1. Genetic Engineering
Genetic Engineering is the process of making changes in the DNA code of living organisms.
Genetic Engineering and DNA Technology can be used to
Cure diseases
Treat genetic disorders
Improve food crops
Produce vaccines and
other useful drugs

2. Genetic Engineering Includes
Selective Breeding & Crossbreeding
Recombinant DNA
Transgenic Organisms
PCR
DNA Fingerprinting
Gel Electrophoresis
Cloning

3. Selective Breeding
Breed only those plants or animals with desirable traits
People have been using selective breeding for 1000’s of years with farm crops and domesticated animals.

4. Hybridization (Crossbreeding)
Producing new organisms by the mating individuals of different breeds, varieties, or species
Male Donkey + Female Horse = Mule

5. Recombinant DNA rDNA has been artificially created
DNA from two or more sources is recombined into a single molecule
To create rDNA, scientists use restriction enzymes to cut DNA in precise locations
Restriction enzymes create “sticky ends” that allow the DNA to bind to another piece of DNA with the same sticky ends

6. Recombinant Bacteria Remove a Plasmid
A plasmid is a small circular piece of DNA found in bacteria
Cut the Bacterial DNA with restriction enzymes
Cut the desired gene from another organism’s DNA with restriction enzymes
Combine the cut pieces of DNA together and insert them into bacteria.
Reproduce the recombinant bacteria.
The foreign genes will be expressed in the bacteria.

7. Recombinant Bacteria

8. Benefits of Recombinant Bacteria
Bacteria can make human insulin or human growth hormone.
Bacteria can be engineered to “eat” oil spills.

9. Transgenic Organisms
The genetic code is universal, therefore it is possible to make organisms that are transgenic
Transgenic organisms contain genes from other species
They are also called GMO’s – Genetically Modified Organisms
This tobacco plant glows in the dark because scientists gave it the gene that causes fireflies to glow

10. Transgenic Plants Disease-resistant and insect-resistant crops
Hardier fruit
70-75% of food in supermarket is genetically modified.

11. Transgenic Animals Mice – used to study human immune system
Chickens – more resistant to infections
Cows – increase milk supply and leaner meat
Goats, sheep and pigs – produce human proteins in their milk

12. Polymerase Chain Reaction PCR
PCR is a fast and inexpensive technique used to amplify (copy) small amounts 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.

13. DNA Fingerprinting
A technique used by scientists to distinguish between individuals of the same species using only samples of their DNA
Unless they are identical twins, individual organisms all have unique DNA.
The chemical structure of the DNA may be the same (A, T, C & G), but the order of the base pairs is different

14. DNA Fingerprinting Process
First, DNA must be obained from blood, bodily fluids, hair roots, skin, or elsewhere
After the DNA is isolated, it is amplified using PCR
Then the DNA is treated with restriction enzymes
Cut the DNA at specific sequences
This results in different sized fragments
These fragments are separated, based on size, using a process called Gel Electrophoresis

15. Gel Electrophoresis
DNA fragments are separated as they migrate through an agarose gel matrix
This size-based separation occurs when an electric current is applied to the gel

16. Gel Electrophoresis
DNA is a negatively charged molecule, so it will move toward the positive end of the chamber
The smaller fragments will move faster and farther than the larger fragments

17. Gel Electrophoresis Steps
1. “Cut” DNA sample with restriction enzymes.
2. Run the DNA fragments through a gel.
3. Bands will form in the gel.
4. Everyone’s DNA bands are unique and can be used to identify a person.

19. DNA Fingerprinting
DNA fingerprinting can show which individuals are the parents of specific children
A child’s DNA fragments must be inherited from his or her biological parents

20. DNA Fingerprinting
DNA fingerprinting can also be used to help solve crimes

21. Cloning
Cloning is the creation of an organism that is an exact genetic copy of another
Their DNA is identical
Produced by asexual reproduction
Mitosis

22. Cloning
Dolly the sheep was the first animal to be successfully cloned in 1997
There were failures before this nuclear transfer technique succeeded