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Learning Target: Genetically Modified Organisms (GMOs) 1 Genetic Engineering I Can… Describe, in general terms, how the genetic information of an organism can be altered to give the organism new genetically based traits. I Will… • List examples of cloning of organisms occurring in nature. • Briefly describe the steps of Somatic Cell Nuclear Transfer (SCNT) in cloning mammals • Connect the structure of DNA and process of protein synthesis with reasons why genetic engineering is possible. • List the steps necessary to produce a transgenic organism 2 Genetic Engineering KEY CONCEPT: • DNA sequences of organisms can be changed. • Entire organisms can be cloned • New genes can be added to an organism’s DNA • Genetic engineering produces organisms with new traits Principles of genetics and cellular chemistry can be used to produce new foods and medicines in biotechnological processes. 3 Clone: • genetically identical copy of a gene or an organism Cloning occurs in nature: • Plants • Clone themselves from roots, stems and leaves • Plant tissue contains many stem cells that can develop into many types of cells 4 Cloning occurs in nature: Bacteria: • Clone themselves during asexual reproduction through binary fission 5 Cloning occurs in nature: Simple Animals: • Clone themselves during asexual reproduction through budding e.g. Hydra • Clone themselves during regeneration e.g. sea star 6 Cloning mammals – more difficult Somatic Cell Nuclear Transfer (SCNT) • Haploid nucleus removed from unfertilized egg gamete cell • Diploid nucleus from somatic cell inserted into the egg cell • Stimulated (chemicals and electricity) to go through mitosis and start dividing • Embryonic bastocyst (mass of cells) implanted in uterus • Develops into cloned offspring 23 46 7 First clone of an adult mammal: • Dolly the sheep (1977) • Many other mammals cloned since • Biotechnology companies clone beloved pets 8 Rainbow – Somatic cell DNA Allie – Surrogate mom CC – Cloned/Carbon Cat Egg donor– Anonymous Many Factors affect gene expression – Epistasis, Inactivation, Methylation, … 9 • Epigenetics Cloning: Controversial Pros • Creation of personal stem cells • Organ transplant • Treat diseases • Spinal cord injuries • Save endangered species Cons • Low success rate • Expensive • Health issues in clone • Reduces biodiversity • Ethic of “creating” life • When does life begin? 10 Genetic Engineering: • Changing and adding genes to an organism’s DNA to give it new traits • Clones genes not whole organisms How and why can we do this? DNA is UNIVERSAL! • DNA – 4 common nucleotides (A,T,G,& C) • DNA – Common double helix structure • RNA – Common 4 nucleotides (A, U, G, & C) • Codons – code for 20 common amino acids the make proteins 11 Genetic engineering is based on: • Recombinant DNA • DNA that contains genes from more than one organism • Engineer crops to be resistant to cold or insects • Engineer crops to produce vitamins or medicines • Engineer bacteria to produce medicines or enzymes 12 Bacterial plasmids are often used to make recombinant DNA Plasmid closed loop of DNA in bacteria separate from the bacterial chromosome • Will replicate on its own within the cell 13 Transgenic organism - has one or more genes from another organism inserted into its genome Transgenic bacteria used to make human insulin: • Gene inserted into plasmid • Plasmid inserted into bacteria • Bacteria expresses gene 14 Transgenic plants are common in agriculture: • Transgenic bacteria infect a plant • Plant expresses foreign gene • Many crops are now genetically modified (GM / GMO organism) 15 Scientists have concerns about some uses of genetic engineering: • Possible long-term health effects of eating GM foods • Allergies • Diseases • Possible effects of GM plants on ecosystem and biodiversity • Keystone species cascade effect • New vulnerabilities of engineered organism http://webertube.com/mediadetails.php?mid=8468& 16 Learning Check : List 4 reasons why genetic engineering is possible Genetically Modified Organisms (GMOs) 17 Learning Check : Name: ___________________ Learning Check : Name: ___________________ List 4 reasons why genetic engineering is possible List 4 reasons why genetic engineering is possible Learning Check : Learning Check : Name: ___________________ List 4 reasons why genetic engineering is possible Name: ___________________ List 4 reasons why genetic engineering is possible 18