gmo lecture
TRANSCRIPT
Genetically Modified Organisms
When you hear the word GMOs, what first comes to your mind?
A. Danger/Something badB. FarmersC. MonsantoD. Good/Something helpfulE. Nothing/ I don’t really know what a
GMO is….
What is a GMO? A genetically modified organism (GMO) is any organism whose genetic material has been altered using genetic engineering techniques. » Genetic engineering alters the genetic
make-up of an organism using techniques that remove heritable material or that introduce DNA prepared outside the organism either directly into the host or into a cell that is then fused or hybridized with the host. This involves using recombinant nucleic acid (DNA or RNA) techniques to form new combinations of heritable genetic material followed by the incorporation of that material into the host organism.
Video!!
DNA from
Species #1
DNA from Species #2
Recombinant DNA
• Recombinant nucleic acids (rDNA or rRNA) are the general name for result of taking a piece of one DNA and combining it with another strand of DNA. Recombinant DNA molecules are sometimes called chimeric DNA, because they are usually made of material from two different species.
• If genetic material from another species is added to the host, the resulting organism is called transgenic.
• If genetic material from the same species or a species that can naturally breed with the host is used the resulting organism is called cisgenic.
• Genetic engineering can also be used to remove genetic material from the target organism, creating a gene knockout organism.
Controversy starting with… definitions?• In the United States, genetic engineering
does not normally include traditional animal and plant breeding, in vitro fertilization, induction of polyploidy, mutagenesis, and cell fusion techniques that do not use recombinant nucleic acids or a genetically modified organism in the process. The above listed techniques would be considered means for genetic modification.
• However, the European Commission has defined genetic engineering broadly as including selective breeding and other means of artificial selection such as those techniques listed above. Thus, in Europe genetic modification is synonymous with genetic engineering.
GMOs are everywhere
GMOs are the source of genetically modified foods, and are also
widely used in scientific research and to produce goods other than food.
GMOs
Animals
PlantsMicrobes
GMO ResearchAgriculture• Improvement of crop yields• Herbicide resistance• Insect resistance• Drought, frost, and disease
resistance• Increased tolerance to salinity,
floods, and low nutrients • Increased nutrients produced
– Golden rice• Vaccines transport/intake
Medicine• Human insulin injections • Human growth hormone,
HGH• Blood clotting factor VIII• Hepatitis B vaccine • Diagnosing HIV infection
• Bt bacterium produce Cry toxins that have specific activities against insect species of the orders Lepidoptera (moths and butterflies), Diptera (flies and mosquitoes), Coleoptera (beetles), and Hymenoptera (wasps, bees, ants and sawflies).
• Thus, Bt serves as an important source of Cry toxins for production of biological insecticides and insect-resistant genetically modified crops.
Bacillus thuringiensis (Bt) - 1996
Roundup Ready Crops - 1996 • Roundup Ready crops are crops
genetically modified to be resistant to the herbicide Roundup. Roundup is the brand-name of a herbicide produced by Monsanto. Its active ingredient glyphosate was patented in the 1970s.
• These crops were developed to help farmers control weeds. Because the new crops are resistant to Roundup, the herbicide can be used in the fields to eliminate unwanted sensitive plants. Current Roundup Ready crops include soy, corn, canola, alfalfa, and cotton.
Stacked traits are more common
http://www.ers.usda.gov/data-products/adoption-of-genetically-engineered-crops-in-the-us/recent-trends-in-ge-adoption.aspx#.Uxjp_IWmXLk
Bt and HT Problems Toxins affect non-
target organisms Genetic drift to
invasive weedy species
“Super Species” – naturally resistance members of a population survive and reproduce, unable to be controlled
Solutions
Refuge in a bagMultiple Modes of ActionCrop Rotation
http://www.bt.ucsd.edu/assets/refuge.jpg
The first GM animal to be eaten by humans!
• AquAdvantage Salmon Market size in ½ the
time Grown as sterile, all
female populations Grown in land-based
facilities with containment
Chinook + Ocean Pout + Atlantic = GM Salmon
Gene 1
Gene 2
Is it safe?
How many of you would buy AquAdvantage Salmon?
A. YesB. NoC. I wouldn’t buy it either way cause I dislike
fish
http://www.monsanto.com/newsviews/pages/food-labeling.aspx
http://www.ecori.org/massachusetts-farming/2014/3/1/gmo-labeling-in-mass-faces-march-19-deadline.html
If you could buy a glow in the dark pet, would you?
A. HELL YES! That would be the coolest thing ever! B. No… way too freaky for me! C. I would, but I’m allergic D. Meh. I have better things to spend my money on.
These animals could cost anywhere between $6,000 and $28,000!
Can Genetically Modified Mosquitoes wipe out diseases like Malaria, Dengue Fever, and Chikungunya?
The Malaria Endemic • Malaria kills more than 1 million
people a year• 90% of malaria deaths occur among
young children in sub-Saharan Africa• Because malaria causes so much
illness and death, the disease is a great drain on many national economies. Since many countries with malaria are already among the poorer nations, the disease maintains a vicious cycle of disease and poverty.
