Genetic Engineering. Inbreeding. Hybridization 10/23/2013. Selective Breeding vs. Genetic Engineering. Selective Breeding Recombinant DNA.

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1 Genetic Engineering Biology SPI , SPI 3210.T/E.2 Selective Breeding Recombinant DNA Transgenic Organisms Genetic Engineering Ethics Selective Breeding Choosing the best of the best (characteristics) and breeding the two organisms together to achieve the desired results perfection Inbreeding Hybridization Examples: breeding corn snakes, dogs, pigs, corn, flowers, potatoes, horses, etc. Inbreeding The most direct method of producing a desired offspring Purebred Problems/Risks: deformities in the joints progressive blindness in German shepherds and golden retrievers 3 4 Hybridization A cross between different (but related) species Usually hardier or more fit than the parents Aka hybrid vigor Corn disease resistance yield per acre nutritional value Selective Breeding vs. Genetic Engineering What kind of characteristics have food crops been selectively bred? What are some examples of harmful effects of selective breeding? When a breeder doesn t want to wait for the trait to appear naturally they can force a change through mutagenesis 5 6 1

2 Transgenics: Manipulating Genetics Mutagen Agent or substance that uses chemicals or radiation to force a change or mutation Some harmful Some beneficial (Discovery Education, 2002) 8 Mutagenesis The process of using mutagens to increase the mutation rate for a desired result Vehicle: Bacteria Small size and fast reproduction rate make bacteria the preferred method GMO s Genetically Modified Organism Any organism that has acquired one or more genes by artificial means Transgenic if the source of the new genetic material is from a different species Photo: Classical vs. Transgenic Breeding GE Techniques Plants domain.org/9 12/sci/life/gen/br eeding/index.html Animals Stem Cell Research 1. Genes are cut by restriction enzymes 2. DNA Recombination 3. DNA Insertion 4. DNA Sequencing

3 GE Techniques Cut and Paste DNA Restriction Enzyme: Source and Site of Action PCR Technique Polymerase Chain Reaction (PCR) produces billions of copies of a select segment of DNA

4 Step 1 1. Heat is added to separate strands 2. The mixture is cooled and primers bind to strands 3. DNA polymerase adds nucleotides to strands, producing two daughter molecules 4. The procedure is repeated, starting at Step 1. Step 2 Step 4 Just for fun: PCR song Step To compare the DNA from two different individuals a relatively large number of DNA copies are required. Polymerase chain reaction (PCR) enables scientists to rapidly generate billions of copies of a particular DNA sequence from a very small sample for chemical analysis. Gel This technique is widely used in basic genetic research diagnosing genetic disorders studying evolutionary relationships criminal investigations pharmaceuticals 21 DNA Fingerprinting Applications No human is exactly alike Tool used in criminal investigations Links to research:

5 DNA Fingerprint Forensic DNA Analysis 12/sci/life/gen/sheppard/index.html / bh/ / h alyze.html Ethical Impacts of Biotechnology Should genetic modifications to humans and other organisms be closely regulated? If future technology allows it, do you think parents should be able to choose specific characteristics for their babies? Do the benefits of new genetic tools outweigh the risks? List pros and cons. (Teacher s Domain, 2003) Medical Advances 1. Finding cures for illness 2. Development of new drugs 3. Stem cell research Finding Cures Ethics DNA Databases: 4:14 min Genetic Modification 4:27 min p g / /p g / /q / _qg_ qlg 15.html GM Fish Harvest of Fear 5:32 min

6 Designer Babies Cloning Diagram of plant cloning through tissue culture propagation GM Animals TransgenicManipulation activity (Freudenrich, 2001) 33 (Levine & Miller, 2012) GM Animals Scientists in Canada combined spider genes into the cells of lactating goats. The goats began to produce silk along with their milk. The silk can be extracted from the milk and woven into a thread that can be used to create a light, tough, and flexible material. (Levine & Miller, 2012) (Levine & Miller, 2012) 6

7 Genetically Modified Crops on the Market Corn Soybeans Cotton Canola Sugar beets Alfalfa Hawaiian Papaya Yellow crook neck and zucchini squash There are currently no genetically modified varieties of barley, edible beans, flax, oats, peas, rice, spelt, sunflowers, and wheat being grown. (Roseboro, 2011) Adoption of Genetically Engineered Crops in the U.S. This data product summarizes the adoption of herbicide tolerant and insect resistant crops since their introduction in The tablesbelow below for corn, cotton, and soybeans, provide the data obtained by USDA's National Agricultural Statistics Service (NASS) in the June Agricultural Survey annually for 2000 through Genetically engineered varieties of corn, upland cotton, and soybeans, by State and for the United States, Many people are interested in information about the global GE acreage. USDA does not collect these data. Estimates are produced by the International Service for the Acquisition of Agri biotech Applications (ISAAA) and can be found din the report, Global l Status t of Commercialized Transgenic Crops: See more on recent trends in GE adoption, and documentation to the data. (USDA, 2012) Are you eating GM foods? It s estimated that 60% of the US food products contain GE ingredients pie.cornell.edu//crops/ingredients.html (USDA, 2012) 42 7

8 Problems/Concerns Techniques of genetic modification allow scientists to change an organism's genetic code creating a plant or animal that never before existed Not surprisingly, this idea frightens many people They fear innumerable unforeseen possibilities, including creatures or diseases against which we have no defense. Many scientists strongly acknowledge these fears, saying that despite all we know about genetics, there is still much that remains shrouded in mystery. Resources Discovery Education. (2002). Transgenics: Manipulating Genetics. [Video Segment]. Available from Freudenrich, C. (2001). How Cloning Works. Retrieved January 23, 2011 from website Levine, J., Miller, K. (2012). Biology. New Jersey: Pearson Education, Inc. Mackean, D. (2009). IGCSE Biology, 2 nd ed. London, UK: Hodder Education. Nowicki, S. (2012). Holt McDougal Biology. Orlando: Houghton Mifflin Harcourt Publishing Company. Roseboro, K. (2011). The Non GMO Sourcebook. Retrieved June 27, 2012 from website United States Department of Agriculture. (2012). Adoption of Genetically Engineered Crops in the U.S. Retrieved June 27, 2012 from website products/adoptionof genetically engineered crops in the us/recent trends in ge adoption.aspx. 43 8