Post on 23-Feb-2016
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What is cloning?
• “assisted reproductive technology”• Ability to create genetically identical organisms by
transferring genetic information from one animal into an egg cell– Cloning does NOT change DNA
Why clone?
• Helps to maintain high quality livestock– Humans would eat the offspring of clones, not the
clone itself (ex. chickens from the Clone movie)• Quickly reproduces high quality livestock • Can be used to protect endangered species• Could help cure diseases and support organ
transplants (called Therapeutic Cloning)• Could allow infertile people to have children
How is an organism cloned?
• Artificial Embryo Twinning• Somatic Cell Nuclear Transfer
How is an organism cloned?
• Artificial Embryo Twinning1. Sperm cell fertilizes egg cell (cell is now called
embryo)2. Embryo naturally splits in two3. Scientist splits the two cells and puts them in
separate Petri dishes4. The cells divide and grow5. Cells go into surrogate mothers6. Identical twins are born
How is an organism cloned?
• Somatic Cell Nuclear Transfer1. Start with somatic cell (all chromosomes are
included)2. Empty nucleus from an egg cell3. Use electric shock to cause somatic cell and egg
cell to join (cell now called an embryo)4. Place embryo into surrogate mother5. Embryo grows and develops until clone is birthed
Successfully Cloned Animals
Risks of Cloning
• High failure rate – Success rate of 0.1 - 3%, • For every 1000 tries, 30 clones are made
• Clones are much bigger at birth and have abnormally large organs – Can lead to breathing problems, blood flow
problems, kidney or brain malformations, and impaired immune systems
Costs
• Cloning a cow costs between $10,000 and $20,000
Genetic Technology/Engineering• Genetic Technology provides
opportunities to change plants and animals genetically
• It can change the living world as we know it
• Includes:1.) Selective breeding2.) Biotechnology/genetic
engineering: Genetically Modified organisms
1.) Selective Breeding• Selective breeding is used to produce
organisms with desired traits• 2 ways to selectively breed:– Hybridization: Crossing two dissimilar
organisms to bring the best traits from both together• ex. Limequat and Tangelo
– Inbreeding: Crossing two very similar or closely related individuals in order to maintain a desired trait• ex. Dog breeding
Selective Breeding• Hybridization: ex. Limequat and Tangelo
• Inbreeding: ex. Dog breeding
2.) Biotechnology/genetic engineering
• Biotechnology/Genetic engineering involves manipulating DNA to transform organisms – makes it possible to cross genes that would not
normally happen in nature– involves cutting DNA from one organism and
inserting into the DNA of another (creates recombinant DNA)
– transgenic organisms – contain functional recombinant DNA from an organism of a different genus
Genetic Engineering: How do you insert DNA?
3 step process:1.) Isolate foreign DNA– Uses restrictive enzymes – bacterial proteins that can cut
DNA strands into specific nucleotide sequences2.) Attach DNA fragment to a carrier– uses vectors
• mechanical – micropipette, gene gun• biological – virus, plasmid (bacterial DNA)
3.) Transfer into host organism
Biotechnology/Genetic Engineering:
• Genetic Engineering results in:– Transformation: New DNA put into a new cell– Transgenic Organisms: Contains genes from other
species
Genetic Modification
• Combination of biotechology/genetic engineering and selective breeding
• Results in genetically modified organisms (GMOs)
• Almost everything has been genetically modified
• Usually used to make things bigger and better• Used a lot today with food
Possible Benefitsof GM Foods
Easing of world hunger Development of crops that
can be grown in marginal soil
Reduced strain on nonrenewable resources Development of drought
resistant crops Development of salt-
tolerant crops Development of crops that
make more efficient use of nitrogen and other nutrients
Possible Benefits of GM Foods
Reduced use of pesticides and herbicides►Development of pest
resistant crops ►Reduced herbicide
use is better for the environment and reduces costs for farmers
Possible Benefits of GM Foods
Improved crop quality Development of frost resistant
crops Development of disease
resistant crops Development of flood resistant
crops Improved nutritional quality
Development of foods designed to meet specific nutritional goals
Who makes sure GM foods are safe?
Government agencies regulate GM foods GM foods in the United
States are required to be labeled only if the nutritional value is changed or a new allergen is introduced.
Possible Risks of GM Foods
Insects might develop resistance to pesticide-producing GM crops
Herbicide-tolerant crops may cross-pollinate weeds, resulting in "superweeds"
Possible Risks for GM Foods
Certain gene products may be allergens, thus causing harm to human health
There may be unintended harm to wildlife and beneficial insects
Photo courtesy of T. W. Davies, Cal. Acad. of Sciences.
• fragments placed in “wells” formed in gel• electric field is applied forming +/- ends• DNA fragments separate based on size and
charge (smallest moves farthest away from wells)
Gel Electrophoresis:A method used to determine exactly what DNA fragments have been formed by restriction enzyme cutting
Other Genetic Technologies:
Human Genome Project
• Began in 1990. • The goal was to analyze the
entire human DNA sequence (6 billion base pairs)
• Originally scheduled to be completed in 2005
• In June 2003, the map was completed
• Cloning may be the next step