1. Biotechnology Guess the lamb’s name
DOLLY!--THIS IS A PHOTO OF THE FAMOUS CLONED SHEEP

2. Goals of Applied Genetics
Help humans create crops that can be frost resistant
Use transgenic organisms to help medical researchers model human physiology for testing
Help industry to create bacteria to break down pollutants into harmless products
Pharmaceutical companies use recombinant DNA to cheaply produce human hormones (insulin) and other proteins
Help solve crimes and determine familial relationships

3. Selective breeding Selecting organisms with the most desirable traits
Requires time and several generations to produce offspring with the desired trait
Ex:
Short vs long haired cats
Milk production in cattle
Disease resistant foods
Bacteria that break down oil

4. Genetic Engineering
Also called, recombinant DNA technology or gene cloning
Uses a bacterial host because of fast reproduction and a circular DNA vehicle to hold the foreign DNA=plasmid
Organisms containing recombinant DNA or foreign DNA are known as transgenic

5. Steps involved:
select the desired gene(s) to be inserted into the organism and a bacterial host containing a plasmid (vehicle to hold the desired gene)
cut specific DNA molecules into fragments with special (restriction) enzymes
splice (rejoin) the fragments (gene and plasmid) together in the desired combination
introduce or insert the new DNA into a living cell for replication (mitosis)

6. = Vector to transfer DNA

7. Restriction Enzymes
Used to cut a DNA molecule at a specific nucleotide sequence
Produces one of two types of DNA fragments
Sticky ends (palindrome)
Blunt ends

8. Sticky Ends
(palindrome)
Blunt ends

10. = Vector to transfer DNA

11. Vectors
Vector: in nature, an organism that can transmit DNA to another organism, often an infection
Biotechnology uses this ability to transfer desired genetic information to a host cell.

12. Gene Libraries Store DNA sequences for biotech applications
May use plasmid or phage
(Phage: virus that infects bacteria and looks like a spaceship)
May contain entire genome or only DNA used in gene expression.
Expressed DNA is called cDNA (complementary DNA) and is made from mRNA with the enzyme...

13. Reverse Transcriptase!!!!

14. Gene Cloning
Used to produce genetically identical copies of a cell, tissue, organ, and/or organism
Needed to produce multiple copies of the desired DNA

15. Cloning Applications Currently
Plants are cloned to produce a large number of genetically identical plants in a short amount of time
Future?
Clone productive and healthy animals to increase yield for farmers and to grow organs for transplants

16. How it works….

17. Gene Therapy
The insertion of normal genes into human cells to correct genetic disorders like cystic fibrosis.

18. DNA Fingerprinting Obtain a small sample of DNA
Make millions of copies using PCR (polymerase chain reaction) technique
Cleave (cut) DNA with restriction enzymes
Separate DNA fragments using gel electrophoresis and compare
Each human’s DNA will have some unique pieces because each of our DNA is unique

19. Restriction Fragment Length Polymorphism (RFLP)
RFLP: Each individual..
...has different numbers of restriction sites
...different # of base pairs between restriction sites
Gel electrophoresis is used to create a DNA fingerprint of these unique sizes.
Small amounts of DNA are loaded into wells in the gel.
An electric current pushes the small pieces of DNA farther down the gel than the larger pieces.

20. RFLP DNA patterns are compared to known patterns.
Used for forensics, blood samples, and paternity tests (children get half their bands from mom and half from dad)

21. Running a gel…

22. How DNA moves… Step 1: Pour gel with comb for wells,
not unlike a jello
mold.

23. Step 2:
Pipette DNA into wells.
DNA has been cut with
restriction enzymes.

24. Step 3:
Run an electric current
to watch
DNA
migrate.
Small strands,
fewer base pairs, travel further.

25. Step 4:
Notice similarities
and differences
in banding
patterns.

27. The Human Genome Project
There are approximately 80,000 genes on the 46 human chromosomes
Human Genome Project- an international effort to completely map and sequence human chromosomes (April 2003)

28. Southern Blotting
Purpose: to use a cloned gene to probe for the same gene in another sample.
Named for Edward M. Southern-
Western and Northern Blots play on that name
These have slightly different procedure (Western involves protein rather than DNA)

29. Southern Blotting Unknown DNA is run on a gel.
DNA bands are blotted onto special paper.
Paper is flooded with labeled complementary DNA
p32

30. Southern Blotting
Hybridization: Single stranded DNA probe binds to any complementary DNA on paper, and the rest is washed off
Bands that are hybridized are radioactive and can be visualized.

31. Uses of Radioactive Probes
Biochemists use radioactive probes to find things such as:
Genes
Proteins
Enzymes
Receptors on membranes
Antigens (by using radioactive antibodies)

32. Bioinformatics
This area of study uses genetic material (or any biological material) to gather information.
Such as…

33. Bioinformatics
Whether a gene is similar to a previously sequenced gene.
Whether a specific gene is correlated with a specific disease, such as which genes are prevalent in cancer cells.
Whether a certain drug can benefit or harm a patient based on the patient’s genotype.

34. Credits
This Power Point was provided by Abby Price and modified by Andrea Wise, Providence High School, 2007