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Genetic Engineers can alter the DNA code of living organisms. Selective Breeding Recombinant DNA PCR Gel Electrophoresis Transgenic Organisms. Genetic Engineering. Changing the Living World Selective Breeding - PowerPoint PPT Presentation

Text of Genetic Engineering

  • Genetic EngineeringGenetic Engineers can alter the DNA code of living organisms.

    Selective Breeding

    Recombinant DNA

    PCR

    Gel Electrophoresis

    Transgenic Organisms

  • Changing the Living WorldSelective BreedingHumans use selective breeding, which takes advantage of naturally occurring genetic variation in plants, animals, and other organisms, to pass desired traits on to the next generation of organisms. All modern-day crops were cultivatedby this method as well as all breeds of dogs.Go to Section:

  • Selective breeding transformed teosinte's few fruitcases (left) into modern corn's rows of exposed kernels (right).

  • Teosinte ancestor of corn (Mexico)Cob selection5000BC 2cm3000BC 4cm1000AD 13cmBreeding and artificial selection

  • Variation in potatoes

  • Selective BreedingBreed only those plants or animals with desirable traits

    People have been using selective breeding for thousands of years with farm crops and domesticated animals.

  • The process by which desired traits of certain plants and animals are selected and passed on to their future generations is called selective breeding.Selective BreedingGenetics and BiotechnologyGerman shepherdService dogHuskySled dogSaint BernardRescue dog

  • Selective Breeding

    Inbreeding is the continued breeding of individuals with similar characteristics.

  • InbreedingThe controlled breeding of closely related organisms.Positive effects: controlled traits and characteristics. Pure bred dogsNegative effects: excessive inbreeding can produce unwanted effects because of lack of variation. Blindness in German shepherds

  • InbreedingHas risks due to the similarity of the genes between these two organisms. There is a higher risk of defective recessive alleles pairing up in their offspring. Ex. Blindness, deafness (white cats, dalmations) hip dysplasia -(GoldenRetrievers)

  • Hybridization The crossing of dissimilar individuals to bring together the best of both organisms.

  • So if inbreeding reduces variation and makes individuals very similar, how do you increase variation?

  • Increasing variationUse radiation or chemicalsCan produce new strains of bacteria and new plants.

  • Increasing VariationMutations can be induced to help create variation in organisms.Polyploidy plants have an extra chromosome.

  • PolyploidyHaving a multiple of the normal chromosome number.Example: regular chromosome number is 9. Polyploidy condition could be 18, 27, 36, etc.

  • More complex forms of genetic engineering includegene splicing, transferring genetic material from one organism to another

    Recombinant DNA

  • BiotechnologyA new field of biology that utilizes genetic engineering to produce new substances in the fields of health and industry.

  • Recombinant DNAThe manipulation and combination of DNA from two sources Bacterial DNA + human gene for insulinhttp://player.discoveryeducation.com/?guidAssetId=166DED13-FCC3-4388-82B7-07ED4987DDE5

  • Recombinant DNAThe ability to combine the DNA of one organism with the DNA of another organism.

    Recombinant DNA technology was first used in the 1970s with bacteria.

  • Recombinant BacteriaRemove bacterial DNA (plasmid).

    Cut the Bacterial DNA with restriction enzymes.

    Cut the DNA from another organism with restriction enzymes.

    Combine the cut pieces of DNA together with another enzyme and insert them into bacteria.

    Reproduce the recombinant bacteria.

    The foreign genes will be expressed in the bacteria.

  • Human CellGene for human growth hormoneSticky endsRecombinant DNAGene for human growth hormoneDNA insertionDNA recombinationBacterial cell for containing gene for human growth hormoneBacterial CellPlasmidBacterial chromosome

  • How recombination worksCut plasmid (circular piece of bacteria DNA that serves as a host) with restriction enzymeCut gene of interest with restriction enzymeSplice together gene of interest and plasmid

  • Cutting DNAUsually use a restriction enzyme : a chemical used to cut out a specific segment of DNA.

