Recombinant DNA and Genetic Engineering

Recombinant DNA and Genetic Engineering

Chapter 12Chapter 12

Goals for this chapterGoals for this chapter

Have a general understanding of Genetic Engineering and Biotechnology

Be able to form an opinion that is based on fact or emotion

And recognize the difference

Have a general understanding of Genetic Engineering and Biotechnology

Be able to form an opinion that is based on fact or emotion

And recognize the difference

Focus our attention onFocus our attention on

Genetic Improvement of Crop Plants

Other possible topics Genetic improvement of animals Genetic improvement of Humans Stem cell therapy Forensics Historical research And on and on

Genetic Improvement of Crop Plants

Other possible topics Genetic improvement of animals Genetic improvement of Humans Stem cell therapy Forensics Historical research And on and on

What is BiotechnologyWhat is Biotechnology

Definitions

Biotechnology Genetic Engineering Recombinant DNA Transgenic or GMO

Definitions

Biotechnology Genetic Engineering Recombinant DNA Transgenic or GMO

BiotechnologyBiotechnology

Genetic Improvement of plants and animals This would include the activities of Plant

Breeders

And plant breeders are really nice people

Genetic Improvement of plants and animals This would include the activities of Plant

Breeders

And plant breeders are really nice people

Genetic ChangesGenetic Changes

Humans have been changing the genetics

of other species for thousands of years

Artificial selection of plants and animals

Natural processes also at work

Mutation, crossing over

Humans have been changing the genetics

of other species for thousands of years

Artificial selection of plants and animals

Natural processes also at work

Mutation, crossing over

Traditional plant breedingTraditional plant breeding

Select parents Cross and generate variable offspring Select the desired types Test - Test - Test Multiply Release 7 to 15 years

Select parents Cross and generate variable offspring Select the desired types Test - Test - Test Multiply Release 7 to 15 years

Norman BorlaugNorman Borlaug

Nobel Peace Prize 1970 The Green Revolution

http://nobelprize.org/peace/laureates/1970/borlaug-lecture.html

Nobel Peace Prize 1970 The Green Revolution

http://nobelprize.org/peace/laureates/1970/borlaug-lecture.html

Barbara MclintockBarbara Mclintock

Transposons 1983 Nobel Prize

in Medicine

Transposons 1983 Nobel Prize

in Medicine

Genetic EngineeringGenetic Engineering

Modern Biotechnology - which uses the knowledge of DNA to manipulate the genetic makeup of an organism

Recombinant DNA - take a gene from one organism and place it into another organism

Transgenic or GMO - an organism that contains DNA from another organism

Modern Biotechnology - which uses the knowledge of DNA to manipulate the genetic makeup of an organism

Recombinant DNA - take a gene from one organism and place it into another organism

Transgenic or GMO - an organism that contains DNA from another organism

Would You Eat a Genetically EngineeredFood?

Would You Eat a Genetically EngineeredFood?

Most GMO’s are PlantsMost GMO’s are Plants

34% of Corn 71% of Cotton 75% of soybeans

34% of Corn 71% of Cotton 75% of soybeans

Silk is SoySilk is Soy

Why no GMOWhy no GMO

Until recently the terms Genetically Modified Organism (GMO), GMO-Free and Non-GMO were used to help identify foods that contained genetically altered ingredients.

These terms are no longer recognized by the Food and Drug Administration (FDA) and therefore cannot be used on food packaging.

Until recently the terms Genetically Modified Organism (GMO), GMO-Free and Non-GMO were used to help identify foods that contained genetically altered ingredients.

These terms are no longer recognized by the Food and Drug Administration (FDA) and therefore cannot be used on food packaging.

What about Tostito’sWhat about Tostito’s

Or Pepsi Or Coke Or CapN Crunch???

Or Pepsi Or Coke Or CapN Crunch???

How to Manipulate DNAin the Lab

How to Manipulate DNAin the Lab

Examples of TransformationExamples of Transformation Natural Systems

Bacteria Viruses

Natural Systems Bacteria Viruses

Bacterium

bacterialchromosome

plasmid

Transformation with DNA fragment

bacterialchromosome

DNAfragments

Virus enters host cell.2

virus

viral DNA

host cell

host cell DNA

“hybrid virus” viral proteins

viral DNA

Virus attaches tosusceptible host cell.1

Virus releases its DNA intohost cell; some viral DNA (red)may be incorporated into thehost cell’s DNA (blue).

3

Viral genes encode synthesisOf viral proteins and viral geneReplication. Some host cell DNAMay attach to replicated viralDNA (red/blue).

4

New viruses assemble; hostcell DNA is carried by “hybridviruses.”

5

Host cell bursts, releasingnewly assembled viruses. when “hybrid viruses” infect asecond cell, they may transfergenes from the first cell to thesecond cell.

