Biotechnology and GeneticBiotechnology and Genetic Engineering

Human Cloning-The SciencegIn The News

BiotechnologyBiotechnology

• Use of scientific & engineering principalsUse of scientific & engineering principals to manipulate organisms or their genes

Products of BiotechnologyProducts of Biotechnology

• Organisms with special biochemical• Organisms with special biochemical, morphological, and/or growth characteristics

• Organisms that produce useful products

• Information about an organism or tissue that would other wise not be known

Classical BiotechnologyClassical Biotechnology

• Propagation to get selected characteristicsPropagation to get selected characteristics

Plants derived from wild mustard

Techniques for Classical Bi h lBiotechnology

• Selection

• Hybridizationy

• Mutation• Mutation

HybridHybrid • Offspring from crossing two genetically p g g g y

similar varieties of a species

• Cross between two different species

Hybrid VigorHybrid Vigor

• Hybrid improved in certain ways overHybrid improved in certain ways over parents

Stronger– Stronger– With higher yields

Important Microbiology EventsImportant Microbiology Events

• PasturizationPasturization – Louis Pasteur (1860s)– Process to kill microorganisms that causeProcess to kill microorganisms that cause

fermentive change

• Germ theory– Robert Koch (late 1800s)– Germs cause infection– Developed pure culture methods

AntibioticsAntibiotics• Alexander FlemingAlexander Fleming

(1927)

– Mold that contaminated cultures killed bacteria

– Began process of screening for antibioticsscreening for antibiotics

Molecular BiotechnologyMolecular Biotechnology

• Manipulating genesManipulating genes• Genetic recombination

E h f DNA b t– Exchange of DNA sequences between molecules

Bacterial Exchange of DNABacterial Exchange of DNA• Transformation• Transduction • ConjugationConjugation

TransformationTransformation• Donor bacteriumDonor bacterium

– Lysed– Releases DNAReleases DNA

• Recipient bacterium• Recipient bacterium– Take up DNA

• Can be induced

TransductionTransduction• Virus transfers DNA from donor to recipient

ConjugationConjugation

• Donor & recipient make contact

• DNA is transferred

• Transfer in bacteria with plasmids

PlasmidsPlasmids

• Extra chromosomal pieces of DNAExtra chromosomal pieces of DNA

R li t i d d tl• Replicate independently

• Small portion of bacteria’s DNA

• Contain genes that promote transfer

Engineering Gene TransferEngineering Gene Transfer• Recombinant DNA technologygy• Individual genes isolated and transferred

Applications of BiotechnologyApplications of Biotechnology

P d i t i f th ti• Producing proteins for therapeutic use• Producing vaccines• DNA fingerprinting• Research on genome structure & functionResearch on genome structure & function• Gene therapy to treat disease

M difi ti f f d• Modification of food

Producing Therapeutic ProteinsProducing Therapeutic Proteins

• Insert genes into bacteriaInsert genes into bacteria• Manipulate bacteria to produce proteins

P if t i f• Purify proteins for use

Finding the Gene of InterestFinding the Gene of Interest• Shotgun cloning

– Isolating & purifying genomic DNA

C tti DNA i t f t– Cutting DNA into fragments

I t f t i t b t i t– Insert fragments into bacteria or yeast

Results in complete genomic library– Results in complete genomic library

Library screened to find desired gene– Library screened to find desired gene

DNA into Gene FragmentsDNA into Gene Fragments• DNA clipped with restriction enzymespp y

– Recognize certain DNA sequences

Cloning GenesCloning Genes

• Restriction fragments into bacteria orRestriction fragments into bacteria or yeast using plasmids or viruses

Complementary DNA (cDNA) Cl iCloning

• Gene of interest is known

• Messenger RNA from gene available

• Use reverse transcriptase to make gene

• Can be expressed in bacterial systems

Gene Synthesis CloningGene Synthesis Cloning

• Desired sequence must be known

• Laboratory made gene inserted into yeast or bacteriayeast or bacteria

U d f i li l i l• Used for insulin cloning as example

Screening for Desired GenesScreening for Desired Genes

DNA ProbesDNA Probes

• Molecule that binds to a specific geneMolecule that binds to a specific gene

T f DNA P b• Types of DNA Probe

– Molecules of RNA

– Complementary sequences of DNA

Genetically Engineered VaccinesGenetically Engineered Vaccines

• Vaccines stimulate anVaccines stimulate an immune response

• Benefit of genetically engineered vaccineg– Non pathogenic

DNA VaccinesDNA Vaccines

• DNA sequence of pathogen injected• DNA sequence of pathogen injected • Immune system develops antibodies• Advantages

– No risk of infection– No risk of illness from contamination– Long lasting immune response– Can administer many vaccines in a single shot

DNA FingerprintingDNA Fingerprinting

• DNA fragments amplified

• Fragments drawn through gel

• Bands visualized by dyes

• Humans have unique patterns

Polymerase Chain Reaction(PCR)(PCR)

• Makes copies of DNA fragments

• Allows for analysis starting with small samplessmall samples

• Gives large number of copies

PCR can be AutomatedPCR can be Automated

ElectrophoresisElectrophoresis• Separates DNA fragmentsp g

DNA Fingerprints & PaternityDNA Fingerprints & Paternity

Human Genome ProjectHuman Genome Project

• Sequence of Human DNA

• 3 billion base pairs

• 30,000 to 40,000 genes

GenomicsGenomics

• Subdiscipline of geneticsSubdiscipline of genetics

M i i & l i• Mapping, sequencing, & analyzing

• Two areas– Structural genomicsStructural genomics– Functional genomics

DNA Arrays (DNA Chips)DNA Arrays (DNA Chips)• Allows screening of thousands of genes

Gene TherapyGene Therapy

• Uses recombinant DNA to treatUses recombinant DNA to treat genetic disorders

• Replaces defective genes

• Includes targeted gene repairg g p

Food Modification with Bi h lBiotechnology

• Increase yieldIncrease yield

• Increase quality• Increase quality

M difi ti f i i• Modification of genes in organisms

• Example: transgenic plants– Genetically altered

Transgenic & Cloned AnimalsTransgenic & Cloned Animals• Dolly

– First cloned animal– Nuclear transfer from cell to produce embryo

Transgenic & Cloned AnimalsTransgenic & Cloned Animals

• Bioengineered animalsBioengineered animals– Combine desired traits

Cow example:– Cow example:• Heavy muscle• Low fatLow fat

Genetic Engineering CControversy

• Potential dangers existPotential dangers exist

E i t d b N ti l• Experiments governed by National Institute of Health

• Genetically modified foodsy– Common in U.S.– Opposed by EuropeOpposed by Europe

Arguments Against Bi i iBioengineering

• Long term safety of engineered foodsLong term safety of engineered foods• Spread of bioengineered genes