BioTech
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Genetic Puzzle
Our lives, as human beings, are dependent on Science. If we closely observe any aspect of how a machine operates, we’ll learn that every single action revolves around a specific scientific process or a complex form of scientific processes combined together. Our bodies are one of the clearest and most dominant examples in which such processes are demonstrated. Meanwhile, science is a strategic process upon which everything functions. As such, we can formulate the hypothesis which underlies the strong connection between science and technology. The more our understanding of their complexity increases, the more advanced technology becomes. Genetics is one of the most intriguing topics in which scientists have spent years and years perpetuating each other’s footsteps to come up with a specific conclusion about the reason why features differ in living organisms and how do that actually occur. Their very first theories of natural selection and evolution as well as discoveries of DNA strands, genes, alleles, chromosomes and genome have led the human entity to take a quite new path of exploration through which scientists were able to gather the puzzling pieces. Building blocks were already present but specifically during the last thirty years, scientists could reach the base upon which they built the innovation of genetically modified food.
In 1859, Charles Darwin published his book “The Origin of the Species” in which he explained variation, natural selection and evolution. Briefly, genetic variation, which is the difference between alleles in a specific trait, is caused by mutation. Mutation is the source of new variation resulting from sexual reproduction, genetic crossing over or any external factor like radiations (ultra-violet, X-ray and beta). This variation is the most crucial tool for the occurrence of natural selection which determines the existence organisms. Mainly, natural selection is the process in which organisms with traits well-suited to the environment survive and reproduce at a greater rate than organisms less suited to the environment. Over successive years, the choice of favorable characteristics changes the inherited genes amongst generations as they become more adapted. This process is called Evolution resulting from Natural Selection. Followed by Darwin, Gregor Mendel's publicized his discoveries on the breeding of peas, which became the foundation of modern genetics. Afterwards, all details about the nucleus were revealed one after the other throughout the years. The nucleus is a structure located inside any cell in the human body which contains 32 pairs of chromosomes. Mainly, chromosomes are made up of two chromatids attached together by a centromere. Each chromatid is made up of a DNA molecule. DNA is a double-stranded helix structure made up of nucleotides, each nucleotide carries a hydrogen base Adenine (A) or Guanine (G) or Cytosine(C) or Thymine(T). The two strands are linked together by hydrogen bonds between bases (A=T) (G≡C). Not only were such structures discovered but also processes like replication and cloning which were quite crucial for inventions like genetically modified food.
These discoveries as well as others have opened doors for researchers to come up with highly advanced ideas and techniques creating a stronger bond between science and technology. In 1974, Stanley Cohen, Annie Chang and Herbert Boyer created the first genetically modified DNA organism which is considered the initial steps of genetic engineering. Followed by, the production of a giant mouse by transferring growth hormone genes from a rat in 1982 and the creation of the first transgenic domestic animal, a pig in 1985. And then the big bomb came out of the dark in the shape of the first gene therapy trials on humans in 1991. Of course these implementations created a quite new path of thinking through which scientists created genetically modified food -mainly crops- to increase their nutrient content and value.
Genetically modified foods are foods derived from organisms whose genetic material (DNA) has been modified in a way that does not occur naturally (artificially) e.g. through the introduction of a gene from a different organism. Currently available GM foods stem mostly from plants, but in the future foods derived from GM microorganisms or GM animals are likely to be introduced on the market. Most existing genetically modified crops have been developed to improve yield, through the introduction of resistance to plant diseases or of increased tolerance of herbicides , this is because farmers wanted a method of killing weeds and harmful plants within their crops without the fear of harming their own crops. In the future, genetic modification could be aimed at altering the nutrient content of food, reducing its allergenic potential, or improving the efficiency of food production systems.
The very first Genetically Modified plant was produced in 1983 which was antibiotic-resistant tobacco plant. Another was "Flavr Savr"’s transgenic tomatoes, which were genetically modified for delayed ripening after picking. Many more crops were genetically modified to become antibiotic resistant and herbicide resistant such as, Bacillu Thuringiensis (Bt) corn/maize, (Bt) Potatoes, cotton resistant to the herbicide Bromoxynil, Soy Beans resistant to herbicide Glyphosate. In 2000 , with the Production of "Golden Rice" , scientists were able to Modify Crops increasing their nutrient content and value for the first time. As of 2011, the U.S. leads a list of multiple countries in the production of GM crops, and 25 GM crops had received regulatory approval to be grown commercially. As of 2013, roughly 85% of corn, 91% of soybeans, and 88% of cotton produced in the United States are genetically modified.
Genetic modification is alternating the Genome of the wanted organism by inserting a specific gene that codes for a wanted characteristic , Most of which are : High Yielding , disease resistance , vigorous growth under the prevailing conditions , growing the plant to the same height which makes their harvest easier . This can be Naturally done through inbreeding , which is selecting -for example- a plant that has vigorous growth and breeding it with another that has a high yield for many generations , this will give a plant with both of those characteristics. (Artificial Selection)
Another way is through Genetic Manipulation, as what has been done to Produce "Golden Rice" that has been genetically modified to contain Vitamin A which is only found in the Aleuronic layer of the grains and is removed during polishing of the grains. Vitamin A deficiency can cause increased risk of infection, night blindness and sometimes Total blindness, therefore scientists extracted genes responsible for the production of Vitamin A from daffodils and the bacterium Erwinia Uredovora , and inserted those genes into plasmids (DNA) of the bacteria called Agrobacterium Tumefaciens . These bacteria naturally infect plants, so they could introduce their genetically modified plasmids into rice cells allowing them to produce Vitamin A. When they are both mixed together – the GM bacterium and the rice embryos- in petri dishes, some embryos would get infected by the bacteria carrying the Vitamin A genes and this is how the process goes. Sounds like magic, doesn’t it?