  • Cutting and PastingUse DNA synthesizers to make recombinant DNA (DNA from two different organisms spliced together)

  • Sneaking In

    You probably have heard of computer viruses. Once inside a computer, these programs follow their original instructions and override instructions already in the host computer. Scientists use small packages of DNA to sneak a new gene into a cell, much as a computer virus sneaks into a computer.

  • 1. Computer viruses enter a computer attached to some other file. What are some ways that a file can be added to a computers memory?A file can be downloaded from a CD or the Internet.

    2. Why would a person download a virus program?The computer user would not willingly download a virus but would download a program that appeared to be useful.

    3.If scientists want to get some DNA into a cell, such as a bacterial cell, to what sort of molecule might they attach the DNA?Possible answers: a useful protein or a strand of DNA that the cell would recognize and accept

  • VocabPlasmid - circular DNA molecule found in bacteriagenetic marker - gene that makes it possible to distinguish bacteria that carry a plasmid with foreign DNA from those that dontRecombinant DNA DNA that has been created artificially. DNA from two or more sources is incorporated into a single recombinant molecule.

  • PlasmidsA small circular molecule of DNAIt often has a DNA sequence that serves as an origin of replication.Contain genetic markers.

  • Vectors: is a DNA molecule used as a vehicle to transfer foreign genetic material into another cell Plasmids Virusesbacteriophages

  • Characteristics of a VectorCan replicate independently in the host cell Has restriction sitesHas a reporter gene marker that will announce its presence in the host cell (Anti-biotic resistance, P-Glo)Is a small size in comparison to the host chromosome for ease of isolation

  • Reporter gene: Genetic marker.

  • pGloTransformation of E. coli with the pGlo plasmid

    If the bacterium uptakes the plasmid it should glow in response to long range uv light

  • TransformationWhen a cell (usually a bacterium) takes in DNA from outside the cell and incorporates it into its own DNA.Example: Griffiths rats

  • Cell Transformation

    During transformation, a cell takes in DNA from outside the cell. This external DNA becomes a component of the cells DNA.

    Transforming BacteriaPlasmid circular DNA molecule found in bacteria.

    Why have plasmids been useful for DNA transfers?It has a DNA sequence (gene) that helps promote plasmid replication. If the foreign DNA manages to get inside, it will get replicated (copied).It has a genetic marker a gene that makes it possible to distinguish whether it is carrying the foreign DNA. They usually use a gene that is resistant to antibiotics. The bacterial cell will not die when exposed to an antibiotic. When exposed, if it doesnt die, you know the foreign DNA is inside.

    Section 13-3

  • Human CellGene for human growth hormoneRecombinant DNAGene for human growth hormoneSticky endsDNA recombinationDNA insertionBacterial CellPlasmidBacterial chromosomeBacterial cell for containing gene for human growth hormoneSection 13-3Figure 13-9 Making Recombinant DNA

  • Transforming Plants

  • Applications of Genetic Engineering1986 Steven Howell created the glow in the dark tobacco This proved the basic mechanism of how genes work was true for all living organisms.

    Transgenic OrganismsTransgenic - a organism which contains genes from another species.Genetic engineering has spurred the growth of biotechnology, which is a new industry that is changing the way we interact with the living world.

    Mice with jellyfish genes.Only glow underflorescent lights. Theypassed this gene to theiroffspring. 2002

  • Seen in ordinary light, one such pig appears yellowish. Under ultraviolet light, the pigs glow green.

  • Recognition sequencesDNA sequenceSection 13-2Restriction Enzymes

  • Recognition sequencesDNA sequenceRestriction enzyme EcoRI cuts the DNA into fragments.Sticky endSection 13-2Restriction Enzymes

  • Recombinant DNA in IndustryE. coli has been modified to produce an indigo dye to color blue jeansRecombinant DNA has been used to help production of cheese, laundry detergent, paper production, sewage treatmentIncrease enzyme activity, stability and specificity

  • Benefits of Recombinant BacteriaBacteria can make human insulin or human growth hormone.

    Bacteria can be engineered to eat oil spills.

