by micropropagation. Every cell of these plants contains the foreign gene.

Gene Gun. This extraordinary technique fires microscopic gold particles coated with the foreign DNA at the cells using a compressed air gun. It is designed to overcome the problem of the strong cell wall in plant tissue, since the particles can penetrate the cell wall and the cell and nuclear membranes, and deliver the DNA to the nucleus, where it is sometimes expressed.

Micro-Injection. A cell is held on a pipette under a microscope and the foreign DNA is injected directly into the nucleus using an incredibly fine micro-pipette. This method is used where there are only a very few cells available, such as fertilised animal egg cells. In the rare successful cases the fertilised egg is implanted into the uterus of a surrogate mother and it will develop into a normal animal, with the DNA incorporated into the chromosomes of every cell.

Liposomes. Vectors can be encased in liposomes, which are small membrane vesicles (see module 1). The liposomes fuse with the cell membrane (and sometimes the nuclear membrane too), delivering the DNA into the cell. This works for many types of cell, but is particularly useful for delivering genes to cell in vivo (such as in gene therapy).

These are needed to identify cells that have successfully taken up a vector and so become transformed. With most of the techniques above less than 1% of the cells actually take up the vector, so a marker is needed to distinguish these cells from all the others. Well look at how to do this with bacterial host cells, as thats the most common technique.

A common marker, used in the R-plasmid, is a gene for resistance to an antibiotic such as tetracycline. Bacterial cells taking up this plasmid can make this gene product and so are resistant to this antibiotic. So if the cells are grown on a medium containing tetracycline all the normal untransformed cells, together with cells that have taken up DNA thats not in a plasmid (99%) will die. Only the 1% transformed cells will survive, and these can then be grown and cloned on another plate.

Replica plating is a simple technique for making an exact copy of an agar plate. A pad of sterile cloth the same size as the plate is pressed on the surface of an agar plate with bacteria growing on it. Some cells from each colony will stick to the cloth. If the cloth is then pressed onto a new agar plate, some cells will be deposited and colonies will grow in exactly the same positions on the new plate. This technique has a number of uses, but the most common use in genetic engineering is to help solve another problem in identifying transformed cells.

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Genetic Engineering - BiologyMad

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