6

GE Tool BoxGE Tool Box

Restiction Enzymes Cloning Vectors cDNA Cloning Reverse

Transcriptase PCR

Restiction Enzymes Cloning Vectors cDNA Cloning Reverse

Transcriptase PCR

Gene Library (Isolation)

Transformation of Plants

Gene Library (Isolation)

Transformation of Plants

Based on the Central Dogma and the fact that in Based on the Central Dogma and the fact that in virtually organisms the CODE is perfectly conserved virtually organisms the CODE is perfectly conserved almostalmost

Amplifying DNAAmplifying DNA

Fragments can be inserted into fast-growing microorganisms

Polymerase chain reaction (PCR)

Fragments can be inserted into fast-growing microorganisms

Polymerase chain reaction (PCR)

Polymerase Chain ReactionPolymerase Chain Reaction Sequence to be copied is heated

Primers are added and bind to ends of single strands

DNA polymerase uses free nucleotides to create complementary strands

Doubles number of copies of DNA

Sequence to be copied is heated

Primers are added and bind to ends of single strands

DNA polymerase uses free nucleotides to create complementary strands

Doubles number of copies of DNA

Polymerase Chain Reaction

Polymerase Chain Reaction

Double-stranded DNA to copy

DNA heated to 90°– 94°C

Primers added to base-pair with ends

Mixture cooled; base-pairing of primers and ends of DNA strands

DNA polymerasesassemble new DNA strands

Fig. 16-6, p. 256

Stepped Art

Polymerase Chain Reaction

Polymerase Chain Reaction

Stepped Art

Mixture heated again; makes all DNA fragments unwind

Mixture cooled; base-pairing between primers and ends of single DNA strands

DNA polymerase action again doubles number of identical DNA fragments

Fig. 16-6, p. 256

Fig. 16-7, p.247

DNA FingerprintingDNA Fingerprinting

Guilty or InnocentGuilty or Innocent

8 side-by-side (tandem) repeatsof the same 4-nucleotide sequence,

Nylon paper with DNA is bathed in a solution of labeled DNA probes (red) that are complementary to specific DNA segments in the original DNA sample.

Complementary DNA segments are labeled by probes(red bands).

nylon paper

solution of DNA probes (red)

gel

gel

power supply

DNA bands(not yet visible)

� �

wells

pipetter

nylonpaper

DNA samples are pipetted into wells(shallow slots) in the gel. Electrical currentis sent through the gel (negative at endwith wells, positive at opposite end).

Electrical current moves DNAsegments through the gel. Smallerpieces of DNA move farther toward thepositive electrode.

Gel is placed on special nylonpaper. Electrical current drivesDNA out of gel onto nylon.� �

gel

power supply

� �

wells

pipetter

DNA samples are pipetted into wells(shallow slots) in the gel. Electrical currentis sent through the gel (negative at endwith wells, positive at opposite end).

� �

DNA bands(not yet visible)

� �

Electrical current moves DNAsegments through the gel. Smallerpieces of DNA move farther toward thepositive electrode.

� �

gel� �

nylonpaper

Gel is placed on special nylonpaper. Electrical current drivesDNA out of gel onto nylon.

� �

Nylon paper with DNA is bathed in a solution of labeled DNA probes (red) that are complementary to specific DNA segments in the original DNA sample.

nylon paper

solution of DNA probes (red)� �

� �

Complementary DNA segments are labeled by probes(red bands).

� �

� �

STR name

Penta D

CSF

D16

D7

D13

D5

D16: an STR on chromosome 16

DNA samples from13 different people

Num

ber

of r

epea

ts

STR name

Penta D

CSF

D16

D7

D13

D5

Num

ber

of r

epea

ts

D16: an STR on chromosome 16

DNA samples from13 different people

Num

ber

of r

epea

ts

Genetic EngineeringTransformation of PlantsGenetic EngineeringTransformation of Plants Genes are isolated, modified, and

inserted into an organism Made possible by recombinant

technology

Cut DNA up and recombine pieces

Amplify modified pieces

Genes are isolated, modified, and inserted into an organism

Made possible by recombinant technology

Cut DNA up and recombine pieces

Amplify modified pieces

ProcessProcess

Board Diagram

Corn Transformation with RR gene

From a bacteria or petunia

Hypothetical Situation

Corn Cotton and Alfalfa

Board Diagram

Corn Transformation with RR gene

From a bacteria or petunia

Hypothetical Situation

Corn Cotton and Alfalfa

Roughly 400 million people in the world today are at risk of Vitamin A deficiency, which already affects 100-200 million children. Vitamin A deficiency causes various health problems, including blindness. Because rice is an important crop, eaten by almost half of the people in the world, the Rockefeller Foundation and the European Union funded research into varieties that might offer global health benefits.

It may now be possible, thanks to agricultural biotechnology, to make rice and other crops into additional sources of Pro-Vitamin A. With Monsanto's help, the developers of "Golden Rice" and mustard with more Pro-Vitamin A should one day be able to deliver their gift of better nutrition to the developing nations of the world through staple crops readily available to poor and vulnerable populations

Imagine sharing science to help others develop crops that could help reduce Vitamin A deficiency, a leading cause of blindness and infection among the young.

Imagine innovative agriculture that creates incredible things.

DiscussionDiscussion

Debate the Merits or Dangers of Golden Rice.

Group One - Make your case in front of Congress to obtain money to distribute this rice (as rice seed) to the farmers of Southeast Asia and Africa

Group Two - Argue against this.

Debate the Merits or Dangers of Golden Rice.

Group One - Make your case in front of Congress to obtain money to distribute this rice (as rice seed) to the farmers of Southeast Asia and Africa

Group Two - Argue against this.

You be the judgeYou be the judge

With your pocket book Or your advocacy

With your pocket book Or your advocacy

Ethical IssuesEthical Issues

Who decides what should be “corrected”

through genetic engineering?

Should animals be modified to provide

organs for human transplants?

Should humans be cloned?

Who decides what should be “corrected”

through genetic engineering?

Should animals be modified to provide

organs for human transplants?

Should humans be cloned?