  • Example of how Recombinant DNA helps humans:

    Pharmaceuticals:insulin for diabetics factor VIII for males suffering from hemophilia A factor IX for hemophilia B human growth hormone (GH) erythropoietin (EPO) for treating anemia three types of interferons several interleukins granulocyte-macrophage colony-stimulating factor (GM-CSF) for stimulating the bone marrow after a bone marrow transplant tissue plasminogen activator (TPA) for dissolving blood clots adenosine deaminase (ADA) for treating some forms of severe combined immunodeficiency (SCID) angiostatin and endostatin for trials as anti-cancer drugs parathyroid hormone leptin hepatitis B surface antigen (HBsAg) to vaccinate against the hepatitis B virus

  • Golden Rice- Agriculture biotechGolden rice is the result of an effort to develop rice varieties that produce provitamin-A (beta-carotene) as a means of alleviating vitamin A (retinol) deficiencies in the diets of poor and disadvantaged people in developing countries. Because traditional rice varieties do not produce provitamin-A, transgenic technologies were required.

  • Recombinant DNA in AgricultureCrops that stay fresh longer and are more resistant to diseasePlants resistant to herbicide so weeds can be killed easierHigher product yields or higher in vitaminsPeanuts and soybeans that dont cause allergic reactions

  • http://www.pbs.org/wgbh/nova/ancient/miracle-rice.html

    NOVA miracle of rice

  • http://www.teachersdomain.org/resource/tdc02.sci.life.gen.btcorn/

    Genetic engineered corn (5 minute video)

    http://www.teachersdomain.org/resource/tdc02.sci.life.gen.breeding/

    Classic breeding vs. genetic engineering video (3min)

  • Recombinant DNA in MedicineProduction of Human Growth Hormone to treat pituitary dwarfismInsulin Production by bacterial plasmidsAntibodies, hormones, vaccines, enzymes, and hopefully more in the future

  • VaccinesBananas have potential to become the world's first edible vaccine due to Agrobacterium. An edible vaccine doesn't need sterile syringes, costly refrigeration, or multiple injections. According to the World Health Organization (WHO), more than 2 million children die worldwide each year from diarrhea that can be prevented easily with vaccines.

  • The DNA of plants and animals can also be altered.

    PLANTS

    disease-resistant and insect-resistant crops

    2. Hardier fruit

    3. 70-75% of food in supermarket is genetically modified.

  • How to Create a Genetically Modified Plant1.Create recombinant bacteria with desired gene.

    2. Allow the bacteria to infect" the plant cells.

    3. Desired gene is inserted into plant chromosomes.

  • What do you think about eating genetically modified foods?

  • pGlo GfpGreen fluorescent protein

  • Green Fluorescent Protein and Plants

  • GFP and mice

  • Glo fishFluorescent zebra fish were specially bred to help detect environmental pollutants. By adding a natural fluorescence gene to the fish, scientists are able to quickly and easily determine when our waterways are contaminated

  • pGloTransformation of E. coli with the pGlo plasmidOriGene for GfpThe plasmid contains the genes for the Arabinose promoterThe plasmid contains the genes for ampicillin resistanceIf the bacterium uptakes the plasmid it should glow in response to long range uv light

  • Ha Ha Ha!

  • Genetic Engineering and Crime Scenes

  • What are we eating everyday?

  • FoodPropertiesPercent modified inUnited StatesSoybeansResistant to herbicides89%CottonPest-resistant cotton83%Hawaiian papayaResistant to ringspotvirus+50%

  • AquaAdvantage Salmon (created by AquaBounty), also known as Frankenfish,

  • http://www.youtube.com/watch?v=SDI1j2YR6Oohttp://www.teachersdomain.org/resource/tdc02.sci.life.gen.salmon/Aquabounty fish

    http://www.marklynas.org/2013/01/lecture-to-oxford-farming-conference-3-january-2013/Environmentalists apology for talking negative about GM foods 51:52 first 6 minutes

  • DNA ExtractionWhere is the DNA located in a cell?-the nucleusFirst must break apart the cell membrane and nucleus to get at the DNA

  • Manipulating DNAGenetic Engineering is the process of reading and changing DNA sequences in an organism.Reading the Genetic CodeDNA extractionCutting and Labeling DNASeparating DNAReading the DNA sequenceMaking Copies (PCR polymerase chain reaction)

