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Biotechnology

Biotechnology. Chapter 7. What is Biotechnology?. The use of technology to enhance living things Cloning Genetic Engineering Stem Cell Technology. Biotechnology. Cloning: Dolly and surrogate Mom. Embryonic stem cells and gene therapy. Genetic engineering: Genetically

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Biotechnology

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  1. Biotechnology Chapter 7

  2. What is Biotechnology? • The use of technology to enhance living things • Cloning • Genetic Engineering • Stem Cell Technology

  3. Biotechnology Cloning: Dolly and surrogate Mom Embryonic stem cells and gene therapy Genetic engineering: Genetically modified rice.

  4. Animal cloning Genetically modified foods and the American-European opinion divide. Gene cloning for pharmaceutical production DNA fingerprinting The promise and perils of embryonic stem cells Biotechnology We’ll examine:

  5. Clones • Clone – exact genetic duplicate of a cell or organism • 2 Types: • Natural Clone: • Asexual reproduction of simple organisms • Identical twins • Artificial Clone: man made clones

  6. Animal Cloning Dolly the first cloned mammal and her surrogate mother

  7. Why Clone? Five genetically identical cloned pigs To answer questions of basic biology For pharmaceutical production For herdimprovement To satisfy our desires (e.g. pet cloning) Environmental concerns

  8. Is Animal Cloning Ethical? The first cloned horse and her surrogate mother/genetic twin As with many important questions, the answer is beyond the scope of science!

  9. USU’s Contribution – A Cloned Mule and the First Cloned Equine

  10. The Biotechnology of Reproductive Cloning Even under the best of circumstances, the current technology of cloning is very inefficient. Cloning provides the most direct demonstration that all cells of an individual share a common genetic blueprint.

  11. Saved by Cloning? Endangered species can be cloned to help save the species Note the use of a closely related species, a domestic goat, as egg donor and surrogate mother

  12. (Science (2002) 295:1443) Carbon Copy– the First Cloned Pet Significantly, Carbon Copy is not a phenotypic carbon copy of the animal she was cloned from.

  13. The Next Step? Highly unlikely. Attempts at human cloning are viewed very unfavorably in the scientific community.

  14. Selective Breeding • = a method of breeding organisms to produce desired characteristics in the offspring • Used before technology made engineering possible • Luther Burbank (1849-1926) – considered the world’s foremost selective breeder • He produced over 800 different varieties of plants by selective breeding

  15. Selective Breeding • 2 types of selective breeding • In breeding – crossing similar individuals to get favorable characteristics in offspring May increase chance of mutation/genetic weakness • Hybridization – crossing dissimilar individuals to get desired traits.

  16. Selective Breeding • Hybrids – individuals produced by hybridization • Hybrid Vigor – when hybrids are hardier than either of the parents – often occurs in hybrids • Used a lot in modern agriculture

  17. Quiz time!

  18. Section 7.2 – Genetic Engineering • = Manipulation of genes using technology • Alters structure of DNA molecule by substituting genes from another DNA molecule • This technique permanently alters the DNA molecule and reduces the amount of time it takes to introduce genetic change

  19. Fourteen month-old genetically engineered (“biotech”) salmon (left) and standard salmon (right). Genetic Engineering

  20. Genetic Engineering These are mature and widely utilized biotechnologies DNA can be cut at specific sequences using restriction enzymes This creates DNA fragments useful for gene cloning

  21. Genetic Engineering • Process: • Restriction Enzymes used to cut a specific sequence out of a DNA molecule • The gene is inserted into the DNA of the recipient. This is called recombinant DNA because it is combined from two sources. • If the DNA is from two different species, it is called transgenic

  22. Genetic Engineering 4. The DNA is inserted back into a living cell. This can be done using a vector • Vector – agent used to carry a new gene from one organism to another • Expl – plasmid – small circular piece of bacterial DNA

  23. The enzyme EcoRI cutting DNA at its recognition sequence Restriction Enzymes are Enzymes That Cut DNA Only at Particular Sequences Restriction enzyme animation Different restriction enzymes have different recognition sequences (they cut at different places) This makes it possible to create a wide variety of different gene fragments

  24. DNA Pieces Cut by a Restriction Enzyme Can be Joined Together in New Ways These are recombinant DNA and they often are made of DNA from different organisms

  25. Plasmids are Used to Replicate a Recombinant DNA Plasmids are small circles of DNA found in bacteria. Plasmids replicate independently of the bacterial chromosome. Pieces of foreign DNA can be added within a plasmid to create a recombinant plasmid. Replication often produces 50-100 copies of a recombinant plasmid in each cell.

