Genetically Modified Organisms Biology Essay

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A genetically modified organism or a genetically engineered organism is an organism whose genetic material has been altered using genetic engineering techniques. These techniques generally known as recombinant DNA technology , use DNA molecules from different sources , which are combined into one molecule to create a new set of genes. This DNA is then transferred to the organism giving it the new or modified gene. Transgenic organisms a subset of GMO's are organisms which have inserted DNA that originated in a different species.

The general principal for producing a GMO is to insert or delete into an organisms genome. This process is called genetic engineering and this was made possible only after the discovery of the DNA and the creation of the first recombinant bacteria in 1973 an existing bacterium E.coli expressing an exogenic Salmonella gene. This led to concerns in the scientific community about potential risks from genetic engineering, which were first discussed in depth at the Asilomar Conference  in 1975. One of the main recommendations from this meeting was that government oversight of recombinant DNA research should be established until the technology was deemed safe.

Herbert Boyer then founded the first company to use recombinant DNA technology, Genentec and in 1978 the company announced creation of an E.coli  strain producing the human protein insulin.

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

Small scale experimental plantings of genetically modified (GM) plants began in Canada and the U.S. in the late 1980s. The first approvals for large scale, commercial cultivation came in the mid 1990s. Since that time, adoption of GMO plants by farmers has increased annually.

In 1987, the first field tests of genetically engineered crops (tobacco and tomato) were conducted in the United States.

In the late 1980s and early 1990s guidance on assessing the safety of genetically engineered plants and food emerged from organizations including the FAO and the WHO.

In 2000, International Bio safety Protocol was approved by 130 countries at the Convention on Biological Diversity in Montréal, Canada. The protocol agrees upon labelling of genetically engineered crops, but still needs to be ratified by 50 nations before it goes into effect.


GMO's are used in biological and medical research, production of pharmaceutical drugs, experimental medicines i.e. gene therapy and agriculture. The term genetically modified organisms does not always imply but can include targeted insertions of genes from one species to the other. For example, a gene

from a jellyfish, encoding a fluorescent  protein called GFP, can be physically linked and thus co expressed with mammalian genes to identify the location of the protein encoded by the GFP-tagged gene in the mammalian cell. Such methods are useful tools for biologists in many areas of research, including those who study the mechanisms of human and other diseases or fundamental biological processes in eukaryotic or prokaryotic cells.

Till now the most controversial and also the most widely accepted application of the GMO's is patent protected food crops that are resistant against the pesticides and the herbicides. The largest share of such crops is being owned by the U.S. firm Monsanto. Their plants increased by 13% in 2007 from 2006.However the patent on the first Monsanto plant would expire in 2014. In addition to this a report from the European Joint Research Commission has been predicted that by 2015 40 % more such crops would be available in the market by Asia.

Transgenic animals are also becoming useful commercially. In 2009, February 6, the U.S. Food and Drug Administration approved the first human biological drug produced by the goat. The drug was named ATyrn . It is an anticoagulant which reduces the probability of blood clots during surgery or child birth. It is extracted from the goats milk.


Transgenic microbes have many commercial and practical applications, including the production of mammalian products. A company called Genentech was among the earliest and most successful commercial enterprises to use genetically engineered bacteria to produce human proteins. Their first product was human insulin produced by genetically engineered E. coli. A variety of other human blood proteins and immune modulators are now produced in a similar fashion, in addition to vaccines for such infectious agents as hepatitis B virus and measles.

Another promising application of genetically engineered microbes is in environmental cleanup, or bio mediation. Scientists have discovered many naturally occurring genes that code for enzymes that degrade toxic wastes and

wastewater pollutants in bacteria. Examples include genes for degrading chlorinated pesticides, chlorobenzenes, naphthalene, toluene, anilines, and various hydrocarbons. Researchers are using molecular cloning to introduce these genes from several different microbes into a single microbe, creating "super microbes" with the ability to degrade multiple contaminants.


The benefits of these animals to human welfare can be grouped into areas:




The examples below are not intended to be complete but only to provide a sampling of the benefits.

1. Agricultural Applications

a) breeding 

Farmers have always used selective breeding to produce animals that exhibit desired traits (e.g., increased milk production, high growth rate).Traditional breeding is a time-consuming, difficult task. When technology using molecular biology was developed, it became possible to develop traits in animals in a shorter time and with more precision. In addition, it offers the farmer an easy way to increase yields.

b) quality 

Transgenic cows exist that produce more milk or milk with less lactose or cholesterol12, pigs and cattle that have more meat on them, and sheep that grow more wool18. In the past, farmers used growth hormones to spur the development of animals but this technique was problematic, especially since residue of the hormones remained in the animal product.

c) disease resistance 

Scientists are attempting to produce disease-resistant animals, such as influenza-resistant pigs, but a very limited number of genes are currently known to be responsible for resistance to diseases in farm animals.

2. Medical Applications

a) xenotransplantation 

Patients die every year for lack of a replacement heart, liver, or kidney. For example, about 5,000 organs are needed each year in the United Kingdom alone. Transgenic pigs may provide the transplant organs needed to alleviate the shortfall. Currently, xenotransplantation is hampered by a pig protein that can cause donor rejection but research is underway to remove the pig protein and replace it with a human protein.

b) nutritional supplements and pharmaceuticals 

Products such as insulin, growth hormone, and blood anti-clotting factors may soon be or have already been obtained from the milk of transgenic cows, sheep, or goats. Research is also underway to manufacture milk through transgenesis for treatment of debilitating diseases such as phenylketonuria (PKU), hereditary emphysema, and cystic fibrosis.

In 1997, the first transgenic cow, Rosie, produced human protein-enriched milk at 2.4 grams per litre. This transgenic milk is a more nutritionally balanced product than natural bovine milk and could be given to babies or the elderly with special nutritional or digestive needs. Rosie's milk contains the human gene alpha-lactalbumin.

c) human gene therapy 

Human gene therapy involves adding a normal copy of a gene (transgene) to the genome of a person carrying defective copies of the gene. The potential for treatments for the 5,000 named genetic diseases is huge and transgenic animals could play a role. For example, the A. I. Virtanen Institute in Finland produced a calf with a gene that makes the substance that promotes the growth of red cells in humans.

3. Industrial Applications

In 2001, two scientists at Nexia Biotechnologies in Canada spliced spider genes into the cells of lactating goats. The goats began to manufacture silk along with their milk and secrete tiny silk strands from their body by the bucketful. By extracting polymer strands from the milk and weaving them into thread, the scientists can create a light, tough, flexible material that could be used in such applications as military uniforms, medical micro sutures, and tennis racket strings.

Toxicity-sensitive transgenic animals have been produced for chemical safety testing. Microorganisms have been engineered to produce a wide variety of proteins, which in turn can produce enzymes that can speed up industrial chemical reactions.


In biological research, transgenic fruit flies (Drosophila melanogester) are model organisms used to study the effects of genetic changes on development Fruit flies are often preferred over other animals due to their short life cycle, low maintenance requirements, and relatively simple genome compared to many vertebrates.


These are an important category of genetically modified organisms.