  • Manipulating DNAGenetic Engineering is the process of reading and changing DNA sequences in an organism.Reading the Genetic CodeDNA extractionCutting and Labeling DNASeparating DNAReading the DNA sequenceMaking Copies (PCR polymerase chain reaction)

  • Manipulating DNAGenetic Engineering is the process of reading and changing DNA sequences in an organism.Reading the Genetic CodeDNA extractionCutting and Labeling DNASeparating DNAReading the DNA sequenceMaking Copies (PCR polymerase chain reaction)

  • Manipulating DNAGenetic Engineering is the process of reading and changing DNA sequences in an organism.Reading the Genetic CodeDNA extractionCutting and Labeling DNASeparating DNAReading the DNA sequenceMaking Copies (PCR polymerase chain reaction)

  • Gel Electrophoresisgslc

  • http://www.dnalc.org/resources/animations/gelelectrophoresis.html

  • DNA Fingerprinting

  • Gel ElectrophoresisPlacing a mixture of DNA into a gel and applying an electric current. DNA is then separated according to size.

  • Gel Electrophoresis

    This technology allows scientists to identify someones DNA!

  • Steps Involved in Gel Electrophoresis1. Cut DNA sample with restriction enzymes.

    2. Run the DNA fragments through a gel.

    3. Bands will form in the gel.

    4. Everyones DNA bands are unique and can be used to identify a person.

    5. DNA bands are like genetic fingerprints.

  • Perform your own Gel ElectrophoresisGo to this website to perform your gel electrophoresishttp://gslc.genetics.utah.edu/units/biotech/gel/Once you understand the process, use your DNA detective skills to help solve a mystery.http://www.pbs.org/wgbh/nova/sheppard/analyze.htmlOr google NOVA DNA FingerprintNOVA Online | Killer's Trail | Create a DNA Fingerprint

  • Uses of Gel ElectrophoresisDNA FingerprintingAn individual's DNA is as distinctive as a fingerprint. DNA samples can be obtained from the trace amounts of blood or sperm. These DNA samples can be separated using gel electrophoresis. The number and position of bands formed on each lane of gel is the actual genetic "fingerprint" of that DNA sample. The characteristics of certain segments of DNA vary from person to person and form a highly individual, detectable "genetic fingerprint." Developed only in the mid-1980s, genetic fingerprinting has rapidly become a widely used courtroom tool. In 1988 the first person in the United States was executed based on DNA technology.

    The Human Genome ProjectThe most ambitious research project made possible by DNA technology is the effort to map the entire human genome.

  • Genetic Engineering

  • Polymerase Chain ReactionPCRPCR allows scientists to make many copies of a piece of DNA.

    Heat the DNA so it unzips.

    2. Add the complementary nitrogenous bases.

    3. Allow DNA to cool so the complementary strands can zip together.

  • PCR Polymerase Chain ReactionMaking copies to work with.

  • Twins brothers, different parents after test tube mix-up Wilma and Willem Stuart were a Dutch couple who had been unsuccessfully trying to conceive for years and decided to try IVF. They soon learned they would be parents of twins. When the two boys were born, Koen had blue eyes, dark hair and pink skin, Tuen had dark eyes dark hair and brown skin. A DNA test revealed that Koen was the Stuarts child but Tuen was not Willems. The report of the investigation has not been made public, but speculation is that a piece of lab equipment called a pipette, like a large eyedropper, had been used twice, causing another mans sperm to be mixed with Willems. The hospital called it a deeply regrettable mistake. The Stuarts remembered there was a black couple in the waiting room the same day during the IVF process. The hospital located the man and confirmed he was Tuens biological father. Although he was under no obligation to meet his son he never knew he had, he did when Koen was 18 months old. The biological father only looked at him from a distance and didnt try to claim him and was comfortable that the Stuarts loved the child, and let them continue raising him.

  • Transgenic organismsWhen an organism contains genes from other organisms.Example:A tobacco plant that contained DNA from a firefly.

  • Genetically modified organisms are called transgenic organisms.

