Genetic EngineeringGenetic Engineering

II. II. Genetic engineeringGenetic engineering:: Changing an organismChanging an organism’’s s DNADNA to make it more to make it more beneficial to humansbeneficial to humans

Genetic Engineering, cont.Genetic Engineering, cont.

A.A. Recombinant DNARecombinant DNA: DNA made from : DNA made from two separate two separate speciesspecies

1.1. A gene from one organism is A gene from one organism is ““recombinedrecombined”” with another organisms with another organisms DNA.DNA.

B.B. Transgenic OrganismTransgenic Organism: any organism : any organism that contains that contains recombinantrecombinant DNA. DNA.

a.a. These new gene combinations These new gene combinations could never be possible in naturecould never be possible in nature

Researchers isolate a gene from an organism that has the trait they want to give to a plant.

and cells are grown

1.Transgenic Plants

Just for Fun?- a glowing Just for Fun?- a glowing tobacco planttobacco plant

WhatWhat’’s Next on Your s Next on Your Plate? Plate?

What genes do we want them to have?

•Insect, Herbicide, and Fungal resistance

•Drought resistance

•Product quality

•Longer Shelf Life (Flavr Savr Tomato)

http://archives.cbc.ca/IDD-1-75-1597/science_technology/genetically_modified_food/

Transgenic Organisms: Transgenic Organisms: PlantsPlants

The rice on the right is called

Golden RiceGolden Rice. Its genome contains the gene for producing vitamin A from daffodils.

This rice is healthier for people who do not get enough vitamin A in their diets.

Example:Example: Rice plants and daffodils can not Rice plants and daffodils can not cross pollinate with each other in nature.cross pollinate with each other in nature.

Transgenic Organisms: AnimalsTransgenic Organisms: Animals

Animals are now being produced with genes that increase milk production and muscle mass (meat). Problem: unhealthy; legs cannot support weight

3. Transgenic Organisms: 3. Transgenic Organisms: BacteriaBacteria

Used to produce important Used to produce important medicinesmedicines::

a.a.InsulinInsulin for diabetics for diabetics

b.b.Human growth Human growth hormone hormone (HGH) to (HGH) to treat pituitary dwarfismtreat pituitary dwarfism

c.c. Anticoagulants for (for Anticoagulants for (for treating heart attack treating heart attack patients)patients)

Bacteria cultures

Insulin

Human Genome Human Genome ProjectProject

• A A genomegenome is an is an organismorganism’’s complete set of s complete set of DNA DNA

• Project began in 1990; Project began in 1990; Completed in 2003Completed in 2003

• Coordinated by National Coordinated by National Institutes of Health (NIH) & Institutes of Health (NIH) & U.S. Department of Energy U.S. Department of Energy (DOE)(DOE)

What is the Human Genome Project What is the Human Genome Project (HGP)?(HGP)?

Goals of HGPGoals of HGP

1.1. ReadingReading and determining and determining the the sequence of the 3 billion base sequence of the 3 billion base pairs in the human genome. pairs in the human genome.

2.2. LocatingLocating and identifying and identifying all all genes in the human genome genes in the human genome which there is about 30,000 which there is about 30,000

3.3. StoringStoring information information into into databases that are accessible to databases that are accessible to the publicthe public

4. Analyzing and addressing and addressing ethical, legal, & social issues ethical, legal, & social issues involved in using this involved in using this informationinformation

Benefits of the Human Genome ProjectBenefits of the Human Genome Project

1.1. We have located many diseased We have located many diseased genesgenes and genetic tests have and genetic tests have been created.been created.

2.2. Researching bacteria genomes Researching bacteria genomes furthered research for furthered research for fuelfuel & & environmental clean-upenvironmental clean-up

3.3. Improved technology for Improved technology for DNADNA forensic scienceforensic science

4.4. Other sequences completed for Other sequences completed for E. E. coli,coli, yeast, simple round worm, yeast, simple round worm, fruit fly, rat & chimpanzeefruit fly, rat & chimpanzee (model (model organisms for studying how similar organisms for studying how similar genes work in genes work in humanshumans.).)

