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Genetic Modification
Michael Congdon
BME 181
What is genetic
engineering?
 The process of creating genetically modified
(transgenic) organisms through a laboratory process
in which genes from one species are extracted and
artificially implanted into the genes of another
 The genes may be sourced from any different
organism allowing for limitless options of genetic
combination
 This process breaks the natural barriers that
organisms contain to protect themselves against the
introduction of foreign DNA
Background
 1972-1973
 Genetic Engineering begins with Biochemist Herbert
Boyer and Stanley Cohen – Use enzymes to cut a
bacteria plasmid and insert another strand of DNA
 In doing this they successfully created recombinant
DNA (mixed DNA from two different organisms)
1994
 The first modern recombinant crop is approved for
sale in the United States
Recombinant DNA
 rDNA is a sequence of DNA that results from the
laboratory controlled creation of genetic material
from multiple sources
 Creates a sequence that otherwise would not exist
 Recombining DNA is possible because all DNA
molecules from all organisms share the same
chemical structure, but the variations occur in the
sequence of nucleotides within that structure.
 Introduced foreign DNA is replicated along with
the host DNA
Process
 There are a number of different ways that engineers
introduce foreign DNA into a species
 Using viruses or bacterium to “infect” animal or plant
cells with new DNA
 Coating DNA onto small metal pellets, and shooting
them into cells using a special gun
 Injecting the new DNA into fertilized eggs
 Using electric shock to create holes in the membrane
covering sperm, and forcing the new DNA into the
sperm through the holes
 A genetically modified organism itself consists of 3
main components
 gene of transfer (trans-gene)
 Target organism (host)
 And a vector to carry the gene into the target species
cells
 In order to isolate the trans-gene, usually restriction enzymes are
used to recognize specific sequences in the DNA and cut it at those
locations
 The DNA is cleaved at two points creating a smaller sequence of
interest
 Depending on how the enzyme slices the double-stranded sequence,
the resulting slice will contain sticky ends or blunt ends
 The trans gene is then inserted into a vector capable of penetrating
the cells of a target species. When done with a virus, the key is to
remove the parts of the genome that cause harm to a host cell, but
leave the part that allows the virus to penetrate the cell wall and
insert its biological information
 The host will now replicate, producing offspring that express the
inserted Trans-gene
Possibilities
Ethics
 Genetically modified organisms have generated a lot of attention
from environmentalists, scientists, and policy makers
 There's no doubt about the benefits that exist, but there is an
immense concern with possible consequences to the environment
and human health

Many of the effects that GMOs have on the organisms that live
around them is unknown
 For example If pollen from GMOs were to somehow fertilize a
compatible weed, the result might be a weed resistant to weed
killers
 Movements like occupy Monsanto exist to fight against the
influence and success of Monsanto, a company that is responsible
for a majority of the GMOs seen in American agriculture
Statistics
 From 1996 to 2006 the global hectares of GMOs grew from 1.7
million to 102 million. With a majority grown for herbicidal
tolerance
 Breakdown by country by amount of genetically modified
foods:
US – 68%
Argentina – 23%
Canada – 7%
China – 1%
Animal Specific
 One of the most common genetic modifications in
animals is hormone (BGH) increasing cow size and milk
production
 Cows treated with BGH have 79% increase in udder
infections
 This translates into the cows needing antibiotics as a source
of treatment
 Which in turn puts antibiotics directly into the milk they
produce
 In 1989 it was cited that 20% of milk on the market had
illegal antibiotics in it
 The year is 2013 and one can only imagine where that
number lies today
Resources

http://www.hudsonalpha.org/education/kits/gmod/gmo-ethics

http://en.wikipedia.org/wiki/Recombinant_DNA

http://www.guardian.co.uk/science/2011/sep/11/genetically-modified-glowing-cats

http://occupy-monsanto.com/

http://www.responsibletechnology.org/gmo-basics/the-ge-process

http://www.odec.ca/projects/2003/britt3m/public_html/makinggmo.htm

http://en.wikipedia.org/wiki/Genetically_modified_organism#Regulation

http://en.wikipedia.org/wiki/Timeline_of_genetically_modified_organisms

http://organic.lovetoknow.com/GMO_Statistics

http://fhs-bio-wiki.pbworks.com/w/page/22957102/Recombinant%20DNA%20(plasmids)