    TRANSGENIC ANIMALS

    Mice used to study human immune system

    Chickens more resistant to infections

    Cows increase milk supply and leaner meat 4. Goats, sheep and pigs produce human proteins in their milk

  • Transgenic AnimalsA transgenic sheep was produced that contained the corrected human gene for hemophiliaThis human gene inserted into the sheep produces the clotting protein in the sheeps milkThis protein can then be given to hemophilia patients

  • Human DNA in a Goat CellThis goat contains a human gene that codes for a blood clotting agent. The blood clotting agent can be harvested in the goats milk..Transgenic Goat

  • Desired DNA is added to an egg cell.How to Create a Transgenic Animal

  • Transgenic animalsLivestock can grow faster, better quality of meat, resistant to disease.Cows that produce human proteins in their milk.

  • Transgenic plantsUsually cash crops such as cotton, corn, wheat, soybeans, etc.Often incorporates bacterial DNA to make the crop resistant to disease, pests, or chemicals.Ex: Bt corn

  • Transgenic miceTwo baby mice - same ageHuman Growth hormone inserted into the embryo of the mouse on the left. Causes rapid growth in the newbornThe mouse on the right is a normal sized mouse

  • 1. Transgenic animals are often used in research. What might be the benefit to medical research of a mouse whose immune system is genetically altered to mimic some aspect of the human immune system? Students may say that a mouse with a humanlike immune system would be a good laboratory model for immune research.

    2. Transgenic plants and animals may have increased value as food sources. What might happen to native species if transgenic animals or plants were released into the wild?Transgenic organisms might disrupt normal balances in ecosystems and could breed with natural populations, changing them.

  • CloningClone: a member of a population of genetically identical cells produced from a single cell.1997: first mammal cloned. Dolly, the sheep.

  • How do you make a clone?

  • Cloning AnimalsDolly was the first animal cloned in 1997Since then, goats, mice, cattle, pigs, etc. have been clonedTake DNA out of embryonic stem cells or zygote and insert new DNA

  • Is cloning a good thing or a bad thing?Cloning articles

  • On December 27, 2002, the Raelians, an unusual religious sect, claimed that the first cloned human baby had been born. New reports were published by CNN, BBC, ABC, and most major media. Most scientists (including authors Ken Miller and Joe Levine) now believe that these reports were nothing more than an elaborate hoax.

  • Gene therapy

    http://player.discoveryeducation.com/?guidAssetId=7D2E6BA0-53A6-448B-A559-ED58D9E3E1AB

    http://player.discoveryeducation.com/?guidAssetId=B76C7495-F4F0-4CB4-926E-BFD46A3060A8

  • Gene pool: the sum total of all the heritable genes in a given population

  • Forces that Change Gene Frequencies

    1. Migration can change the gene frequency of a population if the migrants have a different gene frequency than that of the population they are leaving or entering.

  • Example

  • During a bottleneck, a large population undergoes a decrease in size so that relatively few individuals remain. Because there are few individuals, the gene frequency is more likely to drift.

  • http://www.pbs.org/wgbh/nova/body/cracking-your-genetic-code.html53:27

    Cracking Your Genetic CodeWe are on the brink of a new era of personalized, gene-based medicine. Are we ready for it? Airing March 28, 2012 at 9 pm on PBS Aired March 28, 2012 on PBS

    What will it mean when most of us can afford to have the information in our DNAall six billion chemical letters of itread, stored and available for analysis? "Cracking Your Genetic Code" reveals that we stand on the verge of such a revolution. Meet a cancer patient who appears to have cheated death and a cystic fibrosis sufferer breathing easily because scientists have been able to pinpoint and neutralize the genetic abnormalities underlying their conditions. But what are the moral dilemmas raised by this new technology? Will it help or hurt us to know the diseases that may lie in our future? What if such information falls into the hands of insurance companies, employers or prospective mates? One thing is for certain: the new era of personalized, gene-based medicine is relevant to everyone, and soon you will be choosing whether to join the ranks of the DNA generation.

  • http://www.npr.org/blogs/health/2012/12/03/165272373/genome-sequencing-for-babies-brings-knowledge-and-conflicts?sc=17&f=1001

    Genome sequencing for babies . NPR listen to the story 00:08:08

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