  26. Harnessing the Power of Recombinant DNA Technology – Human Insulin Production by Bacteria

  27. Human Insulin Production by Bacteria and cut with a restriction enzyme 6) join the plasmid and human fragment

  28. Human Insulin Production by Bacteria Mix the recombinant plasmid with bacteria. Screening bacterial cells to learn which contain the human insulin gene is the hard part.

  29. Route to the Production by Bacteria of Human Insulin One cell with the recombinant plasmid A fermentor used to grow recombinant bacteria. This is the step when gene cloning takes place. The single recombinant plasmid replicates within a cell. Then the single cell with many recombinant plasmids produces trillions of like cells with recombinant plasmid – and the human insulin gene.

  30. Route to the Production by Bacteria of Human Insulin The final steps are to collect the bacteria, break open the cells, and purify the insulin protein expressed from the recombinant human insulin gene.

  31. Route to the Production by Bacteria of Human Insulin Overview of gene cloning. Cloning animation

  32. Pharming These goats contain the human gene for a clot-dissolving protein that is produced in their milk. Pharming is the production of pharmaceuticals in animals engineered to contain a foreign, drug-producing gene.

  33. Section 7.3 – Stem Cell Technology

  34. The Stem Cell Concept A stem cell is an undifferentiated, dividing cell that gives rise to a daughter cell like itself and a daughter cell that becomes a specialized cell type.

  35. Stem Cells are Found in the Adult, but the Most Versatile Types of Stem Cells are Embryonic Stem Cells

  36. The Inner Cell Mass is the Source of Embryonic Stem Cells The embryo is destroyed by separating it into individual cells for the collection of ICM cells.

  37. Some Ethical Questions Are these masses of cells a human? Christians believe yes according to Ps 139:13-16 Is it ethical to use embryonic stem cells from embryos? Christians believe no!

  38. Cultured mouse embryonic stem cells. Additional Potential Dilemmas – Therapeutic Cloning to Obtain Matched Stem Cells Cells from any source other than you or an identical twin present the problem of rejection. So how can matched stem cells be obtained? Cloned somatic cells of a person can be made, and stem cells harvested from these clones.

  39. Therapeutic Cloning Is there any ethical difference between therapeutic and reproductive cloning? Yes! No one dies!

  40. Section 7B – Practical Uses of Biotechnology 1. Gene Therapy – technique to correct a defective gene • Very similar to the production of insulin by bacteria or clot dissolving protein by goats

  41. 2. DNA Fingerprinting A DNA fingerprint used in a murder case. The defendant stated that the blood on his clothing was his. Whose blood was on the defendant’s shirt?

  42. DNA Fingerprinting Basics Different individuals carry different alleles. Alleles useful for DNA fingerprinting differ in the number of repetitive DNA sequences they contain.

  43. DNA Fingerprinting Basics DNA is cut with a restriction enzyme and DNA fragments of different sizes are produced. A DNA fingerprint is made by analyzing the sizes of DNA fragments produced from a number of different sites in the genome that vary in length. A known sample is compared to an unknown. The more similarities, the more likely they came from the same or similar sources victim

  44. A Site With Three Alleles Useful for DNA Fingerprinting DNA fragments of different size will be produced by a restriction enzyme that cuts at the points shown by the arrows.

  45. The DNA Fragments Are Separated on the Basis of Size using Electric Current The technique is gel electrophoresis. Shorter fragments travel farther in the gel.

  46. A DNA Fingerprint When many genes are analyzed the chance that two patterns match by coincidence is infinitesimally small. What do we use DNA fingerprinting for? Paternity/family relationships Identification of the dead Solving crime

  47. Section 7.6 - Genetically Modified Organisms • GMO’s • Plants are often modified for: • Disease resistance • Increased flavor or nutrient content • Herbicide or pest resistance • Longevity

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