1. Changing the Living World & Manipulating DNA

2. Selective Breeding
Uses naturally occurring genetic variation in plants, animals, and other organisms
Breed specific individuals
Pass on desired traits
Naturally occurring genetic variation
Desired traits

3. Selective Breeding

4. Hybridization
Crossing different species to bring together the best of both organisms.
Hybrids are often hardier than either of the parents. Why might this be?
Different species to

5. Genetic Engineering Altering the genetic code of an organism.
How do we do this?
1. DNA extraction
2. Cut the DNA
3. Separate out genes
Genetic code
What are the tools of molecular biology?
DNA extraction
Cutting the DNA
Separating out genes
Cut and paste segments of DNA – recombinant DNA is formed

6. Genetic Engineering How do we change a DNA sequence?
Cut and paste segments of DNA
Recombinant DNA is formed
Genetic code
What are the tools of molecular biology?
DNA extraction
Cutting the DNA
Separating out genes
Cut and paste segments of DNA – recombinant DNA is formed

7. Genetic Engineering
How do we get the recombinant DNA back into a living cell?
Bacteria can be transformed using recombinant DNA.
New DNA is joined with the plasmid of the bacteria cell.
Plasmid = small circular DNA
Transformation
transformed
Plasmid
Small, circular DNA molecule

8. Transformation

9. Transformation We use this process to: Insert desired genes/traits
When organisms contain genes from another species, they are called:
Transgenic organisms or genetically modified organisms
Insert desired genes/traits
Transgenic organisms or genetically modified organisms

11. Transgenic Organisms
This is what we mean when we say a plant (like the ones we might eat or buy) has been genetically engineering or modified (GMOs)

12. Transgenic Organisms

13. Cloning
A clone is a genetically identical cell produced from a single cell.
Cloned colonies of bacteria are simple to grow….but more complex organisms are a much bigger challenge!
First complex species cloned:
In Wilmut cloned a sheep named Dolly…
Genetically identical cell produced from a single cell.
In 1997, Wilmut cloned a sheep named Dolly…

14. Cloning Dolly… Potential application of cloning:
Saving endangered species
Making copies of transgenic organisms

15. Gene Therapy
An absent or faulty gene is replaced by a normal, working gene
Viruses are often used because they have the ability to enter a cell’s DNA.
Gene … normal, working gene

16. Gene Therapy How does this work?
1. The virus is modified so that it cannot cause disease.
2. A DNA fragment with the replacement gene is spliced to the viral DNA.
3. The patient is infected with the modified viruses
How Does This Work?
The virus is modified so that it cannot cause disease.
A DNA fragment with the replacement gene is spliced to the viral DNA.
The patient is infected with the modified viruses

18. Gene Therapy-Considerations
Unfortunately, these experiments have not been very successful.
Gene therapy remains a high-risk, experimental procedure.
Ethical considerations??