“Genetic Engineering is a process in which recombinant DNA (rDNA) technology is used to introduce desirable traits into organisms.”  Breeding to bring out traits in animals has been around for a long time and has produced successful results, but genetic engineering is a much more targeted and powerful method. In 2009, the FDA released a final guidance for industry on regulation of genetically engineered animals. 
Aside from the fact that genetic engineering allows you to produce specific traits as opposed to breeding and hoping that a certain trait comes out, breeding a certain species is restricted to the traits already found in the species or a close relative. Genetic engineering has no such restriction. “A breeder who wants a purple cow would be able to breed toward one only if the necessary purple genes were available somewhere in a cow or a near relative to cows…. If purple genes are available anywhere in nature—in a sea urchin or an iris—those genes could be used in attempts to produce purple cows.”  In this way, genetic engineering had breeding beat in specificity of the desired traits, time required to produce the traits, and available traits to apply to a species.
Despite the fact that genetic engineering is not limited to traits that already exist in a specific species, this does not mean that the genes are automatically compatible. There are still risks to genetic engineering. The funny thing about genes is that sometimes, two seemingly unrelated traits can be controlled by the same gene. It’s possible that when using one organism to engineer another, more than just the trait you desire will be shared. For example, a Brazilian nut gene was added to soy beans, and while the soy beans acquired the desired nut trait, they also acquired the allergenic tendency of the nut, producing allergic reactions in the test subjects who were allergic to nuts. 
As far as human genetic engineering goes, as we see with Khan in Into Darkness, there is not a lot of data. Currently, the ethics of genetic testing and engineering in humans is still being debated in the scientific community and in the public. People tend to get more scared when they think of applying a technique being used on plants and animals to humans, and many people have reservations on human genetic engineering. Frankly, many people have reservations when it comes to engineering plants or animals that they eat, too. This is typically from a lack of information or knowledge, but it certainly means that people are not happy about the prospect of genetically engineering us. On either side of the debate are the people who don’t want to risk giving people incompatible genes or surprise traits that happen to come with the gene carrying the desired trait, and people who feel that parents have the right to give their child a good life despite not being able to pass down certain traits. One thing that both sides agree on, though, is that no one wants eugenics (except Khan). 
. “U.S. Food and Drug Administration.” Genetic Engineering. N.p., 10 June 2014. Web. 03 Oct. 2014. <http://www.fda.gov/AnimalVeterinary/DevelopmentApprovalProcess/GeneticEngineering/default.htm>.
. “U.S. Food and Drug Administration.” Genetically Engineered Animals. N.p., 11 Sept. 2014. Web. 03 Oct. 2014. <http://www.fda.gov/AnimalVeterinary/DevelopmentApprovalProcess/GeneticEngineering/GeneticallyEngineeredAnimals/default.htm>.
. “What Is Genetic Engineering?” Union of Concerned Scientists. N.p., n.d. Web. 03 Oct. 2014. <http://www.ucsusa.org/food_and_agriculture/our-failing-food-system/genetic-engineering/what-is-genetic-engineering.html#.VC7IEq3ALFY>.
. “Genetic Engineering Risks and Impacts.” Union of Concerned Scientists. N.p., n.d. Web. 03 Oct. 2014. <http://www.ucsusa.org/food_and_agriculture/our-failing-food-system/genetic-engineering/risks-of-genetic-engineering.html#.VC7Nzq3ALFY>.
. Parry, Wynne. “Designing Life: Should Babies Be Genetically Engineered?” LiveScience. TechMedia Network, 18 Feb. 2013. Web. 03 Oct. 2014. <http://www.livescience.com/27206-genetic-engineering-babies-debate.html>.
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