Maps of chromosomes # 13 & # 17; show the location of BRCA 2 & BRCA 1 – breast cancer genes.

DNA Fingerprinting/ElectrophoresisDNA Fingerprinting/Electrophoresis

DNA fingerprintingDNA fingerprinting: tool used by forensics : tool used by forensics scientists to identify a person using scientists to identify a person using DNADNA..

How it WorksHow it Works::1.1. A sample of the personA sample of the person’’s DNA is taken from blood, s DNA is taken from blood,

semen, bone, or hairsemen, bone, or hair..

2.2. DNA fragments are cut – DNA fragments are cut – RestrictionRestriction enzymes cut enzymes cut DNA at specific sequences. Useful to divide DNA DNA at specific sequences. Useful to divide DNA into manageable fragments.into manageable fragments.

ElectrophoresisElectrophoresis

3.3. DNA fragments are separated based on DNA fragments are separated based on sizesize and and chargecharge..

4.4. PhosphatePhosphate groups are negatively charged groups are negatively charged

5.5. DNA is placed into a gel & connected to an DNA is placed into a gel & connected to an electric currentelectric current

6.6. DNA moves through the gel toward + pole; DNA moves through the gel toward + pole; shortest lengths move the fastest & longest shortest lengths move the fastest & longest lengths move the slowest.lengths move the slowest.

7.7. A characteristic banding pattern is produced A characteristic banding pattern is produced and a photograph is taken and a photograph is taken

8.8. The banding pattern is The banding pattern is uniqueunique for each for each person – thus called a person – thus called a DNA fingerprintDNA fingerprint

15

ElectrophoresisElectrophoresis

16

ElectrophoresisElectrophoresis

DNA FingerprintsDNA FingerprintsWas any of the victims

blood on the defendants clothing?

Used asUsed as

evidence in evidence in

court casescourt cases

Which dog was probably the culprit (dog that bit the person)?

How Cloning Occurs in NatureHow Cloning Occurs in Nature

1.1. CloneClone: an organism that : an organism that is genetically is genetically identicalidentical to another organismto another organism

a.a. All of the genes are All of the genes are the same (identical)the same (identical)

2. 2. Examples of cloning that Examples of cloning that occurs in natureoccurs in nature

a.a. Reproduction in Reproduction in bacteria & sponges bacteria & sponges (asexual)(asexual)

b.b. Identical Identical twins are are natural clonesnatural clones

Bacteria and Plant Cloning is EasyBacteria and Plant Cloning is Easy

1.1. Cloning of transgenic Cloning of transgenic bacteriabacteria creates creates many many ““living factorieliving factoriess”” used to make used to make insulin & other & other drugsdrugs

2. 2. Cloning of transgenic Cloning of transgenic plantsplants to insure to insure genetics are intact genetics are intact for the next for the next generation.generation.

Bacteria that contain genes for digesting oil can be used to clean up oil spills.

Animal Cloning is difficult Animal Cloning is difficult and controversialand controversial

Dolly: First cloned animal

Also called Reproductive Cloning

What are Stem Cells & What are Stem Cells & Why Do Scientists Want Them?Why Do Scientists Want Them?

1.1. Stem cells: Stem cells: (link)(link) undefinedundefined cells that cells that reproduce reproduce continuously & can continuously & can develop into any type develop into any type of of cellscells or tissues or tissues

2. The hope is to be able 2. The hope is to be able to produce to produce tissuetissue & & organsorgans for for transplantstransplants

Stem cell technology can help those who wait for organ transplants.

Where do we get Stem Cells?Where do we get Stem Cells?

a)a) EmbryonicEmbryonic Stem cells Stem cells are most easily are most easily obtained from embryos and umbilical cords. obtained from embryos and umbilical cords. (work best) They are (work best) They are pluripotentpluripotent..

b)b) AdultAdult Stem cells Stem cells are found in bone marrow are found in bone marrow and skin.and skin.