1. Hypothetical Situation
Genes that produce chlorophyll in plants are inserted into the chromosomes of cattle.
What are some of the advantages of this procedure?
The result would be an animal that is capable of making its own food.
Can you think of the potential benefits of this kind of research?

2. DNA Recombination
a.k.a. Gene Splicing

3. What is it?
Recombinant DNA refers to a new combination of DNA molecules that are not found together naturally.
Produced by joining DNA molecules from different biological sources.
The hybrid DNA is then inserted into a host cell, often a bacterium, for replication.
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4. Tools Needed
Restriction enzymes (biological scissors) "cut" DNA at a specific location.
DNA ligase (DNA glue) is used to "glue" two sections of DNA together.

5. Plasmids… Recombinant DNA is often created using a plasmid.
Plasmids are DNA structures in bacteria

6. … or Viruses
The DNA in a virus can also be used for creating recombinant DNA
The virus can enter another cell and have its genetic code replicated by that cell

7. Products of Recombinant DNA Technology
Some examples of recombinant DNA products include insulin and growth hormone.
Vaccines can also be produced using recombinant DNA technology.

8. Step by Step…
Let’s look at the process of DNA recombination…

9. Step 1: A restriction enzyme is used to cut a specific DNA strand from the DNA of a cell

10. Step 2: The cut DNA strand is inserted into a virus.

11. Step 3: The virus is inserted into a cell

12. Step 4: The cell passes the foreign gene on to all daughter cells

13. A Close-up View of DNA insertion into a plasmid

14. Areas Where Recombinant DNA will have an Impact
Better Crops (drought & heat resistance)
Recombinant Vaccines (ie. Hepatitis B)
Prevention and cure of sickle cell anemia
Prevention and cure of cystic fibrosis
Production of clotting factors
Production of insulin
Plants that produce their own insecticides
Gene therapy

15. Connections to the World Around Us

16. Activity:
Make your own recombinant DNA!!

17. Impact of Recombinant DNA
Improved Medicines
Improved Livestock (resistance to disease)
Improved Crops (resistance to disease, higher yields)
Prevention of Genetic Diseases
Lowering the cost of medicines (i.e. Insulin)
Safer Medicines (i.e. Insulin)
Treatment for pre-existing conditions (i.e. Cancer)
Safety concerns (viruses developing antibiotic resistance)
Environmental concerns (developing resistance to fungi)
Ethical dilemmas over human treatment (i.e. are we playing God?)
Potential for Experimental abuse (doctors using patients as test subjects)
Germline treatment going from treating diseases to a method for picking the traits you want in a child (i.e. specifying hair and eye color)

20. Cutting DNA Strands
The major tools of recombinant DNA technology are bacterial enzymes called restriction enzymes. Each enzyme recognizes a short, specific nucleotide sequence in DNA molecules, and cuts the backbones of the molecules at that sequence. The result is a set of double-stranded DNA fragments with single-stranded ends, called "sticky ends." Sticky ends are not really sticky; however, the bases on the sticky ends form base pairs with the complementary bases on other DNA molecules. Thus, the sticky ends of DNA fragments can be used to join DNA pieces originating from different sources.
                                                       

21. Creating Recombinant Plasmids
In order to be useful, the recombinant DNA molecules have to be made to replicate and function genetically within a cell. One method for doing this is to use plasmid DNA from bacteria. Small DNA fragments can be inserted into the plasmids, which are then introduced into bacterial cells. As the bacteria reproduce, so do the recombinant plasmids. The result is a bacterial colony in which the foreign gene has been cloned.