Malaria Resistant Mosquitoes• Researchers led by Marcelo Jacobs-Lorena at the Malaria Research Institute
at Johns Hopkins University in Maryland created genetically modified mosquitoes by giving them a gene that made it impossible for them to pass on the plasmodium parasite that causes malaria. Around 1,200 GM mosquitoes were then released into a cage holding malaria-infected mice and the same number of wild mosquitoes.
• Over time, the researchers found that the GM mosquitoes slowly became the majority, reaching 70% in nine generations. The scientists believe that even though malaria-resistance weakened the mosquitoes by making them immune to the parasite, they fared better in the long term than insects infected with it because they lived longer and laid more eggs.
• "This fitness advantage has important implications for devising malaria control strategies," the team write in the journal Proceedings of the National Academy of Sciences.
Left: Mosquitoes become infected with the malaria parasite upon taking an infected human blood-meal. This produces an oocyst in the mosquito's gut wall (orange). When the oocyst ruptures, it releases sporozoites that pass through the gut (red) and into the hemocoel (white). The sporozoites are then amplified and migrate through the mosquito's body to the salivary glands, ready to infect a new human.
Right: The laboratory of Marcelo Jacobs-Lorena at Johns Hopkins University has identified receptor sites for proteins that are necessary for the malaria parasite to pass through the gut wall after the oocyst ruptures. The same receptors are involved with the passage of sporozoites into the salivary glands. The laboratory has produced small proteins that preferentially occupy these sites (blue), blocking transmission of sporozoites through the gut wall and into the salivary glands.
Dengue Fever and Chikungunya• High fever – up to
105°F• Severe headaches• Retro-orbital pain• Joint and muscle pain• Nausea, Vomiting,
Rashes• Bleeding from the
nose, gums, and under the skin
Above: Male mosquitoes created in the laboratories of Oxford University and Oxitec, a biotechnology company located in the south of England.
These male mosquitoes of the Aedes aegypti species will be on a mission to mate, but not to breed.
They are in fact designed to cause the wild females with whom they mate to produce offspring that die at the pupa stage with the aim of significantly reducing the native population below the numbers required to sustain dengue fever transmission.
Researchers at Oxitec Limited, created sterile male mosquitoes by manipulating the insects' DNA. Scientists in the Cayman Islands released 3 million mutant male mosquitoes to mate with wild female mosquitoes of the same species. That meant they wouldn't be able to produce any offspring, which would lower the population.
Mosquito numbers in that region dropped by 80 percent compared with a neighboring area where no sterile male mosquitoes were released.
What happens in the long run? Nobody knows."Nature often does just fine controlling its problems until we come along and blunder into it," Pete Riley, an anti-GM campaign director told the AP.
More Releases
US puts up a fight
Florida needs an effective Mosquito control plan
Florida must have research to continue the effectiveness and efficiency of Florida mosquito control to ensure Florida’s health and well-being. Contact Florida Mosquito Control Associationhttp://www.floridamosquito.org
• Critics worry that genetically engineering mosquitoes and releasing them into the wild—one proposed method for controlling the spread of malaria and other diseases —could cause those diseases to become more virulent.
What could possibly go wrong?• Once an organism is released into a new environment, it acts as an invasive or exotic species
which at times is detrimental to that environment. And it is recognized that invasive species form the third most important factor for environmental destruction the world over after habitat destruction and overkill of species. Twenty-four rabbits initially introduced to Australia have reproduced so successfully that they are seriously eating and destroying an already fragile ecosystem.
• GM mosquitoes are an invasive/exotic species because they have new traits not available in other mosquito species. Additionally, Aedes aegypti is an introduced species to Malaysia, and is already considered an invasive species. And how the genetic modification would affect these characteristics are currently unknown.
• Another form of unintended consequences could come from the genetic engineering process itself. When a new gene construct from one species is engineered to a target species, in this case the Aedes mosquito, the introduction can cause new behaviors apart from the intended ones, for example more aggressive mating or feeding behaviors.
• The larvae of the mosquitoes will die if there is no tetracycline, an antibiotic, in the water. But this antibiotic, which has been around since the 1950s, is widely used.
Eradication of the Screwworm Fly in southern United States
Why the big deal? • The Screwworm fly is an insect parasite of warm
blooded animals such as livestock, pets, and even humans.
• Prefers hot, humid climates – prevalent in the Southern US where large cattle ranches are found.
• Two species of Screwworm fly – “Old world”– “New world”
Eww…
• Adult flies breed in the wounds or open orifices of mammals.
• They lay up to 250 eggs in the injury. • Larvae enter the wound further and chew their
way into the underlying flesh. • They cause extensive tissue damage and are hard
to treat once inside the animal. • Infested animals can die from infection and loss of
tissue fluid.
Screwworm fly control
The United States Department of Agriculture (USDA) scientists demonstrated that both sexes of screwworm flies could be made sexually sterile by irradiating them as pupae.
Sterile insect technique is a method of biological control, whereby millions of sterile insects are released.
Screwworm flies mate once in a lifetime, and if one of the insect pair has been sterilized with gamma rays, neither will reproduce. The use of radioactivity for insect control was the first successful peaceful use of nuclear energy.
The last case of a screwworm fly infestation in the US was in 1966.